Secret Papers

Question 1

• According to Okada, et al. (JAVMA, 2010), what is a characteristic feature of myelomalacia on T2w images?
  
  • Also, what changes were noted in CSF?
• A different study by Gilmour, et al. (VRU, 2015), found what factor(s) to be predictive of myelomalacia using T2w images and SSTSE sequences?

Answer 1

• Okada: T2w-hyperintensity > 6x the length of L2
  
  • Xanthochromia
• Gilmour:
  
  • CSF:L2_SSTSE < 7.4 – unlikely to develop myelomalacia
  • CSF:L2_SSTSE > 12.5 – suggested cut-off to minimize number of false positives (100% specific)

Okada, M., Kitagawa, M. & Ito, D. (2010) Magnetic resonance imaging features and clinical signs associated with presumptive and confirmed progressive myelomalacia in dogs: 12 cases (1997–2008). Journal of the American Veterinary Medical Association 237, 1160–1165

Gilmour, L.J., Jeffery, N.D., Miles, K., et al. (2017) SINGLE-SHOT TURBO SPIN ECHO PULSE SEQUENCE FINDINGS IN DOGS WITH AND WITHOUT PROGRESSIVE MYELOMALACIA. Veterinary Radiology & Ultrasound 58, 197–205

Question 2

Name the labeled structures and determine the anomaly.

Answer 2

1. CVC
2. Ao
3. PV

Intrahepatic PSS

Bruehschwein, A., Foltin, I., Flatz, K., et al. (2010) Contrast-enhanced magnetic resonance angiography for diagnosis of portosystemic shunts in 10 dogs. Veterinary Radiology and Ultrasound 51, 116–121

Question 3

• What is the most frequent location for a gastric leiomyoma/sarcoma?
• Although there is a great deal of overlap, and there are no specific differentiating characteristics, what are some features of intestinal neoplasia can help to differentiate inflammatory disease from neoplasia?
• (T/F) Intestinal carcinoma is most often solitary but is also commonly multifocal.
• What CT features can help distinguish gastric lymphoma from other types of neoplasia?

Answer 3

• What is the most frequent location for a gastric leiomyoma/sarcoma? Pylorus
• Although there is a great deal of overlap, and there are no specific differentiating characteristics, what are some features of intestinal neoplasia can help to differentiate inflammatory disease from neoplasia?
  
  • Neoplastic infiltration has a median wall thickness statistically greater than inflammatory disease (15mm vs. 6mm)
  • Loss of wall layering
• Intestinal carcinoma is most often solitary.
• What CT features can help distinguish gastric lymphoma from other types of neoplasia?
  
  • Lower mean attenuation on both early and delayed post-contrast phases
  • More widespread lymphadenopathy with larger lymph nodes

Simeoni, F., Signore, F. Del, Terragni, R., et al. (2020) Diagnostic Imaging of Gastrointestinal Tumours in Dogs and Cats : A Review. American Journal of Animal and Veterinary Sciences 15, 89–101

Question 4

More GB sludge:

• Serial US over the course of a year showed what changes to GB sludge?

Answer 4

• No significant difference in median amount of sludge
• Most dogs remained asymptomatic
• Some dogs had more sludge and some had sludge that became non-dependent

DeMonaco, S.M., Grant, D.C., Larson, M.M., et al. (2016) Spontaneous Course of Biliary Sludge Over 12 Months in Dogs with Ultrasonographically Identified Biliary Sludge. Journal of Veterinary Internal Medicine 30, 771–778

Question 5

Regarding radiographic changes associated with mycobacterium infection in cats (Bennett, 2011 JFMS):

• What were the most common changes in the thorax?
• Abdomen?
• Appendicular skeleton?
• What are some of the less common findings described in this report?

Answer 5

• Thorax:
  
  • Commonly mixed bronchial, alveolar, and nodular interstitial patterns
  • Perihilar and sternal lymphadenopathy
• Abdomen:
  
  • Uncommon, but include hepatosplenomegaly
• Skeletal:
  
  • Permeative osteolysis, periosteal reaction, soft tissue swelling
• Less common findings:
  
  • Mineralization of the great vessels
  • Dystrophic soft tissue mineralization
  • Submandibular soft tissue swelling

Bennett, A.D., Lalor, S., Schwarz, T., et al. (2011) Radiographic Findings in Cats with Mycobacterial Infections. Journal of Feline Medicine & Surgery 13, 718–724

Question 6

Likely diagnosis?

Answer 6

Gastroesophageal intussusception

Pollard, R.E. (2012) Imaging Evaluation of Dogs and Cats with Dysphagia. ISRN Veterinary Science 2012, 1–15

Question 7

Regarding the sonographic features of thymomas and mediastinal lymphoma:

• What are the typical sonographic characteristics of each tumor?
• Which features were significant differentiators?

Answer 7

• Lymphoma:
  
  • About 50/50 hypoechoic vs. heterogeneously echogenic
  • Mostly solid and commonly lobulated
• Thymoma:
  
  • Almost all were heterogeneously echogenic
  • 60% cystic
  • Mostly lobulated shape with irregular/indistinct margins
• Which features were significant differentiators?
  
  • Heterogeneity and cysts (NS) more suggestive of thymoma

Patterson, M.M.E. & Marolf, A.J. (2014) Sonographic characteristics of thymoma compared with mediastinal lymphoma. Journal of the American Animal Hospital Association 50, 409–413

Question 8

Describe the normal progression (phases) of a excretory urogram

Answer 8

• Arterial phase: arterial renal blood flow, is extremely brief, and usually has already passed when the first image is made
• Nephrogram phase: contrast accumulation in the renal tubules
• Pyelogram phase: contrast accumulation in the collecting system (diverticuli, pelvis, ureters)
• Cystogram: contrast accumulation in the bladder

Pugh, C.R., Rhodes, W.H. & Biery, D.N. (1993) Contrast Studies of the Urogenital System. Veterinary Clinics of NA: Small Animal Practice 23, 281–306

Question 10

Regarding MRI of vertebral endplate changes in dogs (Gendron, VRU 2012):

• What were the imaging characteristics of the following categories of endplate changes?
  
  • Reactive changes
  • Fatty infiltration
  • Sclerosis
  • Osteochondrosis
  • Schmorl’s node
• What other category of endplate changes were evaluated?

Answer 10

• Reactive changes: T2w/STIR hyperintense, T1w-hypointense, +/- CE
• Fatty infiltration: T1 & T2w-hyperintensities nulled on STIR
• Sclerosis: T2/T1w-hypointense
• Osteochondrosis: defect on dorsal edge of endplate +/- fragment, material filling the gap is isointense to disc
• Schmorl’s node: centrally-located, well-marginated, focal endplate defect contiguous with disc and filled with disc-isointense material
• Also looked at disko

GENDRON, K., DOHERR, M.G., Gavin, P., et al. (2012) MAGNETIC RESONANCE IMAGING CHARACTERIZATION OF VERTEBRAL ENDPLATE CHANGES IN THE DOG. Veterinary Radiology & Ultrasound 53, 50–56

Question 11

Regarding MRI of dogs with head trauma:

• What features were linked to prognosis?
• How did the patterns of injury in dogs compare to those in humans?

Answer 11

• Prognosis:
  
  • Injuries affecting the caudal fossa or causing a severe midline shft were associated with increased mortality
  • Herniation through an open fontanelle was somehow associated with a good outcome
• Different patterns of intracranial trauma in dogs than humans

Yanai, H., Tapia-Nieto, R. & Cherubini, G.B. (2015) Results of magnetic resonance imaging performed within 48 hours after head trauma in dogs and association with outcome: 18 cases (2007–2012). Journal of the American Veterinary Medical Association 246, 1222–1229

Question 12

Some normal measurements of the horse LUT:

• Bladder wall
• Ureteral wall
• Urethral wall

Answer 12

• Bladder wall: 3mm
• Ureteral wall: 1.8 mm
• Urethral wall: 5mm

Question 13

• What is the most common distribution of thyoid disease in cats (i.e., bilateral/unilateral)?
• How common is ectopic thyroidal tissue in cats?

Answer 13

• What is the most common distribution of thyoid disease in cats (i.e., bilateral/unilateral)? IN ORDER
  
  • Bilateral asymmetric
  • Unilateral
  • Bilateral symmetric
  • Multifocal
• How common is ectopic thyroidal tissue in cats?
  
  • Uncommon – about 4% of cats

Peterson, M.E. & Broome, M.R. (2015) Thyroid scintigraphy findings in 2096 cats with hyperthyroidism. Veterinary Radiology and Ultrasound 56, 84–95

Question 14

Positive contrast MRI bursography for assessement of the structures of the foot:

• What dose of saline/contrast solution achieved distension of the navicular bursa such all structures of interest were separated from one another?
• (T/F): Structures of the distal aspect of the navicular bursa distend with lower volumes of solution and structures of the proximal aspect require larger volumes.
• What abnormalities can be identified using this procedure?

Answer 14

• What dose of saline/contrast solution achieved distension of the navicular bursa such all structures of interest were separated from one another? 6 ml
• (F): Structures of the distal aspect of the navicular bursa distend with lower volumes of solution and structures of the proximal aspect require larger volumes.
  
  • Opposite – proximal filled first
• What abnormalities can be identified using this procedure?
  
  • Can rule out adhesions if structures separate with distension
  • Can increase index of suspicion for adhesions if they fail to separate
  • Flexor erosions previously obscured due to close proximity of DDFT

MAHER, M.C., Werpy, N.M., Goodrich, L.R., et al. (2011) POSITIVE CONTRAST MAGNETIC RESONANCE BURSOGRAPHY FOR ASSESSMENT OF THE NAVICULAR BURSA AND SURROUNDING SOFT TISSUES. Veterinary Radiology & Ultrasound 52, 385–393

Question 15

What is the normal appearance of horse urine on US?

Answer 15

Swirling, echogenic. Likely due to mucus and calcium carbonate.

doi: 10.1111/j.1740-8261.2007.00297.x

Question 16

• What are differentials for this image of a 12yr Thoroughbred gelding?
• Given the ultimate diagnosis, what was the prognosis?
• What treatment was initiated?

Answer 16

• DDX:
  
  • Fungal pneumonia
  • Interstitial pneumonia
    
    • Equine multinodular pulmonary fibrosis; associated with EHV-5
  • Pulmonary neoplasia
• Given the ultimate diagnosis, what was the prognosis?
  
  • Fair to poor
    
    • 3/5 euthanized due to failure to improve/deterioration
    • 2/5 responded favorably to treatment
• What treatment was initiated?
  
  • Corticosteroids
  • Anti-virals
  • Sildenafil and lasix in a horse with PHT

Wong, D.M., Belgrave, R.L., Williams, K.J., et al. (2008) Multinodular pulmonary fibrosis in five horses. Journal of the American Veterinary Medical Association 232, 898–905

Question 17

Regarding the appearance of muscular metastasis on CT:

• What was the typical appearance of muscular metastatic lesions?
• Where were they most commonly located?
• What was different about metastatic lesions in the myocardium?

Answer 17

• What was the typical appearance of muscular metastatic lesions?
  
  • Well-defined, oval to round, isodense pre- and contrast-enhancing post C+ (homogeneous/heterogeneous/ring)
• Where were they most commonly located?
  
  • Epaxial/paraspinal muscles > thoracic wall > scapula/shoulder = hind limb > abdominal wall
• What was different about metastatic lesions in the myocardium?
  
  • Isodense pre-C, hypodense post-C

Vignoli, M., Terragni, R., Rossi, F., et al. (2013) WHOLE BODY COMPUTED TOMOGRAPHIC CHARACTERISTICS OF SKELETAL AND CARDIAC MUSCULAR METASTATIC NEOPLASIA IN DOGS AND CATS. Veterinary Radiology & Ultrasound 54, 223–230

Question 18

Regarding the CT features of lipomatous masses in dogs:

• What features differentiate lipomas from infiltrative lipomas?
• What features differentiate liposarcomas?

Answer 18

• Lipoma: round or ovoid, well-marginated, fat attenuating, non-CE
• Infiltrative lipoma: homogeneous, fat-attenuating, non-CE but with irregular shape and linear hyperattenuating components
• Liposarcomas: heterogeneous, primarily soft-tissue attenuating with some foci of fat, CE, nodular masses +/- mineralization or regional lymphadenopathy

Tumor definition and shape were most useful for differentiating lipoma vs. infiltrative lipoma

Soft tissue, heterogeneous mass with mineralization and regional lymphadenopathy was useful for liposarcoma

Spoldi, E., Schwarz, T., Sabattini, S., et al. (2017) Comparisons Among Computed Tomographic Features of Adipose Masses in Dogs and Cats. Veterinary Radiology and Ultrasound 58, 29–37

Question 19

• What are the MRI features of septic arthritis in horses?
• What are the MRI features of septic and non-septic arthritis in foals?
• What are the “rim sign” and “penumbra sign” in this context?

Answer 19

• Horses and foals with septic arthritis:
  
  • Diffuse hyperintensity in bone and extracapsular tissues on FS images – foals also had hypointense halo
  • Joint effusion – fluid is less T2 hyperintense than normal synovial fluid
  • Synovial proliferation – low T2w-signal, (+) CE
  • Capsular thickening
  • Foals have subchondral hemorrhage
• Non-infectious foals:
  
  • Joint effusion
  • No bone lesions, no synovial thickening
• Osteomyelitis has characteristic rim sign (hypointense halo surrounding active disease) and penumbra sign (zone of transition of increasing signal intensity and the surrounding sclerotic bone on T1 images)

EASLEY, J.T., BROKKEN, M.T., Zubrod, C.J., et al. (2011) MAGNETIC RESONANCE IMAGING FINDINGS IN HORSES WITH SEPTIC ARTHRITIS. Veterinary Radiology & Ultrasound 52, 402–408

GASCHEN, L., LEROUX, A., TRICHEL, J., et al. (2011) MAGNETIC RESONANCE IMAGING IN FOALS WITH INFECTIOUS ARTHRITIS. Veterinary Radiology & Ultrasound 52, 627–633

Question 20

• What are the CT findings associated with laryngeal collapse?
  
  • What concomitant abnormalities were noted in these dogs?
• What are the CT findings associated with laryngeal paralysis?

Answer 20

• What are the CT findings associated with laryngeal collapse? What concomitant abnormalities were noted in these dogs?
  
  • MUST be assessed with 3D internal volume rendering
  • Everted laryngeal saccules
  • Medial +/- ventral collapse of cuneiform processes
  • All dogs with LC were brachycephalic
  • Concomitant abnormalities:
    
    • Bronchial collapse
    • Elongated soft palate (extending past epiglottis)
    • Tracheal hypoplasia +/- collapse
• Laryngeal paralysis
  
  • Failure to abduct arytenoids
  • Collapse of rima glottis
  • Stenosis of laryngeal inlet
  • Air in ventricles

Stadler, K.L., HARTMAN, S., MATHESON, J., et al. (2011) COMPUTED TOMOGRAPHIC IMAGING OF DOGS WITH PRIMARY LARYNGEAL OR TRACHEAL AIRWAY OBSTRUCTION. Veterinary Radiology & Ultrasound 52, 377–384

Question 21

Zwingenberger, A.L., Marks, S.L., Baker, T.W., et al. (2010) Ultrasonographic Evaluation of the Muscularis Propria in Cats with Diffuse Small Intestinal Lymphoma or Inflammatory Bowel Disease. Journal of Veterinary Internal Medicine 24, 289–292

This paper had discordant results about the sonographic appearance of IBD and LSA in comparison to other studies. What was the significant difference in this patient population?

Answer 21

IBD was not associated with muscularis thickening.

Question 22

Regarding incomplete longitudinal fractures of the proximopalmar aspect of MCIII in horses:

• What was the most common orientation and location for a stress-related injury? What forms did these injuries take?
• What was the correlation of these findings with scintigraphy?

Answer 22

• What was the most common orientation and location for a stress-related injury? What forms did these injuries take?
  
  • Incomplete fracture and/or increased opacity in a proximodistal orientation, more often medial
• What was the correlation of these findings with scintigraphy?
  
  • In 50% with IRU, there were rad abnormalities and in 50% there were no rad abnormalities.
  • Majority of horses with a fracture line had moderate to marked IRU, however this was not significant.

Morgan, R. & Dyson, S. (2012) Incomplete longitudinal fractures and fatigue injury of the proximopalmar medial aspect of the third metacarpal bone in 55 horses. Equine Veterinary Journal 44, 64–70

Question 23

Regarding aortic lesions in dogs with spirocercosis:

• What are the common CT features?
• What was the average length of CT lesions of the aorta?
• How well did radiography predict the lesions identified on CT?
• What CT feature was significantly associated with neoplastic transformation of esophageal nodules?
• T/F: dogs with spirocercosis tend to be hypocoagulable

Answer 23

• What are the common CT features?
  
  • Aortic mineralization
  • Aortic aneurysm
  • Aortic thrombi
• What was the average length of CT lesions of the aorta? 4 vertebral bodies
• Radiography overdiagnosed aneurysms but underdiagnosed mineralization
• What CT feature was significantly associated with neoplastic transformation of esophageal nodules? Mineralization
• HYPERcoagulable

Kirberger, R.M., Stander, N., Cassel, N., et al. (2013) Computed tomographic and radiographic characteristics of aortic lesions in 42 dogs with spirocercosis. Veterinary Radiology and Ultrasound 54, 212–222

Question 24

• What is the likely diagnosis in this patient given the abnormality indicated by the black arrow?

Answer 24

• Laryngeal paralysis – air-filled ventricles
• Laryngeal collapse – no gas in ventricles, increased soft tissue opacity of larynx

Stadler, K.L., HARTMAN, S., MATHESON, J., et al. (2011) COMPUTED TOMOGRAPHIC IMAGING OF DOGS WITH PRIMARY LARYNGEAL OR TRACHEAL AIRWAY OBSTRUCTION. Veterinary Radiology & Ultrasound 52, 377–384

Question 25

• How do different anesthetic protocols affect uptake of ¹⁸FDG by the brain in PET/CT imaging?
• What is the mechanism by which certain protocols will result in higher OR lower SUV?

Answer 25

• Standard uptake value (SUV) for the frontal and occipital lobes was significantly higher than in the cerebellum and brainstem in all dogs regardless of protocol
• Dogs receiving medetomidine/pentobarbital and medetomidine/tiletamine-zolazepam
  
  • Occipital > temporal, cerebellum
  • Also had significantly higher whole brain SUVs than the propofol/isoflurane group
• Propofol and iso are known to depress glucose metabolism
• Medetomidine suppresses insulin release –> hyperglycemia

LEE, M.I.N.S.U., KO, J., LEE, A.H.R.A., et al. (2010) EFFECTS OF ANESTHETIC PROTOCOL ON NORMAL CANINE BRAIN UPTAKE OF 18F-FDG ASSESSED BY PET/CT. Veterinary Radiology & Ultrasound 51, 130–135

Question 26

According to a very old study that probably shouldn’t be referenced anymore…

• Which view was most sensitive for the detection of pulmonary metastatic disease?
• Which was least sensitive?
• What was the least sensitive combination of two views?

Answer 26

• Which view was most sensitive for the detection of pulmonary metastatic disease? RLV
• Which was least sensitive? VDV
• What was the least sensitive combination of two views? LLV + VDV

Lang, J., Wortman, J.A., Glickman, L.T., et al. (1986) SENSITIVITY OF RADIOGRAPHIC DETECTION OF LUNG METASTASES IN THE DOG. Veterinary Radiology & Ultrasound 1–5

Question 27

In a study of 13 dogs with discospondylitis, what was an uncommon finding in terms of vertebral signal intensity and what is the proposed explanation for this finding?

Answer 27

• Low incidence of T2w-hyperintensity of the vertebral body (11%)
• This was found in the dogs with a more acute history of spinal pain and ataxia
  
  • Almost all of the rest of the dogs in this study had clinical signs for >3 weeks
• This likely reflects acute/recent infection

Carrera, I., Sullivan, M., MCCONNELL, F., et al. (2011) MAGNETIC RESONANCE IMAGING FEATURES OF DISCOSPONDYLITIS IN DOGS. Veterinary Radiology & Ultrasound 52, 125–131

Question 28

• Using the right lateral view, what is the mean ratio of kidney length to the second lumbar vertebra length for different skull types?
• In addition to skull type, what signalment characteristics were statistically significant?

Answer 28

• Ratios based on skull type
  
  • Brachycephalic dogs: 3.1
  • Dolichocephalic dogs: 2.8
  • Mesaticephalic dogs: 2.97
• Smaller dogs had larger ratios
• NO significant difference based on age or sex

Lobacz, M.A., Sullivan, M., Mellor, D., et al. (2012) EFFECT OF BREED, AGE, WEIGHT AND GENDER ON RADIOGRAPHIC RENAL SIZE IN THE DOG. Veterinary Radiology & Ultrasound 53, 437–441

Question 29

Regarding CNS Coccidioides infection in dogs and cats:

• Location?
• Signal characteristics and CE?
• Ancillary changes?
• Major differentials based on MRI appearance?
• For bonus points, describe the atypical appearance of coccidiomycosis that was more recently described by Spoor et. al. (VRU, 2019)

Answer 29

• Solitary mass lesion that could be intra- or extra-axial, and often difficult to definitively determine. Intra-cranial or spinal.
• Primarily T2w hyperintense, T1w iso- to hypointense (but also could be anything)
• Primarily marked CE with a few that had minimal or no CE
• Indistinct margins, mass effect, extensive peri-lesional edema
  
  • 2/11 had a dural tail sign
• Main differentials: meningioma and glioma
• Novel form: bilaterally symmetric T2w-hyperintensity throughout the frontal lobes, caudate nuclei, internal capsule +/- wispy CE. Severe atrophy of affected regions on recheck MRI

Bentley, R.T., Heng, H.G., Thompson, C., et al. (2015) MAGNETIC RESONANCE IMAGING FEATURES AND OUTCOME FOR SOLITARY CENTRAL NERVOUS SYSTEM COCCIDIOIDESGRANULOMAS IN 11 DOGS AND CATS. Veterinary Radiology & Ultrasound 56, 520–530

Spoor, E., Stainback, L., Plummer, S., et al. (2019) A novel form of intracranial coccidioidomycosis is present in dogs and exhibits characteristic clinical and magnetic resonance imaging findings. Veterinary Radiology and Ultrasound 60, 47–55

Question 30

What are the characteristics of cricopharyngeal dyssynchrony as measured on videofluoroscopic exam?

Answer 30

• Delayed time to UES opening (0.3) and closing (0.6)
• Time to max pharyngeal contraction and epiglottic reopening are normal

Pollard, E. & Marks, L. (1999) Quantitative Videofluoroscopic Evaluation of Pharyngeal.

Question 31

What is the normal pharyngeal constriction ratio in the dog? How is it calculated?

Answer 31

0.15 +/- 0.3 PCR = #pixels in max constriction frame / #pixels in hold frame

Question 32

What are the four types of osteopetrosis?

Answer 32

1. Precocious form: reported in Angus calves, quickly fatal
2. Intermediate form: milder signs, begins early in life
   
   • Anemia, hepatomegaly, fractures short stature
3. Osteopetrosis with renal tubular acidosis and cerebral calcifications
   
   • Not reported in animals
4. Delayed type
   
   • May be asymptomatic or may leaf to fractures, bone pain, cranial nerve palsies

Hanel, R.M., Graham, J.P., Levy, J.K., et al. (2004) Generalized Osteosclerosis in a Cat. Veterinary Radiology & Ultrasound 45, 318–324

Question 33

CEUS of the small bowel in healthy cats:

• Arrival time
• Time to peak (from injection)

Answer 33

Arrival time: 7 sec

TTP: 10 sec

Diana, A., Specchi, S., Baron Toaldo, M., et al. (2011) CONTRAST-ENHANCED ULTRASONOGRAPHY OF THE SMALL BOWEL IN HEALTHY CATS. Veterinary Radiology & Ultrasound 52, 555–559

Question 34

Clumping of the suspended echoes in cat bladder is associated with increased concentration of what compound?

Answer 34

Diacylglycerol – very hydrophobic

doi: 10.1111/vru.12100

Question 35

• (T/F): Dogs with chronic PVT are more likely to survive than dogs with acute PVT
• (T/F): Multiple sites of thrombosis in addition to the PVT is associated with non-survival
• (T/F): Medical management with antithrombotics and anticoagulants has no significant impact on outcome
• Which of the following are significantly associated with survival or non-survival?
  
  • Glucocorticoid therapy
  • Neoplasia
  • Multiple thrombi
  • Severe ascites
  • >1 thrombotic risk factors
  • SVT
  • SIRS

Answer 35

• (T): Dogs with chronic PVT are more likely to survive than dogs with acute PVT
• (T): Multiple sites of thrombosis in addition to the PVT is associated with non-survival
• (F): Medical management with antithrombotics and anticoagulants has no significant impact on outcome
  
  • Positively associated with survival
• Which of the following are significantly associated with survival or non-survival?
  
  • Glucocorticoid therapy
  • Neoplasia
  • Multiple thrombi – nonsurvival
  • Severe ascites
  • >1 thrombotic risk factors
  • SVT
  • SIRS – nonsurvival

Respess, M., O’Toole, T.E., Taeymans, O., et al. (2012) Portal Vein Thrombosis in 33 Dogs: 1998-2011. Journal of Veterinary Internal Medicine 26, 230–237

Question 36

Contrast reactions:

• What are the common types of reactions noted with administration of iodinated and Gd-based contrast agents?
  
  • Dogs
  • Cats

Answer 36

• Changes to vital parameters increased or decreased in different animals; the predominant changes are listed below:
  
  • Iodinated:
    
    • Dogs: decreased HR, increased RR
    • Cats: decreased HR, RR, MAP
  • Gd-based:
    
    • Dogs: increased HR, RR, MAP
    • Cats: increased HR, RR, MAP

Scarabelli, S., Cripps, P., Rioja, E., et al. (2016) Adverse reactions following administration of contrast media for diagnostic imaging in anaesthetized dogs and cats: a retrospective study. Veterinary Anaesthesia and Analgesia 43, 502–510

Question 37

Which of the following is CORRECT:

1. There is a significant association between the resolution of tendon and ligament lesions on T2w images and a return to soundness.
2. There is a significant association between the resolution of tendon, ligament, and bone lesions on STIR images and a return to soundness.
3. Resolution of lesions on STIR images likely represents healing with a transition to chronic tissue remodeling; persistence of changes on T1w images are of unclear significance.
4. Horses with resolution on STIR images at the time of recheck MRI had a significantly decreased time to return to work.

Answer 37

CORRECT: Resolution of lesions on STIR images likely represents healing with a transition to chronic tissue remodeling; persistence of changes on T1w images are of unclear significance.

• There is a significant association between the resolution of tendon and ligament lesions on STIR images and a return to soundness.
• There is a significant association between the resolution of tendon and ligament (NOT BONE) lesions on STIR images and a return to soundness.
• No significant correlation was found between time to return to work and resolution of STIR lesions at the time of recheck MRI

HOLOWINSKI, M., JUDY, C., Saveraid, T., et al. (2010) RESOLUTION OF LESIONS ON STIR IMAGES IS ASSOCIATED WITH IMPROVED LAMENESS STATUS IN HORSES. Veterinary Radiology & Ultrasound 51, 479–484

Question 38

What is the developmental cause of a persistent left cranial vena cava?

Answer 38

Persistent left cranial vena cava occurs when the left-sided cranial venous cardinal system fails to evolve into the coronary sinus.

Lee, Y., Jung, J., Park, J., et al. (2017) CARDIAC MAGNETIC RESONANCE IMAGING OF PATENT DUCTUS ARTERIOSUS IN THREE DOGS. Veterinary Radiology & Ultrasound 58, 62–75

Question 39

Which of the following interactions between x-rays and matter is responsible for almost all scatter production?

a. Coherent scattering
b. Photoelectric effect
c. Compton scattering
d. Rayleigh scattering

At low photon energies, which interaction between x-rays and matter is responsible for enhancing natural tissue contrast?

a. Compton scattering
b. Photoelectric absorption
c. Coherent scattering
d. Rayleigh scattering

Which of the following interactions between x-rays and matter requires a minimum of 1.02MeV to occur?

a. Thompson scattering
b. Photodisintegration
c. Photoelectric effect
d. Pair production

What is the predominant interaction of 120 kV x-rays from a computed tomography scanner with soft tissue?

a. Coherent scattering
b. Compton scattering
c. Photoelectric effect
d. Pair production

Answer 39

Which of the following interactions between x-rays and matter is responsible for almost all scatter production?

a. Coherent scattering
b. Photoelectric effect

c. Compton scattering

d. Rayleigh scattering

At low photon energies, which interaction between x-rays and matter is responsible for enhancing natural tissue contrast?

a. Compton scattering

b. Photoelectric absorption

c. Coherent scattering
d. Rayleigh scattering

Which of the following interactions between x-rays and matter requires a minimum of 1.02MeV to occur?

a. Thompson scattering
b. Photodisintegration
c. Photoelectric effect

d. Pair production

What is the predominant interaction of 120 kV x-rays from a computed tomography scanner with soft tissue?

a. Coherent scattering

b. Compton scattering

c. Photoelectric effect
d. Pair production

Question 40

What is the most likely diagnosis for this patient?

Answer 40

• Cricopharyngeal achalasia
• Dorsal pharyngeal wall (DP) contracts to meet the tongue base (TB) but bolus passage is obstructed by hypertrophied cricopharyngeus muscle (black arrows). The luminal diameter of the UES is very narrow (white arrow)
• After the swallow is complete, a large amount of barium remains in the oral cavity

Pollard, R.E. (2012) Imaging Evaluation of Dogs and Cats with Dysphagia. ISRN Veterinary Science 2012, 1–15

Question 41

• What is this artifact?
• Describe what it is and why it happens.
• Which sequences are susceptible to this artifact?
• How do you minimize it? Can you fix it entirely?

Answer 41

• Truncation artifact
• Describe what it is and why it happens:
  
  • Line of abnormal signal intensity that occurs parallel to an interface between tissues of markedly different signal intensity.
• Which sequences are susceptible to this artifact?
  
  • All sequences are susceptible
• How do you minimize it? Can you fix it entirely?
  
  • Can’t completely eliminated, but can be mimized by:
    
    • ​Increasing spatial resolution
    • Pre-reconstruction filters (Hamming, Turkey)
    • Post-processing optimization techniques (Total Variation method)

Gregori, T., Lam, R., Priestnall, S.L., et al. (2016) TRUNCATION ARTIFACT IN MAGNETIC RESONANCE IMAGES OF THE CANINE SPINAL CORD. Veterinary Radiology & Ultrasound 57, 582–586

Question 42

Which cranial nerves contribute to the oropharyngeal phase of swallowing?

Answer 42

CN 5, 7, 9, 10, 12

Question 43

Wood foreign bodies:

• What are the CT features of acute wooden FB vs. chronic?
• What determines the appearance of the FB?
• What is the typical appearance of wood FB on US and MRI?

Answer 43

• What are the CT features of acute wooden FB vs. chronic?
  
  • Acute: gas in soft tissues
  • Chronic: draining tract, fat stranding, periosteal reaction, higher proportion of FB are visible
• What determines the appearance of the FB?
  
  • Over time, will absorb fluid
    
    • Increased attenuation on CT and T2w-signal on MRI
    • Decreased echogenicity on US
  • Hard wood more attenuating than soft wood
• What is the typical appearance of wood FB on US and MRI?
  
  • US: linear echogenic structure with shadowing
  • MRI:
    
    • T1 hypointense to muscle, often appears as a signal void
    • T2 variable (see above)

Lamb, C.R., Pope, E.H.W.W. & Lee, K.C.L.L. (2017) RESULTS OF COMPUTED TOMOGRAPHY IN DOGS WITH SUSPECTED WOODEN FOREIGN BODIES. Veterinary Radiology & Ultrasound 58, 144–150

Ober, C.P., Jones, J.C., Larson, M.M., et al. (2008) Comparison of ultrasound, computed tomography, and magnetic resonance imaging in detection of acute wooden foreign bodies in the canine manus. Veterinary Radiology and Ultrasound 49, 411–418

Question 44

MRI metallic artifacts associated with surgical implants and foreign material:

• Which of the metallic structures moved within the gelatin phantom?
• Which type of total hip implant produced less artifact?
• Rank the susceptibility to artifact of each sequence from greatest to least

Answer 44

• Sewing needle moved
• Titanium TH implant was better than stainless steel
• T2*-GRE >> T1w SE = T2w TSE

Sutherland-Smith, J. & Tilley, B. (2012) MAGNETIC RESONANCE IMAGING METALLIC ARTIFACT OF COMMONLY ENCOUNTERED SURGICAL IMPLANTS AND FOREIGN MATERIAL. Veterinary Radiology & Ultrasound 53, 312–317

Question 45

Diagnosis?

Answer 45

Normal dog.

Question 46

Spinal mast cell tumors in dogs:

• What is the primary location?
• What are the top differentials for MCT in the spine?
• Imaging features are highly variable, but what features were more consistent?

Answer 46

• What is the primary location?
  
  • Extradural – in the canal, paravertebral, or polyostotic
• What are the top differentials for MCT in the spine?
  
  • Lymphoma – probably the most similar
  • Multiple myeloma (more often lytic)
  • Histiocytic sarcoma (more often intradural or intramedullary)
• Imaging features are highly variable, but what features were more consistent?
  
  • STIR hyperintense
  • Mild CE

Moore, T.W., Bentley, R.T., Moore, S.A., et al. (2017) Spinal Mast Cell Tumors in Dogs: Imaging Features and Clinical Outcome of Four Cases. Veterinary Radiology and Ultrasound 58, 44–52

Question 47

What is the typical appearance of subdural hemorrhage vs. epidural hemorrhage?

Answer 47

• Subdural: crescent-shaped, can cross suture lines but is limited by falx and tentorium
• Epidural: bi-convex (lens-shaped), can cross dural folds but NOT sutures

Question 48

• What is a territorial infarct? Lacunar infarct?
• What is the typical signalment of a dog that might get a territorial infarct vs. lacunar infarct?
• What are the MRI features of an inschemic infarct?

Answer 48

• What is a territorial infarct? Lacunar infarct?
  
  • Territorial: occlusion of one of the main arteries
  • Lacunar: limited to the vascular territory of an intraparenchymal superficial or deep perforating artery
• What is the typical signalment of a dog that might get a territorial infarct vs. lacunar infarct?
  
  • Big dogs –> lacunar
  • Small dogs –> territorial
• What are the MRI features of an inschemic infarct?
  
  • Homogeneous, T2-hyper region with sharp demarcation between affected and non-affected parenchyma
  • Minimal to no mass effect
  • Typically confined to gray matter
  • Faint CE can occur
  • Reperfusion injury can result in hemorrhage

Hecht, S. & Adams, W.H. (2010) MRI of Brain Disease in Veterinary Patients Part 2: Acquired Brain Disorders. Veterinary Clinics of NA: Small Animal Practice 40, 39–63

Question 49

Regarding implant-associated neoplasia:

• What types of neoplasia are associated with orthopedic implants and which is most common?
• What is the predilection site for implant-associated neoplasia?
• What was the median time to tumor development after implant placement?
• How did prognosis compare to dogs with naturally-occuring bone tumors?

Answer 49

• What types of neoplasia are associated with orthopedic implants and which is most common?
  
  • OSA by far the most common
  • Histiocytic sarcoma, fibrosarcoma, spindle cell sarcoma
• What is the predilection site for implant-associated neoplasia? Diaphysis
• What was the median time to tumor development after implant placement? 5.5 years
• Prognosis appears to be similar to naturally-occurring disease

Burton, A.G., Johnson, E.G., Vernau, W., et al. (2015) Implant-associated neoplasia in dogs: 16 cases (1983–2013). Journal of the American Veterinary Medical Association 247, 778–785

Question 50

Gallbladder sludge in dogs:

• What was the relationship between GB volume and sludge?
• What patient-specific factors were correlated with increased volume of sludge?

Answer 50

• What was the relationship between GB volume and sludge?
  
  • Median GB volume was higher in dogs with more sludge, likely indicating abnormal emptying
• What patient-specific factors were correlated with increased volume of sludge?
  
  • Increasing age
  • HAC and hypothyroidism
  • Hepatobiliary disease
  • NOT: biochemical factors or BCS

Cook, A.K. & Jambhekar, A. V (2016) Gallbladder Sludge in Dogs: Ultrasonographic and Clinical Findings in 200 Patients. Journal of the American Animal Hospital Association 52, 125–131

Question 51

Comparison of the radiographic and tracheoscopic appearance of the dorsal tracheal membrane in large and small breed dogs (Lindl-Bylicki, 2015):

• What structure is referred to as the dorsal tracheal membrane?
• The DTM comprises a larger percentage of the tracheal circumference in dogs (with/without) tracheal collapse than in dogs (with/without) TC.
  
  • What was the proposed explanation for this finding?
• Radiographs (underestimate/overestimate) the degree and location of tracheal collapse in comparison to fluoroscopy.
• What was the prevalence of invagination of the DTM in dogs with tracheal collapse?

Answer 51

• What structure is referred to as the dorsal tracheal membrane? Trachealis muscle
• The DTM comprises a larger percentage of the tracheal circumference in dogs (with) tracheal collapse than in dogs (without) TC.
  
  • What was the proposed explanation for this finding? Flattening of the tracheal rings likely leads to stretching of the DTM
• Radiographs (overestimate) the degree and location of tracheal collapse in comparison to fluoroscopy.
• What was the prevalence of invagination of the DTM in dogs with tracheal collapse? 0%

Lindl-Bylicki, B.J., Johnson, L.R. & Pollard, R.E. (2015) COMPARISON OF THE RADIOGRAPHIC AND TRACHEOSCOPIC APPEARANCE OF THE DORSAL TRACHEAL MEMBRANE IN LARGE AND SMALL BREED DOGS. Veterinary Radiology & Ultrasound 56, 602–608

Question 52

MRI of PNST of the brachial plexus in dogs:

• What are common MRI features?
• What sequences are recommended?

Answer 52

• What are common MRI features?
  
  • About half were masses
  • 8/18 had ascending thickening; most of these extending into the vertebral canal
  • T2 hyper, T1 iso
  • Heterogeneous CE
• What sequences are recommended?
  
  • Dorsal STIR
  • Trans/sag T2
  • Trans T1 pre- and post C+
  • Smaller FOV trans of cervical spine to evaluate nerve roots

Kraft, S., Ehrhart, E.J., Gall, D., et al. (2007) Magnetic resonance imaging characteristics of peripheral nerve sheath tumors of the canine brachial plexus in 18 dogs. Veterinary Radiology and Ultrasound 48, 1–7

Question 53

Elastography of spontaneous soft tissue injuries in horses:

• What level of stiffness was associated with acute, subacute, and chronic lesions?
• What is the explanation for the differences in stiffness?
• Was there a correlation with lesion echogenicity?

Answer 53

• What level of stiffness was associated with acute, subacute, and chronic lesions?
  
  • Acute lesions = softer
  • Subacute/chronic = stiffer
• What is the explanation for the differences in stiffness?
  
  • In humans, areas of fiber disruption and hematoma formation are softer
  • As tensons heal over time, the progressive collagen deposition increases stiffness
• Was there a correlation with lesion echogenicity?
  
  • Hypoechoic lesions tend to be softer (likely more acute)

Lustgarten, M., Redding, W.R., Labens, R., et al. (2015) ELASTOGRAPHIC EVALUATION OF NATURALLY OCCURING TENDON AND LIGAMENT INJURIES OF THE EQUINE DISTAL LIMB. Veterinary Radiology & Ultrasound 56, 670–679

Question 54

• What is the upper limit for prostate size on radiography?
• What is the most likely diagnosis in neutered dogs with prostatic mineralization? What about intact dogs?

Answer 54

• A radiographically normal prostate gland has been defined as a height less than 70% of the pubic brim–sacral promontory dimension on a lateral view
• Neutered = 100% PPV carcinoma
• Intact = paraprostatic cyst, BPH, or prostatitis

BRADBURY, C.A., WESTROPP, J.L. & Pollard, R.E. (2009) RELATIONSHIP BETWEEN PROSTATOMEGALY, PROSTATIC MINERALIZATION, AND CYTOLOGIC DIAGNOSIS. Veterinary Radiology & Ultrasound 50, 167–171

Question 55

• What are the two most common types of protozoal meningoencephalitis?
• Describe their features on MRI

Answer 55

• Neosporosis: T2 hyperintensity of the vermis and cerebellar hemispheres with mild CE
• Toxoplasmosis: Multifocal, indistinct, CE parenchymal lesions, which are iso on T1 and hyper on T2 and have associated edema.

Hecht, S. & Adams, W.H. (2010) MRI of Brain Disease in Veterinary Patients Part 2: Acquired Brain Disorders. Veterinary Clinics of NA: Small Animal Practice 40, 39–63

Question 56

Sequential MRI scans of a dog with a cranial hematoma.

• List them in chronological order
• For each set of images, predict the timing post-trauma

Answer 56

• B – hyperacute (IB) – 1 hour post trauma
• A – acute (I/B D) – 3 days
• D – early subacute (ring B/D) – 5 days
• C – late subacute/chronic – 14 days
  
  • T1 iso or hypo
  • T2 center hyper, rim hypo

Tamura, S., Tamura, Y., TSUKA, T., et al. (2006) SEQUENTIAL MAGNETIC RESONANCE IMAGING OF AN INTRACRANIAL HEMATOMA IN A DOG. Veterinary Radiology & Ultrasound 47, 142–144

Question 57

Diagnosis?

Answer 57

Portocaval shunt

Question 58

• Of the intercarpal ligaments in the horse, which one(s) are the most clinically relevant and what is their function?
• What dose of contrast was given and into what structure was it injected?
• What was the the surprising finding regarding the suspensory ligament?

Answer 58

• MPICL and LPICL are most clinically relevant; function: stabilization and prevention of hyperextension
• 10-12 ml iohexol diluted 1:1 with saline into the carpal sheath
• Contrast within the proximal aspect of the suspensory ligament in all horses

Gray, S.N., Puchalski, S.M. & Galuppo, L.D. (2013) COMPUTED TOMOGRAPHIC ARTHROGRAPHY OF THE INTERCARPAL LIGAMENTS OF THE EQUINE CARPUS. Veterinary Radiology & Ultrasound 54, 245–252

Question 59

Name the labeled structures in this dorsal TOF image of a dog brain.

Answer 59

1. Rostral cerebral a.
2. Rostral communicating a.
3. Middle cerebral a.
4. Internal carotid a.
5. Caudal communicating a.
6. Caudal cerebral a.
7. Maxillary a.

Kang, B.-T., Jang, D.-P., Gu, S.-H., et al. (2009) Three-Dimensional Time-of-Flight Magnetic Resonance Angiography of Intracranial Vessels in a Canine Model of Ischemic Stroke with Permanent Occlusion of the Middle Cerebral Artery. Comparative Medicine 59, 72–77

Question 60

• What criteria can be used to assess the pulmonary veins in dogs with MMVD?
• Where was a significant difference noted between healthy dogs and dogs with MMVD?

(Oui et al., 2015)

Answer 60

• Normal dogs:
  
  • Pulmonary arteries and veins are similar in size
  • Cranial lobar vessel diameter smaller than 4th rib (lateral)
  • Most had caudal lobar veins that were larger than the 9th rib (previous criteria for enlargement)
• Proposed new cut-off with better specificity but slightly lower sensitivity than the 1:1 ratio
  
  • Right caudal PV < 1.22x width of 9th rib (VD)
• Right caudal pulmonary vein in dogs with MMVD was significantly larger than in normal dogs; the remainder of the pulmonary vessels showed no significant difference

Oui, H., Oh, J., Keh, S., et al. (2014) MEASUREMENTS OF THE PULMONARY VASCULATURE ON THORACIC RADIOGRAPHS IN HEALTHY DOGS COMPARED TO DOGS WITH MITRAL REGURGITATION. Veterinary Radiology & Ultrasound 56, 251–256

Question 61

Which cranial nerve(s) contribute to the cricopharyngeal phase of swallowing?

Answer 61

CN 10 and 12

Question 62

• What is this lesion?
• What breed is predisposed?
• What percentage of dogs of said breed that have cauda equina syndrome also have this lesion?
• Sex predilection?

Answer 62

• Sacral osteochondrosis - lesion in dorsal endplate
• ~30% of GSDs with CES have sacral OC
  
  • Clinically normal with OC <18mo
  • CES with OC >18mo
• Dogs with CES and OC were 2 years younger than CES dogs w/o OC
• Males >> females

Lang, J. & Hani, H. (1992) A SACRAL LESION RESEMBLING OSTEOCHONDROSIS IN THE GERMAN SHEPHERD DOG. Veterinary Radiology & Ultrasound 33, 69–76

Question 63

What is the most likely diagnosis in this cat with peripheral eosinophilia?

Answer 63

FGESF

Question 64

Novel radiographic ratio for vertebral canal stenosis in Great Danes:

• How is the ratio measured?
• What value confers a 90% probability of spinal cord compression at that site?
• At what sites was there a significant difference in measurement between affected and clinically normal dogs?
• As the ratio increases, how does the probability of spinal cord compression change?

Answer 64

• Ratio = A/B (see image)
• What value confers a 90% probability of spinal cord compression at that site? Ratio = 0.4
• At what sites was there a significant difference in measurement between affected and clinically normal dogs? C5-6 and C6-7
• As the ratio increases, how does the probability of spinal cord compression change? For every 0.1 incremental increase in ratio, there is a 65% decrease in the odds of spinal cord compression being present at that site

Martin-Vaquero, P. & da Costa, R.C. (2014) EVALUATION OF TRADITIONAL AND NOVEL RADIOGRAPHIC VERTEBRAL RATIOS IN GREAT DANES WITH VERSUS WITHOUT CERVICAL SPONDYLOMYELOPATHY. Veterinary Radiology & Ultrasound 55, 488–495

Question 65

• What is DISH? What are the parameters required for diagnosis?
• What are the manifestations of extra-spinal DISH?
• What is ASD?

Answer 65

• Diffuse idiopathic skeletal hyperostosis
  
  • Flowing ossifcation along the ventrolateral aspect of at least FOUR vertebral bodies without a bulge at the IVDS
  • Preservation of IVDS; no signs of IVDD
  • No fusion of articular processes, joint ankylosis, SI joint erosion, intra-articular osseous fusion
• Extra-spinal: calcification of tendons, ligaments, joint capsule
• Adjacent segment disease
  
  • Vertebral fusion > 2 consecutive IVDS was correlated with ASD = degeneration of adjacent segment

Ortega, M., Gonçalves, R., Haley, A., et al. (2012) SPONDYLOSIS DEFORMANS AND DIFFUSE IDIOPATHIC SKELETAL HYPEROSTOSIS (DISH) RESULTING IN ADJACENT SEGMENT DISEASE. Veterinary Radiology & Ultrasound 53, 128–134

Question 66

• What proportion of horses show skeletal muscle uptake of ⁹⁹Tc-HDP after a peroneal nerve block?
• In how many of these horses does this uptake resemble a lesion of the tibia?
• How long does it last?
• What was the effect of dose volume?
• What was the effect of body weight?

Answer 66

• 50% of horses will have muscle uptake
• In 20% of horses it could be mistaken for a tibial lesion
• Lasts up to 7 days
• Higher dose volume and higher BW–> increased count density

Griffin IV, J.F., Young, B.D., Fosgate, G.T., et al. (2010) FOCAL SKELETAL MUSCLE UPTAKE OF 99mTECHNETIUM-HYDROXYMETHYLENE Diphosphonate FOLLOWING PERONEAL NERVE BLOCKS IN HORSES. Veterinary Radiology & Ultrasound 51, 338–343

Question 67

• What is the appearance of a patent intracranial aneurysm on MRI or CT?

Answer 67

• What is the appearance of a patent intracranial aneurysm on MRI or CT?
  
  • Flow void on T1/T2 images
  • Expansile, strongly-enhancing mass along the intracranial cavernous sinus

Hecht, S. & Adams, W.H. (2010) MRI of Brain Disease in Veterinary Patients Part 2: Acquired Brain Disorders. Veterinary Clinics of NA: Small Animal Practice 40, 39–63

Question 68

• What are the common anatomical variants of the spinous process of C7 in horses?
• What are the common variants of the T1 spinous process?
• What variation was seen associated with C6?

Answer 68

• What are the common anatomical variants of the spinous process of C7 in horses?
  
  • Sharp triangular shape, rounded triangular shape, spur-like shape
• What are the common variants of the T1 spinous process?
  
  • High and pronounced or short and squat
• What variation was seen associated with C6?
  
  • Transposition of the ventral aspect onto C7
  • Small center of ossification at the caudal limit of the ventral process

Santinelli, I., Beccati, F., Arcelli, R., et al. (2015) Anatomical variation of the spinous and transverse processes in the caudal cervical vertebrae and the first thoracic vertebra in horses. Equine Veterinary Journal 48, 45–49

Question 69

Regarding trans-splenic portal scintigraphy:

• What is the dose range of ^99mTcO₄^- ?
• How is this procedure performed?
• How is shunt fraction calculated?
• What is the normal transit time from liver to heart?

Answer 69

• What is the dose range of ^99mTcO₄^- ?
  
  • 0.5-2 mCI = 35-75 MBq
• How is this procedure performed?
  
  • Dose injected into spleen using US-guidance and 22g needle (shielded syringe obvi)
  • Dynamic frame-mode acquisition initiated after needle placement within the spleen and approximately 2 s prior to injection of 99mTcO4
  • Images acquired at a frame rate of 4 fps for 5 min
  • Stored in 128 x 128 x 16 matrix
• How is shunt fraction calculated?
  
  • SF = Heart counts / (Heart counts + Liver counts)
    
    • Where these counts are summed over 7 sec beginning at first arrival of radionuclide in liver or heart
• What is the normal transit time from liver to heart?
  
  • 5-10 sec (mean 7 sec)

Morandi, F., Cole, R.C., Tobias, K.M., et al. (2005) USE OF 99MTCO TRANS-SPLENIC PORTAL SCINTIGRAPHY FOR DIAGNOSIS OF PORTOSYSTEMIC SHUNTS IN 28 DOGS. Veterinary Radiology & Ultrasound 46, 153–161

Question 70

What is the most likely diagnosis in this cat that is acutely blind?

Answer 70

Pituitary apoplexy secondary to macroadenoma

Beltran, E., Dennis, R., Foote, A., et al. (2012) IMAGING DIAGNOSIS-PITUITARY APOPLEXY IN A CAT. Veterinary Radiology & Ultrasound 53, 417–419

Question 71

Regarding complications due to the use of a Tru-cut biopsy gun in cats:

• Which device was associated with more complicatons and what was the proposed cause of this difference?
• What was the nature of these complications?

Answer 71

• Which device was associated with more complicatons and what was the proposed cause of this difference?
  
  • Automatic biopsy device
  • No complications with semi-automatic device
  • Theory: automatic device induced intense vagotonia possibly due to increased force (14 lbf vs. 9 lbf in a different study with no fatalities)
• What was the nature of these complications?
  
  • Fatal shock reactions: bradycardia, hypotension, hypoventilation
  • 1/5 of these patients had a necropsy and no hemorrhage was identified

Proot, S.J.M. & Rothuizen, J. (2006) High Complication Rate of an Automatic Tru-Cut Biopsy Gun Device for Liver Biopsy in Cats. Journal of Veterinary Internal Medicine 20, 1327–1333

Question 72

Preureteral vena cava:

• Why does this occur?
• Describe the course of the ureter; what is the proportion of left vs. right-sided precaval ureters?
• What additional vascular anomaly is sometimes found with the condition?
• What is the clinical significance of this condition?
• What is the prevalence?

Answer 72

• Why does this occur?
  
  • Failure of regression of the right caudal cardinal vein
• Describe the course of the ureter; what is the proportion of left vs. right-sided precaval ureters?
  
  • Ureter courses medially at the level of L4/5, passing dorsal to the cava, then wraps around the contralateral side of the cava, coursing ventrally back toward its side of origin toward the bladder (reverse J-shape)
  • Right >>> left-sided
• What additional vascular anomaly is sometimes found with the condition?
  
  • Double vena cava
• What is the clinical significance of this condition?
  
  • Increased risk of urinary tract signs
• Prevalence = 25%

Pey, P., Marcon, O., Drigo, M., et al. (2015) MULTIDETECTOR-ROW COMPUTED TOMOGRAPHIC CHARACTERISTICS OF PRESUMED PREURETERAL VENA CAVA IN CATS. Veterinary Radiology & Ultrasound 56, 359–366

Question 73

According to a 1997 study, what were the typical sonographic features of parathyroid lesions? Were there any distinguishing features between neoplastic and non-neoplastic lesions?

Answer 73

• All parathyroid lesions were round or oval-shaped and hypoechoic to the thyroid parenchyma. Some had distal acoustic enhancement.
• Significant difference in size between neoplastic and non-neoplastic nodules.
• All neoplastic nodules were > 4mm in maximum dimension
• All but one hyperplastic nodules were < 4mm – this larger one was secondary to CKD

Wisner, VRU 1997 38(6)

Question 74

Regarding nasopharyngeal polyps in cats:

• What are the typical CT features?
• What is the significance of the superficial stroma?

Answer 74

• CT features:
  
  • Hypoattenuating to muscle; isoattenuating to soft tissue
  • Rim enhancement
  • Pedunculated with a stalk through the auditory tube to the affected bulla
  • Complete or partial obliteration of bulla lumen with ST attenuating material
    
    • Minimal osteolysis; uncommon
  • Expansion and thickening of the bulla wall
  • MRLNpathy commonly ipsilateral, can be bilateral
• Rim enhancement is positively correlated to inflammation of the superficial stroma and negatively correlated to edema in the superficial stroma

Oliveira, C.R., O’Brien, R.T., MATHESON, J.S., et al. (2012) COMPUTED TOMOGRAPHIC FEATURES OF FELINE NASOPHARYNGEAL POLYPS. Veterinary Radiology & Ultrasound 53, 406–411

Lamb, C.R., Sibbing, K. & Priestnall, S.L. (2016) PATHOLOGIC BASIS FOR RIM ENHANCEMENT OBSERVED IN COMPUTED TOMOGRAPHIC IMAGES OF FELINE NASOPHARYNGEAL POLYPS. Veterinary Radiology & Ultrasound 57, 130–136

Question 75

What are the 3 vascular patterns described on CEUS of dogs with pituitary-dependent HAC? What is the normal CE pattern?

Answer 75

Normal: central vessel –> radial vessels –> homogeneous CE with phrenicoabdominal vein visible

Three Abnormal Patterns in PDH:

1. central vessel –> disorderly uptake in the entire gland –> homogeneous CE
2. no central vessel –> disorderly uptake in the entire gland –> homogeneous CE
3. abnormal, nodular-appearing vessels –> progressive nodular appearance –> homogeneous CE

Question 76

What is the normal CE pattern of the spleen on CEUS?

Answer 76

Small splenic arteries become visible –> heterogeneous enhancement in the early phase –> homogeneous at peak CE

Rossi, F., Fina, C., Stock, E., et al. (2016) EFFECT OF SEDATION ON CONTRAST-ENHANCED ULTRASONOGRAPHY OF THE SPLEEN IN HEALTHY DOGS. Veterinary Radiology & Ultrasound 57, 276–281

Question 77

What were the significant findings related to contrast-enhanced ultrasonography of canine insulinomas?

Nakamura, K., Lim, S.-Y., Ochiai, K., et al. (2014) CONTRAST-ENHANCED ULTRASONOGRAPHIC FINDINGS IN THREE DOGS WITH PANCREATIC INSULINOMA. Veterinary Radiology & Ultrasound 56, 55–62

Answer 77

• All pancreatic nodules were visible on B-mode ultrasound
• CEUS resulted in increased conspicuity of the nodules and better demarcation of their margins.
• CE patterns were different in all three nodules (hyperechoic for 5 sec, mildly hyperechoic for 1 sec, hypoechoic for over 30 sec)

Question 78

Comparing 3V CXR to thoracic CT:

• How did CXR compare to CT for the identification of pulonary nodules (i.e. what % were detected on rads)?
• In which dogs (signalment, disease) were nodules detected only on CT?
• (T/F): Rads have an excellent PPV but poor NPV for pulmonary nodules
• Fill in the blank: One third of the pulmonary nodules identified on CT had a ________ distribution.

Answer 78

* How did CXR compare to CT for the identification of pulonary nodules (i.e. what % were detected on rads)?

* CXR identified 80% of cases with nodules * In which dogs (signalment, disease) were nodules detected only on CT?
* Large breed dogs with OSA * (F): Rads have an excellent PPV **AND MODERATE (65-90%)** NPV for pulmonary nodules * Fill in the blank: One third of the pulmonary nodules identified on CT had a SUBPLEURAL distribution.

Armbrust, L., Biller, D.S. & Bamford, A. (2012) Comparison of three-view thoracic radiography and computed tomography for detection of pulmonary nodules in dogs with neoplasia. Journal of the American Veterinary Medical Association 240, 1088–1094

Question 79

Lung lobe torsion in dogs:

• How often is there concurrent/underlying(?) thoracic disease?
• What are the radiographic features of LLT?
• What are the predilection sites for LLT?

Answer 79

• How often is there concurrent/underlying(?) thoracic disease?
  
  • D’Anjou et al – 5/13 dogs had concurrent disease
    
    • Immune-mediate pyogranulomatous pleuritis/pericarditis/mediastinitis
    • Heart base tumor
    • Malignant histiocytosis of torsed lobe
    • TVD
  • Latimer et al
    
    • Pneumonia
    • Bullous emphysema
    • Maybe bronchial cartilage dysplasia in brachycephalics?
• What are the radiographic features of LLT?
  
  • Pleural effusion
  • Mediatinal shift (can go either way)
  • Increased opacity of lobe, loss of visualization of vasculature (100%)
  • Vesicular pattern in some dogs vs. uniform alveolar in others
  • Narrowed +/- displaced bronchus
• What are the predilection sites for LLT?
  
  • Right middle and left cranial lobes
• Predominance of males

Latimer, C.R., Lux, C.N., Sutton, J.S., et al. (2017) Lung lobe torsion in seven juvenile dogs. Journal of the American Veterinary Medical Association 251, 1256–1450

D’Anjou, M.-A., Tidwell, A.S. & Hecht, S. (2005) RADIOGRAPHIC DIAGNOSIS OF LUNG LOBE TORSION. Veterinary Radiology & Ultrasound 46, 478–484

Question 80

When interpreting MRI of the plantar tarsal region in horses, which structure has the most variable appearance?

A: DDFT

B: SDFT

C: Suspensory ligament

D: Long plantar ligament

Answer 80

C

I give up on this paper.

Question 81

• How does diffusion weighted imaging work?
• What is ADC and how is it calculated?
• What is T2 shine through?

Answer 81

• How does diffusion weighted imaging work?
  
  • Diffusion gradient pulse excites –> second diffusion gradient pulse of equal strenth and duration in opposite direction
  • For stationary water, the second pulse restores original phase of protons –> coherent signal
  • For moving water, the second pulse cannot restore to the original phase because protons are in a different configuration/location –> dephased protons lead to loss of signal
• What is ADC and how is it calculated?
  
  • Quantitative measure of water movement calculated from at least 2 trace-weighted images with different b-values
• What is T2 shine through?
  
  • Hyperintensities on the trace images due to free water diffusion, which remain hyperintense on the ADC map

Sutherland-Smith, J., KING, R., Faissler, D., et al. (2011) MAGNETIC RESONANCE IMAGING APPARENT DIFFUSION COEFFICIENTS FOR HISTOLOGICALLY CONFIRMED INTRACRANIAL LESIONS IN DOGS. Veterinary Radiology & Ultrasound 52, 142–148

Question 82

What is the effect of butorphanol on CEUS of the spleen? What about dexmedetomidine?

Answer 82

No effect of torb

Dex causes reduced enhancement, appears diffusely hypoechoic. Measured parameters of time were all delayed (AT, TTP, wash-in) and peak intensity was reduced.

Rossi, F., Fina, C., Stock, E., et al. (2016) EFFECT OF SEDATION ON CONTRAST-ENHANCED ULTRASONOGRAPHY OF THE SPLEEN IN HEALTHY DOGS. Veterinary Radiology & Ultrasound 57, 276–281

Question 83

Variation of a horse’s stance can affect radiographic measurements of hoof balance. Which of the following measurements tend to be affected by these variations:

1. Distal phalanx angle
2. DIPJ angle
3. PIPJ angle
4. Lateral and medial joint spaces of the DIPJ
5. Lateral and medial joint spaces of the PIPJ
6. Hoof pastern axis

Answer 83

(Bold = affected by varied stance)

1. Distal phalanx angle
2. DIPJ angle
3. PIPJ angle
4. Lateral and medial joint spaces of the DIPJ
5. Lateral and medial joint spaces of the PIPJ
6. Hoof pastern axis

Pauwels, F.E., Rogers, C.W., Wharton, H., et al. (2017) Radiographic Measurements of Hoof Balance Are Significantly Influenced By a Horse’S Stance. Veterinary Radiology and Ultrasound 58, 10–17

Question 84

What were the important factors in optimizing CT protocols for metallic gunshot head trauma in a seal? What factors did not result in improved image quality?

Answer 84

Minimized artifacts with: high frequency image reconstruction algorithm, WIDE window setting, proprietary extended CT scale raw data reconstruction (ECTS) also with extra WIDE window setting

Increasing tube voltage and use of beam-hardening reduction (PFO) filter did not significantly reduce metal artifacts

Question 85

Occlusion of what vessel(s) is indicated by the arrows in this image?

Answer 85

Middle cerebral a. and internal carotid a. (although caption in the paper says internal cerebral a.) with concurrent attenuation of the rostral communicating a.

Kang, B.-T., Jang, D.-P., Gu, S.-H., et al. (2009) Three-Dimensional Time-of-Flight Magnetic Resonance Angiography of Intracranial Vessels in a Canine Model of Ischemic Stroke with Permanent Occlusion of the Middle Cerebral Artery. Comparative Medicine 59, 72–77

Question 86

• What condition is illustrated by these images?
• What is the most likely signalment of this patient?
• Is this a typical location for this lesion?
• Would you expect contrast enhancement of the endplate(s)?

Answer 86

• Osteochondrosis, most likely in a young GSD.
• LS junction most common
• CE common

GENDRON, K., DOHERR, M.G., Gavin, P., et al. (2012) MAGNETIC RESONANCE IMAGING CHARACTERIZATION OF VERTEBRAL ENDPLATE CHANGES IN THE DOG. Veterinary Radiology & Ultrasound 53, 50–56

Question 87

Diagnosis?

Answer 87

Portoazygous shunt

Question 88

CT features of pharyngeal neoplasia in dogs:

• What are the most common types of oropharyngeal neoplasia?
• What are the common and uncommon CT features of pharyngeal neoplasia?
• What significant findings were reported about lymphadenopathy? (Which LN were affected and at what rate?)

Answer 88

• What are the most common types of oropharyngeal neoplasia?
  
  • Malignant melanoma, SCC, FSA
• What are the common and uncommon CT features of pharyngeal neoplasia?
  
  • Space-occupying masses with irregular shape and ill-defined margins
  • Moderate to marked CE
  • Oropharynx > laryngopharynx > nasopharynx
  • Uncommon: osteolysis of adjacent structures, infiltration of vessels, mineralization
• What significant findings were reported about lymphadenopathy? (Which LN were affected and at what rate?)
  
  • MRLN most commonly abnormal (96%) in size, shape, or abnormal enhancement.
  • 50% metastatic MRLN

Carozzi, G., Zotti, A., Alberti, M., et al. (2015) Computed tomographic features of pharyngeal neoplasia in 25 dogs. Veterinary Radiology and Ultrasound 56, 628–637

Question 89

• Which scintigraphic measurement has the highest sensitivity and specificity for hyperthyroidism in cats?
• Which scintigraphic measurement is most closely associated with serum T4?
• What is the normal range for each of these values?
• When should methimazole be stopped in preparation for the exam?

Answer 89

• T/S ratio most se/sp
• % uptake (TcTU) is most closely associated with serum T4
• Normals:
  
  • T/S: up to 1.1 (or 1.5 depending on the study)
  • TcTU: 0.4% mean (<1% max)
• 7-10 days should be sufficient

Peterson, M.E., Guterl, J.N., Rishniw, M., et al. (2016) EVALUATION OF QUANTITATIVE THYROID SCINTIGRAPHY FOR DIAGNOSIS AND STAGING OF DISEASE SEVERITY IN CATS WITH HYPERTHYROIDISM: COMPARISON OF THE PERCENT THYROIDAL UPTAKE OF PERTECHNETATE TO THYROID-TO-SALIVARY RATIO AND THYROID-TO-BACKGROUND RATIOS. Veterinary Radiology & Ultrasound 57, 427–440

Question 90

• Are intra- and intervertebral ratios good for differentiating normal from CVM in Dobermans?
• How do the ratios change with location along the cervical spine (general)?
• How is the morphology of the cervical vertebral canal described in these dogs?

Answer 90

• No difference in either the intervertebral or intravertebral ratio between normal vs. affected dogs
• In all dogs (normal and CVM), ratios decreased progressively along the cervical spine, being smallest at C6–C7
• Funnel-shaped, caudally tapering cervical vertebral canal

da Costa, R.C. & Johnson, J.A. (2012) INTERVERTEBRAL AND INTRAVERTEBRAL RATIOS IN DOBERMAN PINSCHER DOGS WITH CERVICAL SPONDYLOMYELOPATHY. Veterinary Radiology & Ultrasound 53, 518–523

Question 91

What is the effect of positioning a patient in lateral recumbency on your swallow study?

Answer 91

Increases transit time in the cervical esophagus, fewer primary peristaltic waves.

Question 92

• What is the most common radiographic pattern of NCPE?
• What findings were specifically noted for post-obstructive NCPE?
• Was there a lobe predilection?
• What features are predictive of survival?

Answer 92

• Most common: mixed pattern, bilateral and symmetrical, multifocal, peripheral and dorsal
• Post-obstructive: asymmetric, unilateral, dorsal distribution (did not reach significance)
• When unilateral, most often R caudal lung lobe
• No features differed between survivors and non-survivors

Bouyssou, S., Specchi, S., Desquilbet, L., et al. (2017) RADIOGRAPHIC APPEARANCE OF PRESUMED NONCARDIOGENIC PULMONARY EDEMA AND CORRELATION WITH THE UNDERLYING CAUSE IN DOGS AND CATS. Veterinary Radiology & Ultrasound 58, 259–265

Question 93

• What radiographic features of feline hip dysplasia are different from dogs?
• What are the causes of feline DJD (6)?

Answer 93

• What radiographic features of feline hip dysplasia are different from dogs?
  
  • Remodeling/proliferation of cranial acetabulum
  • Minimal remodeling of the femoral neck
• What are the causes of feline DJD (6)?
  
  • Trauma
  • Hip dysplasia
  • Primary OA (Scottish Fold OCD, MPS)
  • Nutritional (Vit. A)
  • Immune-mediated polyarthropathy (rheumatoid, SLE, periosteal proliferative polyarthritis, idiopathic)
  • Infectious (mycoplasma, cryptococcosis)

LASCELLES, B.D.X. (2010) Feline Degenerative Joint Disease. Veterinary Surgery 39, 2–13

Question 94

What are the common sonographic abnormalities found in cats with cholangitis? Were there any features specific to either neutrophilic or lymphocytic cholangitis?

Answer 94

Can be normal, but common abnormalities include gallbladder debris, common bile duct dilation, liver enlargement, hyperechoic liver parenchyma, and an enlarged pancreas.

No significant difference, but cats with neutrophilic cholangitis seemed more likely to have changes consistent with pancreatitis.

Marolf, A.J., Leach, L., Gibbons, D.S., et al. (2012) Ultrasonographic Findings of Feline Cholangitis. Journal of the American Animal Hospital Association 48, 42–46

Question 95

• What is the typical appearance of the lateral patellar ligament as it is followed in a transverse plane from the patella to its insertion at ______?
• (T/F): As asymmetry was commonly noted between contralateral ligaments in the same horse, comparison is unlikely to yield helpful findings.

Answer 95

• What is the typical appearance of the lateral patellar ligament as it is followed in a transverse plane from the patella to its insertion at ______?
  
  • Inserts on the tibial tuberosity
  • Bilayered, somewhat indistinct appearance at its origin –> flat, bilobed appearance over the lateral trochlear ridge –> flattened oval shape with irregular margins as it crosses the joint –> flat oval to triangular at insertion
  • Mixed echogenicity/texture and fiber pattern
• Although some symmetry was noted between contralateral ligaments in the same horse, comparison is still recommended since injuries tend to be much more dramatic than normal variation.

Gottlieb, R., Whitcomb, M.B., Vaughan, B., et al. (2015) Ultrasonographic appearance of normal and injured lateral patellar ligaments in the equine stifle. Equine Veterinary Journal 48, 299–306

Question 96

MRA of PSS in dogs (Seguin, 1999):

• Sensitivity and specificity of MRA in detection of any type of shunt?
• How were sensitivity and specificity affected by shunt type (MAPSS vs. single congenital)?
• How accurate was classification of intra- vs. extra-hepatic PSS?
• (T/F): Origin of shunt was more difficult to identify than insertion
• What was the appearance of MAPSS in this study?

Answer 96

• Sensitivity and specificity of MRA in detection of any type of shunt?
  
  • 80% / 100%
• How were sensitivity and specificity affected by shunt type (MAPSS vs. single congenital)?
  
  • Lower sensitivity for MAPSS than single congenital
  • Specificity unchanged
• How accurate was classification of intra- vs. extra-hepatic PSS?
  
  • Misclassified 17%
• (TRUE): Origin of shunt was more difficult to identify than insertion
• MAPSS weren’t actually visible, but were inferred due to microhepatia and diminished PV signal
  
  • This is due to too small of a volume of blood flowing through these vessels

Seguin, B., Tobias, K.M. & Gavin, P.R. (1999) USE OF MAGNETIC RESONANCE ANGIOGRAPHY FOR DIAGNOSIS OF PORTOSYSTEMIC SHUNTS IN DOGS. Veterinary Radiology & Ultrasound 40, 251–258

Question 97

What is the sex of this lizard?

Answer 97

Male

Di Ianni, F., Volta, A., Pelizzone, I., et al. (2014) DIAGNOSTIC SENSITIVITY OF ULTRASOUND, RADIOGRAPHY AND COMPUTED TOMOGRAPHY FOR GENDER DETERMINATION IN FOUR SPECIES OF LIZARDS. Veterinary Radiology & Ultrasound 56, 40–45

Question 98

• What is Q_s/Q_p?
• How is it calculated?
• What is the proposed clinical significance?

Answer 98

• Q_s/Q_p is a measure of the magnitude of a cardiovascular shunt (systemic flow / pulmonary flow).
• Q_s/Q_p = SV_LV / SV _RV
• Q_s/Q_p < 1 is considered insignificant; up to 2 is borderline

Lee, Y., Jung, J., Park, J., et al. (2017) CARDIAC MAGNETIC RESONANCE IMAGING OF PATENT DUCTUS ARTERIOSUS IN THREE DOGS. Veterinary Radiology & Ultrasound 58, 62–75

Question 99

Accuracy of CT in determining lesion size in canine appendicular OSA:

• What is the best predictor of lesion length? Did it over- or underestimate lesion length?
• What tumor features were poor predictors of length and did they typically over- or underestimate?

Answer 99

• What is the best predictor of lesion length? Did it over- or underestimate lesion length?
  
  • Intramedullary/endosteal abnormalities were best
  • Mean overestimation of 1.8%
  • But did over and underestimate by up to 30% in some patients
• What tumor features were poor predictors of length and did they typically over- or underestimate?
  
  • Periosteal reaction and CE both overestimated by an average of 9% but went in both directions (under and over)
  • Tumor necrosis may have contributed as necrotic areas would not enhance, but would add to length of mass – this may account for some underestimates

Karnik, K.S., Samii, V.F., Weisbrode, S.E., et al. (2012) ACCURACY OF COMPUTED TOMOGRAPHY IN DETERMINING LESION SIZE IN CANINE APPENDICULAR OSTEOSARCOMA. Veterinary Radiology & Ultrasound 53, 273–279

Question 100

• In a study of cMRI in dogs with PDA, how accurate were measurements of ductal diameter?

Answer 100

• Only 2 of 3 dogs went to surgery, but both had measurements on MRI within 1mm of measured diameter in surgery.

Lee, Y., Jung, J., Park, J., et al. (2017) CARDIAC MAGNETIC RESONANCE IMAGING OF PATENT DUCTUS ARTERIOSUS IN THREE DOGS. Veterinary Radiology & Ultrasound 58, 62–75

Question 101

Name the structures indicated by the colored arrows

Answer 101

• White: Long plantar ligament
• Yellow: Lateral digital flexor tendon
• Green: Plantar aspect of the tarsal sheath, extending from the calcaneus around the LDFT
• Pink: Medial digital flexor tendon

Dyson, S., Blunden, A. & Murray, R. (2017) Magnetic Resonance Imaging, Gross Postmortem, and Histological Findings for Soft Tissues of the Plantar Aspect of the Tarsus and Proximal Metatarsal Region in Non-Lame Horses. Veterinary Radiology and Ultrasound 58, 216–227

Question 102

In the Latimer et al. paper regarding lung lobe torsions in juvenile dogs (<12 mo), which lung lobes were affected most commonly and in what order?

Answer 102

n the Latimer et al. paper regarding lung lobe torsions in juvenile dogs (<12 mo), which lung lobes were affected most commonly and in what order?

• Left cranial lung lobe
• Right middle lung lobe
• Right cranial lung lobe

This paper consisted of mostly pugs, which are predisposed to L Cr LLT. The two non-pugs in this paper did not have torsions of L Cr.

Latimer, C.R., Lux, C.N., Sutton, J.S., et al. (2017) Lung lobe torsion in seven juvenile dogs. Journal of the American Veterinary Medical Association 251, 1256–1450

Question 103

• Name the numbered structures.
• What is indicated by the asterisks?
• What imaging technique was used to obtain these images and what is the advantage of this technique?
• Which technique can be used to selectively image venous or arterial flow?

Answer 103

• Name the numbered structures.
  
  • 1. CVC
  • 2. Aorta
  • 3. PV
• What is indicated by the asterisks?
  
  • Portophrenic shunt
• What imaging technique was used to obtain these images and what is the advantage of this technique?
  
  • CE-MRA – much faster scan time than TOF-MRA
• TOF-MRA allows for selective imaging, however tortuous vessels may lead to signal void

Bruehschwein, A., Foltin, I., Flatz, K., et al. (2010) Contrast-enhanced magnetic resonance angiography for diagnosis of portosystemic shunts in 10 dogs. Veterinary Radiology and Ultrasound 51, 116–121

Question 104

Femoral capital physeal closure time for cats and dogs?

Answer 104

Cats: 7-11 months

Dogs: 8-11 months

Source: Thrall normal variants textbook

Question 105

Optimized CT protocol for brain imaging

Using a fixed protocol of 120 kVP and 10cm FOV, what were the optimal settings for each of the following parameters and why?

• Scan mode
• mAs
• Slice thickness
• Tube rotation time
• Reconstruction algorithm
• Correction filter

Answer 105

• Sequential scan mode for optimal resolution
• 300 mAs for reduced noise
• 1mm slice thickness for improved longitudinal resolution
• 1 sec tube rotation time (just because)
• Medium frequency reconstruction algorithm for optimal contrast resolution
• Beam hardening correction filter (PFO)

Zarelli, M., Schwarz, T., Puggioni, A., et al. (2014) AN OPTIMIZED PROTOCOL FOR MULTISLICE COMPUTED TOMOGRAPHY OF THE CANINE BRAIN. Veterinary Radiology & Ultrasound 55, 387–392

Question 106

Regarding radiography of enterolithiasis in horses:

• What was the relative sensitivity and specificity for diagnosis?
• How did detection of small colon enteroliths compare to the large colon?
• In what segment of the colon was the sensitivity highest and for what number of enteroliths?

Answer 106

• What was the relative sensitivity and specificity for diagnosis?
  
  • SE 85%; SP 96%
• How did detection of small colon enteroliths compare to the large colon?
  
  • Lower sensitivity
  • Small colon detection negatively affected by degree of gas distension
• In what segment of the colon was the sensitivity highest and for what number of enteroliths?
  
  • Transverse colon
  • 2-5 enteroliths

Kelleher, M.E., Puchalski, S.M. & Drake, C. (2014) Use of digital abdominal radiography for the diagnosis of enterolithiasis in equids: 238 cases (2008–2011). Journal of the American Veterinary Medical Association 245, 126–129

Question 107

What is twinkle artifact?

What factors will increase twinkle artifact?

Answer 107

Twinkle artifact occurs deep to a strongly reflective surface, appearing as a quickly fluctuating mixture of Doppler signals. This occurs due to a narrow band signal error.

Dependent on size and surface texture of a structure, but not mineral composition.

Louvet, A. (2006) TWINKLING ARTIFACT IN SMALL ANIMAL COLOR-DOPPLER SONOGRAPHY. Veterinary Radiology & Ultrasound 47, 384–390

Question 108

What sonographic features of TCC are correlated with prognosis and how good are we at identifying them?

Answer 108

• Decreased MST with:
  
  • Wall involvement
  • Heterogeneous echotexture (possible necrosis)
  • Trigonal location
• Very good agreement between US indication of wall involvement and histological findings

Hanazono, K., Fukumoto, S., Endo, Y., et al. (2014) ULTRASONOGRAPHIC FINDINGS RELATED TO PROGNOSIS IN CANINE TRANSITIONAL CELL CARCINOMA. Veterinary Radiology & Ultrasound 55, 79–84

Question 109

According to a 2014 study of incidental thyroid nodules in hypercalcemic dogs found on cervical ultrasound:

• What types of nodules were identified?
• What were the sonographic features that could be used to differentiate them?

Answer 109

• Adenomas, cysts, adenocarcinoma, and nodular hyperplasia were identified.
• No sonographic features could be used to differentiate these lesions.

Pollard, R.E., Bohannon, L.K. & Feldman, E.C. (2014) PREVALENCE OF INCIDENTAL THYROID NODULES IN ULTRASOUND STUDIES OF DOGS WITH HYPERCALCEMIA (2008-2013). Veterinary Radiology & Ultrasound 56, 63–67

Question 110

How would you characterize this set of images?

Answer 110

Normal.

Pollard, R.E. (2012) Imaging Evaluation of Dogs and Cats with Dysphagia. ISRN Veterinary Science 2012, 1–15

Question 111

How does 40mcg/kg dexmedetomidine IM influence the size of the cardiac silhouette on different views in cats?

Answer 111

• Dexmedetomidine was associated with a small but significant increase in cardiac silhouette size:
  
  • Right lateral (vertebral heart score)
  • VD/DV (percentage width)
• Enlargement may be persistent at a minimum of two hours postdexmedetomidine reversal

Zwicker, L.A., Matthews, A.R., Côté, E., et al. (2016) the Effect of Dexmedetomidine on Radiographic Cardiac Silhouette Size in Healthy Cats. Veterinary Radiology & Ultrasound 57, n/a-n/a

Question 112

What is the unlabeled structure? What muscle originates here?

Answer 112

Suprahamate process in a cat – origin of the deltoideus m.

Question 113

Which scintigraphic measurement is most sensitive for detecting hyperthyroidism in cats?

Which measure correlates most closely with serum T4?

What are the three T/B ratios that can be performed, and which one is most sensitive?

Answer 113

• T/S ratio is the most sensitive
• TcTU (% uptake) is most associated with T4
• T/B (axilla, heart, trachea) – heart has best sensitivity

Peterson, M.E., Guterl, J.N., Rishniw, M., et al. (2016) EVALUATION OF QUANTITATIVE THYROID SCINTIGRAPHY FOR DIAGNOSIS AND STAGING OF DISEASE SEVERITY IN CATS WITH HYPERTHYROIDISM: COMPARISON OF THE PERCENT THYROIDAL UPTAKE OF PERTECHNETATE TO THYROID-TO-SALIVARY RATIO AND THYROID-TO-BACKGROUND RATIOS. Veterinary Radiology & Ultrasound 57, 427–440

Question 114

How does the ejection fraction compare between the following groups of dogs/gallbladders: normal, mobile sludge, immobile sludge, mucocele?

What about the GB volume?

Answer 114

EJECTION FRACTION

• DECREASED in all groups compared to normal dogs
• Mobile sludge EF > immobile = mucocele

VOLUME: INCREASED in all groups compares to normal dogs; largest in mucocele group

Tsukagoshi, T., Ohno, K., Tsukamoto, A., et al. (2011) DECREASED GALLBLADDER EMPTYING IN DOGS WITH BILIARY SLUDGE OR GALLBLADDER MUCOCELE. Veterinary Radiology & Ultrasound 53, 84–91

Question 115

What is a normal gallbladder ejection fraction (EF)? How is a standard GB EF study performed?

Answer 115

12 hour fast –> measure GB volume –> feed a standardized meal +/- administer erythromycin –> re-measure GB at set time points within 2 hours of meal.

Normal EF > 25% within 2 hours

Tsukagoshi, T., Ohno, K., Tsukamoto, A., et al. (2011) DECREASED GALLBLADDER EMPTYING IN DOGS WITH BILIARY SLUDGE OR GALLBLADDER MUCOCELE. Veterinary Radiology & Ultrasound 53, 84–91

Question 116

Feline pregnancy timeline on radiographs:

• What is a typical gestation time?
• Time of mineralization (mean days prior to parturition):
  
  • First detectable mineralization
  • Skull/ribs
  • Scapula/Humerus/Femur/Pelvis/Tibia
  • Metacarpals/metatarsals
  • Phalanges/teeth

Answer 116

• Gestation: 64 d
• First detectable mineralization: 26 dpp
  
  • Dogs: 20dpp
• Skull/ribs: 22 dpp
• Scapula/Humerus/Femur/Pelvis/Tibia: 20 dpp
• Metacarpals/metatarsals: 8 dpp
• Phalanges/teeth: 2 dpp

Haney, D.R., Levy, J.K., Newell, S.M., et al. (2003) Use of fetal skeletal mineralization for prediction of parturition date in cats. Journal of the American Veterinary Medical Association 223, 1614–1616

Question 117

What is the general pattern of contrast enhancement in the feline small bowel?

Answer 117

1. Rapid, intense enhancement of the serosa and submucosa
2. Gradual enhancement of the remainder of the wall
3. At peak enhancement, loss of demarcation between wall layers
4. Slow wash-out, with submucosa wash out occurring last

Diana, A., Specchi, S., Baron Toaldo, M., et al. (2011) CONTRAST-ENHANCED ULTRASONOGRAPHY OF THE SMALL BOWEL IN HEALTHY CATS. Veterinary Radiology & Ultrasound 52, 555–559

Question 118

Use of MDCT in the assessment of dogs with pericardial effusion:

• Causes of pericardial effusion
• What percentage of masses identified on echo were identified on CT?
• What advantage is conferred by MDCT over echo?

Answer 118

• Causes of pericardial effusion:
  
  • Neoplasia (HSA, chemodectoma, mesothelioma)
  • Idiopathic pericarditis
  • Congenital pericardial disease
  • Trauma
  • Infection
• What percentage of masses identified on echo were identified on CT? 100%
• What advantage is conferred by MDCT over echo?
  
  • Ability to assess for pulmonary mets or abdominal lesions

Scollan, K.F., Bottorff, B., Stieger-Vanegas, S., et al. (2014) Use of Multidetector Computed Tomography in the Assessment of Dogs with Pericardial Effusion. Journal of Veterinary Internal Medicine 29, 79–87

Question 119

For each of the following opacification patterns, list the differentials to be considered:

• Good initial opacification, which gradual decreases over time
• Fair/good initial opacification, which persists or increases over time
• Poor initial opacification, which persists or decreases over time
• Poor initial opacification, which increases over time
• No opacification

Answer 119

• Good initial opacification, which gradual decreases over time
  
  • Normal
• Fair/good initial opacification, which persists or increases over time
  
  • Contrast reaction – hypotension, acute tubular obstruction or necrosis, acute renal failure
• Poor initial opacification, which persists or decreases over time
  
  • Primary renal disease (polyuric RF, glomerular dz)
  • Insufficient contrast dose
• Poor initial opacification, which increases over time
  
  • Decreased renal blood flow (pre-existing hypotension, renal ischemia) or decreased urine outlflow (obstruction)
• No opacification
  
  • Avulsion of the kidney or occlusion of renal artery
  • Severe chronic hydronephrosis
  • Neoplasia
  • End-stage CKD

Pugh, C.R., Rhodes, W.H. & Biery, D.N. (1993) Contrast Studies of the Urogenital System. Veterinary Clinics of NA: Small Animal Practice 23, 281–306

Question 120

9 yr. MN dog presenting for multiple episodes of self-limiting, acute, caudal paresis.

• What’s your diagnosis?
• What are the imaging features that are characteristic of this case?
• Why is the clinical picture in this case different from how a cat might present?

Answer 120

• Aortic thromboembolism and ischemic myopathy
• MRI features:
  
  • Caudal aortic thrombus with visible collateral vessels
  • Streaky STIR hyperintensity in the muscles of the pelvic limb
  • Absent CE – especially pronounced because of surrounding muscle enhancement
• Dogs have better collateral circulation, which leads them to present with chronic paresis rather than the acute severe signs cats have

BROFMAN, P.J. & Thrall, D.E. (2006) MAGNETIC RESONANCE IMAGING FINDINGS IN A DOG WITH CAUDAL AORTIC THROMBOEMBOLISM AND ISCHEMIC MYOPATHY. Veterinary Radiology & Ultrasound 47, 334–338

Question 121

Regarding dual-phase CT of hepatic and splenic masses:

• What were the distinguishing features of malignant masses?
• What were the common imaging features of most of the hepatic masses in this study?
• Describe the typical features of splenic nodular hyperplasia, hematoma, and hemangiosarcoma

Answer 121

• No CT features were significantly associated with malignant masses
• What were the common imaging features of most of the hepatic masses in this study?
  
  • Heterogeneous compared to normal liver pre-C
  • Marked, generalized CE in early (portal) phase and delay phase
• Describe the typical features of splenic nodular hyperplasia, hematoma, and hemangiosarcoma
  
  • Most splenic masses were heterogeneous pre-C
  • NH + HSA: marked, generalized CE in early phase and delay phase
  • Hematoma: most had slight CE in early phase, and all had CE in delay phase

Jones, I.D., Lamb, C.R., Drees, R., et al. (2016) ASSOCIATIONS BETWEEN DUAL-PHASE COMPUTED TOMOGRAPHY FEATURES AND HISTOPATHOLOGIC DIAGNOSES IN 52 DOGS WITH HEPATIC OR SPLENIC MASSES. Veterinary Radiology & Ultrasound 57, 144–153

Question 122

• What are the most common ultrasonographic features of renal lymphoma in dogs?
• More commonly unilateral or bilateral?

Answer 122

• Pyelectasia
• Loss of CM distinction
• Renomegaly
• Renal deformity
• Hypoechoic lesions (masses, nodules, indistinct areas)
  
  • Hyperechoic lesions less common
• Most commonly bilateral

Taylor, A.J., Lara-Garcia, A. & Benigni, L. (2014) ULTRASONOGRAPHIC CHARACTERISTICS OF CANINE RENAL LYMPHOMA. Veterinary Radiology & Ultrasound 55, 441–446

Question 123

Regarding MRI of dogs with suspected DLSS in order to maximize foraminal narrowing?

• Which position and image acquisition plane maximized forminal narrowing?
• Which zone was narrowed most in each position?

Answer 123

• Neuroforaminal area was smallest in an oblique sagittal plane acquired perpendicular to the nerve root when the dog was in a hyperextended position
• Middle zone was smallest in both positions and imaging planes
  
  • ​Exit zone narrower than entry in hyperextension; larger in neutral

Zindl, C., Tucker, R.L., Jovanovik, J., et al. (2017) Effects of Image Plane, Patient Positioning, and Foraminal Zone on Magnetic Resonance Imaging Measurements of Canine Lumbosacral Intervertebral Foramina. Veterinary Radiology and Ultrasound 58, 206–215

Question 124

Regarding elastography of the metacarpal tendons in normal horses:

• How was intra- and inter-operator reproducibility?
• What was the normal appearance of the examined tendons and ligaments of the metacarpus?
• What was the effect of weight-bearing vs. non-weight bearing on tendon/ligament stiffness?

Answer 124

• How was intra- and inter-operator reproducibility?
  
  • Moderate to good
• What was the normal appearance of the examined tendons and ligaments of the metacarpus?
  
  • All similar, all mostly hard (blue/green), with soft surrounding tissue (yellow/red)
  • No significant difference between SDFT/DDFT – can be used as internal reference points for one another.
    
    • However, both appeared softer in a longitudinal plane.
  • Suspensory branches softer superficially (abaxially) than deep (abaxially)
• What was the effect of weight-bearing vs. non-weight bearing on tendon/ligament stiffness? No significant effect

Lustgarten, M., Redding, W.R., Labens, R., et al. (2014) ELASTOGRAPHIC CHARACTERISTICS OF THE METACARPAL TENDONS IN HORSES WITHOUT CLINICAL EVIDENCE OF TENDON INJURY. Veterinary Radiology & Ultrasound 55, 92–101

Question 125

Define: osteosclerosis, osteopetrosis, hyperostosis

Answer 125

• Osteopetrosis: bone disorder that causes increased bone density
  
  • Increased medullary opacity and endosteal cortical thickening
  • CAUSES diffuse osteosclerosis
• Osteosclerosis: the result of a condition that causes increased bone density WITHOUT change in size
• Hyperostosis: the result of a condition that causes increased bone density AND increased bone size

Fawcett, A., Malik, R., Rolfe Howlett, C., et al. (2014) Polyostotic hyperostosis in a domestic shorthair cat. Journal of Feline Medicine & Surgery 16, 432–440

Question 126

What is the prevalence of ectopic thyroid neoplasia in cats and where is it typically found?

Answer 126

Prevalence ~4%

Typically intra-thoracic (midline mediastinal) – >80%

Lingual ~10%

Question 127

Regarding MRI of vertebral endplate changes in dogs (Gendron, VRU 2012):

• What is the typical signalment of a dog with fatty endplate changes?
• What imaging feature(s) helped to differentiate disko and reactive endplate changes? What features were similar?
• What is the predilection site for reactive changes and why are these thought to occur?

Answer 127

• What is the typical signalment of a dog with fatty endplate changes? Small breed dogs
• What imaging feature(s) helped to differentiate disko and reactive endplate changes? What features were similar?
  
  • Paravertebral involvement = disko only
  • Reduced intervertebral disc space seen in both
• What is the predilection site for reactive changes and why are these thought to occur?
  
  • LS junction, likely secondary to disc injury/degeneration, which leads to increased loading and shearing forces on the endplates

GENDRON, K., DOHERR, M.G., Gavin, P., et al. (2012) MAGNETIC RESONANCE IMAGING CHARACTERIZATION OF VERTEBRAL ENDPLATE CHANGES IN THE DOG. Veterinary Radiology & Ultrasound 53, 50–56

Question 128

What is the relationship between renal cortical echogenicity and lipiduria?

Answer 128

Increasing cortical echogenicity is related to increased concentrations of urinary lipid

doi: 10.1111/vru.12100

Question 129

Comparison of fluoroscopy and CT for tracheal lumen diameter measurement and determination of stent size:

• How did measurements of tracheal height and width compare between fluoro and CT?
• (T/F): Although there was a difference between measurements based on fluoro and CT, there was no significant difference in stent choice.
• (T/F): Differences in measurements between fluoro and CT led to smaller stent sizes being selected based on CT measurements.
• (T/F): Intra- and inter-observer variability was higher with fluoro
• Was tracheal width or height used for selection of stent size?

Answer 129

• How did measurements of tracheal height and width compare between fluoro and CT?
  
  • Fluoro underestimated by 0.21 mm compared to CT
• (F): Although there was a difference between measurements based on fluoro and CT, there was no significant difference in stent choice.
  
  • Larger stents chosen based on CT
• (F): Differences in measurements between fluoro and CT led to smaller stent sizes being selected based on CT measurements.
• (T): Intra- and inter-observer variability was higher with fluoro
• Tracheal height was used for selection of stent size

Williams, J.M., Krebs, I.A., Riedesel, E.A., et al. (2016) COMPARISON OF FLUOROSCOPY AND COMPUTED TOMOGRAPHY FOR TRACHEAL LUMEN DIAMETER MEASUREMENT AND DETERMINATION OF INTRALUMINAL STENT SIZE IN HEALTHY DOGS. Veterinary Radiology & Ultrasound 57, 269–275

Question 130

Gender determination in lizards:

• Rank imaging methods by accuracy
• What were the imaging features that allowed sex determination?

Answer 130

• Rank imaging methods by accuracy
  
  • CT + contrast > RX + contrast >> US = CT without contrast
  • RX without contrast was a no-go
• What were the imaging features that allowed sex determination?
  
  • RX+C and CT+C: spindle-shaped, contrast-filled structures = hemipenes
  • CT: smegma was hyperattenuating and allowed recognition of the hemipenes in 2/9 males

Di Ianni, F., Volta, A., Pelizzone, I., et al. (2014) DIAGNOSTIC SENSITIVITY OF ULTRASOUND, RADIOGRAPHY AND COMPUTED TOMOGRAPHY FOR GENDER DETERMINATION IN FOUR SPECIES OF LIZARDS. Veterinary Radiology & Ultrasound 56, 40–45

Question 131

CATS:

• What is a normal T/S ratio?
• What is a normal percent dose uptake?

Answer 131

• What is a normal T/S ratio? 0.9 (up to 1.5)
• What is a normal percent dose uptake? 0.2% to 4% depending on the paper

Question 132

• (T/F): Dogs can develop bilateral pyelectasia when receiving IV saline (0.9%). This should never be unilateral.
• A pelvic width of _____ was seen in clinically normal patients that were not on fluids.
• What was the maximum pelvic width identified in a patient with pyelonephritis?
• What cut-off for pelvic width is 100% predictive of obstruction?

Answer 132

• (FALSE): Dogs can develop bilateral OR UNILATERAL pyelectasia when receiving IV saline (0.9%).
• A pelvic width of 3 mm was seen in clinically normal patients that were not on fluids.
• What was the maximum pelvic width identified in a patient with pyelonephritis? 12 mm
• What cut-off for pelvic width is 100% predictive of obstruction? 13 mm

D’Anjou, M.A., Bédard, A. & Dunn, M.E. (2011) Clinical Significance Of Renal Pelvic Dilatation On Ultrasound In Dogs And Cats. Veterinary Radiology and Ultrasound 52, 88–94

Question 133

What is the most likely diagnosis in these cats?

Answer 133

Multifocal disease, likely secondary to thyroid carcinoma

Peterson, M.E. & Broome, M.R. (2015) Thyroid scintigraphy findings in 2096 cats with hyperthyroidism. Veterinary Radiology and Ultrasound 56, 84–95

Question 134

Carotid body paragangliomas:

• Where do these occur and what type of receptor are they associated with?
• What is the most common presenting complaint?
• What is the typical signalment?

Answer 134

• Where do these occur and what type of receptor are they associated with?
  
  • Bifurcation of the common carotid
  • Chemoreceptors
• What is the most common presenting complaint?
  
  • Cervical mass, dyspnea
  • Less common: Horner’s, head tilt, facial nerve paralysis, dysphagia
• What is the typical signalment?
  
  • Older, MC, Boston

Mai, W., Seiler, G.S., Lindl-Bylicki, B.J., et al. (2015) CT AND MRI FEATURES OF CAROTID BODY PARAGANGLIOMAS IN 16 DOGS. Veterinary Radiology & Ultrasound 56, 374–383

Question 135

What are the ddx for increased bone density in cats?

Answer 135

• Osteopetrosis
• FeLV-induced diffuse osteosclerosis
• Hypertrophic osteopathy (paraneoplastic, infectious)
• Hypervitaminosis A
• Scottish Fold osteochondrodysplasia
• Polyostotic hyperostosis

Fawcett, A., Malik, R., Rolfe Howlett, C., et al. (2014) Polyostotic hyperostosis in a domestic shorthair cat. Journal of Feline Medicine & Surgery 16, 432–440

Question 136

Regarding outcome after transsphenoidal hypophysectomy for PDH:

• What significant factors were identified that were correlated with recurrence?
• What significant factors were identified that were correlated with decreased survival time?
• What ratio indicates pituitary enlargement?

Answer 136

• What significant factors were identified that were correlated with recurrence?
  
  • Higher pituitary height/brain area ratio (P/B ratio)
  • Increased UCCR
• What significant factors were identified that were correlated with decreased survival time?
  
  • Enlarged pituitary gland
• Enlarged: pituitary height to brain height ratio (P/B) > 0.31

van Rijn, S.J., Galac, S., Tryfonidou, M.A., et al. (2016) The Influence of Pituitary Size on Outcome After Transsphenoidal Hypophysectomy in a Large Cohort of Dogs with Pituitary-Dependent Hypercortisolism. Journal of veterinary internal medicine 30, 989–995

Question 137

Comparison of fluoroscopy and CT for tracheal lumen diameter measurement and determination of stent size:

• What is the typical sizing criteria for a tracheal stent?
• What type of force is applied by the stent to maintain lumen patency?
• What complications can be seen with inappropriate stent size?

Answer 137

• What is the typical sizing criteria for a tracheal stent?
  
  • Diameter 10-20% greater than the maximal tracheal diameter during maximal inflation
• What type of force is applied by the stent to maintain lumen patency?
  
  • Radial force applied to the tracheal wall
• What complications can be seen with inappropriate stent size?
  
  • Mucosal ischemia
  • Granuloma formation
  • Rupture
  • Migration

Williams, J.M., Krebs, I.A., Riedesel, E.A., et al. (2016) COMPARISON OF FLUOROSCOPY AND COMPUTED TOMOGRAPHY FOR TRACHEAL LUMEN DIAMETER MEASUREMENT AND DETERMINATION OF INTRALUMINAL STENT SIZE IN HEALTHY DOGS. Veterinary Radiology & Ultrasound 57, 269–275

Question 138

• What are the MRI characteristics of an intracranial abscess?
• What are the MRI features of parasitic meningoencephalitis?

Answer 138

• What are the MRI characteristics of an intracranial abscess?
  
  • T1 hypo, T2 hyper, strong peripheral CE
  • Perilesional edema
  • Meningeal CE
  • Ruptured abscess has resulted in failure of CSF suppression on FLAIR
• What are the MRI features of parasitic meningoencephalitis?
  
  • Focal or multifocal parenchymal lesions of variable SI
  • Parenchymal and meningeal CE
  • Intraparenchymal hemorrhage with migration

Hecht, S. & Adams, W.H. (2010) MRI of Brain Disease in Veterinary Patients Part 2: Acquired Brain Disorders. Veterinary Clinics of NA: Small Animal Practice 40, 39–63

Question 139

What are the suggested etiologies of muscularis layer thickening?

Zwingenberger, A.L., Marks, S.L., Baker, T.W., et al. (2010) Ultrasonographic Evaluation of the Muscularis Propria in Cats with Diffuse Small Intestinal Lymphoma or Inflammatory Bowel Disease. Journal of Veterinary Internal Medicine 24, 289–292

Answer 139

Muscular hypertrophy, muscular shortening, or infiltrative disease not identified on histopath (i.e. not biopsied at the same site as seen on US)

Question 140

• What is the most common radiographic pattern of NCPE?
• What findings were specifically noted for post-obstructive NCPE?
• Was there a lobe predilection?
• What features are predictive of survival?

Answer 140

• Most common: mixed pattern, bilateral and symmetrical, multifocal, peripheral and dorsal
• Post-obstructive: asymmetric, unilateral, dorsal distribution (did not reach significance)
• When unilateral, most often R caudal lung lobe
• No features differed between survivors and non-survivors

Bouyssou, S., Specchi, S., Desquilbet, L., et al. (2017) RADIOGRAPHIC APPEARANCE OF PRESUMED NONCARDIOGENIC PULMONARY EDEMA AND CORRELATION WITH THE UNDERLYING CAUSE IN DOGS AND CATS. Veterinary Radiology & Ultrasound 58, 259–265

Question 141

GI contrast study

• What is flocculation?
• What is segmentation?

Answer 141

• Flocculation = sedimentation and clumping
• Segmentation (see image) = separation and pooling

Gomez, J.A. (1974) The Gastrointestinal Contrast Study; methods and interpretation. Veterinary Clinics of NA: Small Animal Practice 4, 805–841

Question 142

• What are the sonographic features of FGESF?
• What is the prognosis with different treatment regimens?

Answer 142

• What are the sonographic features of FGESF?
  
  • Focal mass with loss of layering
  • Mixed echogenicity with hyperechoic regions (likely fibrosis)
  • Mild regional lymphadenopathy
• What is the prognosis with different treatment regimens?
  
  • Cats treated with abx or abx + surgery had a significantly shorter survival time than cats treated with steroid and surgery

Weissman, A., Penninck, D.G., Webster, C.R.L., et al. (2013) Ultrasonographic and clinicopathological features of feline gastrointestinal eosinophilic sclerosing fibroplasia in four cats. Journal of Feline Medicine & Surgery 1–7

Question 143

• (T/F): There is no association between left atrial enlargement and left mainstem bronchial collapse
• (T/F): The most common airways affected by bronchomalacia are in the left cranial, right middle, and right caudal lobes.

Answer 143

• (TRUE): There is no association between left atrial enlargement and left mainstem bronchial collapse
• (FALSE): The most common airways affected by bronchomalacia are in the left cranial, right middle, and LEFT caudal lobes.

Singh, M.K., Johnson, L.R., Kittleson, M.D., et al. (2012) Bronchomalacia in Dogs with Myxomatous Mitral Valve Degeneration. Journal of Veterinary Internal Medicine 26, 312–319

Question 144

• What is the most likely diagnosis in this cat?
• What are some causes of this condition?

Answer 144

• What is the most likely diagnosis in this cat? Esophageal stricture
• What are some causes of this condition? Doxycycline, GE reflux, foreign bodies, ingestion of caustic agents

​

Pollard, R.E. (2012) Imaging Evaluation of Dogs and Cats with Dysphagia. ISRN Veterinary Science 2012, 1–15

Question 145

Comparison of the radiographic and tracheoscopic appearance of the dorsal tracheal membrane in large and small breed dogs (Lindl-Bylicki, 2015):

• What is the suggested significance of near-complete radiographic opacification of the tracheal lumen by a DTM?
• Almost every dog in this study had dorsal opacification on rads. What was the breakdown of tracheoscopic findings? What is the significance of this finding?

Answer 145

• What is the suggested significance of near-complete radiographic opacification of the tracheal lumen by a DTM? Likely represents clinically significant TC
• Almost every dog in this study had dorsal opacification on rads. What was the breakdown of tracheoscopic findings? What is the significance of this finding?
  
  • About 20% of dogs (both large and small breed) had no invagination and no collapse on scope.
    
    • ​Thus dorsal opacification may not represent DTM?
  • About 35% of small dogs had TC (no large dogs)
  • Small proportion of dogs had invagination and no collapse

Lindl-Bylicki, B.J., Johnson, L.R. & Pollard, R.E. (2015) COMPARISON OF THE RADIOGRAPHIC AND TRACHEOSCOPIC APPEARANCE OF THE DORSAL TRACHEAL MEMBRANE IN LARGE AND SMALL BREED DOGS. Veterinary Radiology & Ultrasound 56, 602–608

Question 146

Describe the disease distribution in each cat

Answer 146

1. Unilateral
2. Bilateral asymmetric
3. Bilateral symmetric
4. Multifocal

Peterson, M.E. & Broome, M.R. (2015) Thyroid scintigraphy findings in 2096 cats with hyperthyroidism. Veterinary Radiology and Ultrasound 56, 84–95

Question 147

What is the order of enhancement of intra-ocular structures when assessed with CEUS?

How does CEUS compare to Doppler evaluation?

Answer 147

1. Retina, choroid, and retrobulbar structures
2. Iris and ciliary body
3. Optic nerve

Color Doppler signal intensity was much weaker, especially around the iris and ciliary body

Question 148

• What is the sentinel clot sign?
• What is the average HU of the sentinel clot vs. the remainder of the effusion?
• What is the CE pattern of the sentinel clot?

Answer 148

• The highest attenuating hematoma (sentinel clot; HU 45-70) is expected to be close to the site of bleeding. Lower attenuating unclotted blood (HU 20-45) is located farther from the source.
• Sentinel clot shouldn’t enhance. If there’s enhancement, that’s a sign of active bleeding.

Specchi, S., Auriemma, E., Morabito, S., et al. (2017) EVALUATION OF THE COMPUTED TOMOGRAPHIC “SENTINEL CLOT SIGN” TO IDENTIFY BLEEDING ABDOMINAL ORGANS IN DOGS WITH HEMOABDOMEN. Veterinary Radiology & Ultrasound 58, 18–22

Question 149

How might you distinguish pharyngeal weakness from cricopharyngeal dyssynchrony?

Answer 149

PCR will be similar (0.6) but the time to UES opening will be different.

Weakness will have normal time to opening (0.1 sec) and dyssynchrony will be delayed (0.3 sec)

Question 150

Carotid body paragangliomas:

• What is the typical CT and MRI appearance?

Answer 150

• CT:
  
  • ​Isodense to muscle often extends toward and sometimes invades through the base of the skull or bullae
  • Fleck of mineral
• MRI:
  
  • ​T2w AND T1 hyper to muscle, some T2*w hypo foci (hemorrhage)
  • Strongly, heterogeneously CE on both
  • Variable margination
  • Often entraps and completely compresses external carotid
  • Sometimes invades jugular, maxillary, and linguofacial veins
• Invasion of the basilar portion of the skull with widening of the petro-occipital fissure, bulla lysis, basisphenoid lysis
• Effacement of MRLN

Mai, W., Seiler, G.S., Lindl-Bylicki, B.J., et al. (2015) CT AND MRI FEATURES OF CAROTID BODY PARAGANGLIOMAS IN 16 DOGS. Veterinary Radiology & Ultrasound 56, 374–383

Question 151

What is the likely cause of this pattern of IRU?

Answer 151

Focal muscle uptake (and possible myonecrosis) after a peroneal nerve block.

Superimposed with tibial diaphysis on the lateral view, but slightly lateral to the tibia on the caudal view.

Griffin IV, J.F., Young, B.D., Fosgate, G.T., et al. (2010) FOCAL SKELETAL MUSCLE UPTAKE OF 99mTECHNETIUM-HYDROXYMETHYLENE Diphosphonate FOLLOWING PERONEAL NERVE BLOCKS IN HORSES. Veterinary Radiology & Ultrasound 51, 338–343

Question 152

Regarding intrathoracic histiocytic sarcoma:

• What are the most common radiographic findings?
• What are the most common CT findings?

Answer 152

​

• What are the most common radiographic findings?
  
  • RMLL mass in the periphery (commonly ventral)
  • Lymphadenopathy (sternal, TB >> cranial mediastinal)
  • Less common: pulmonary nodules, pleural effusion, interstitial or alveolar pulmonary pattern
• What are the most common CT findings?
  
  • Non-cavitated, mildly heterogeneously CE mass
  • Bronchocentric
  • Poorly marginated

TSAI, S., Sutherland-Smith, J., Burgess, K., et al. (2011) IMAGING CHARACTERISTICS OF INTRATHORACIC HISTIOCYTIC SARCOMA IN DOGS. Veterinary Radiology & Ultrasound 53, 21–27

Question 153

• What is the relationship between proximal suspensory desmitits and IRU in the proximopalmar/plantar aspect of MCIII/MTIII?
• What is the relationship of IRU in this region and lameness?
• T/F: the majority of horses with proximal suspensory desmitis appear normal on bone scan
• T/F: there was a significant correlation between IRU in this region in the hindlimbs and radiographic abnormalities.
• What is a differential for uptake in this region in the forelimb of a racehorse with acute, severe signs that are worse on hard ground?

Answer 153

• Forelimb: no significant association between IRU and SL desmitis
• Hindlimb: significant IRU with SL desmitis
• In all limbs, IRU was significantly associaed with lameness
• True: the majority of horses with proximal suspensory desmitis appear normal on bone scan
• False: no correlation with radiographic abnormalities
• DDX: stress fracture

Dyson, S.J., Weekes, J.S. & Murray, R.C. (2007) Scintigraphic evaluation of the proximal metacarpal and metatarsal regions of horses with proximal suspensory desmitis. Veterinary Radiology and Ultrasound 48, 78–85

Question 154

Regarding MRI of dogs with head trauma:

• What were the common intra-axial and extra-axial changes?
• Which sequence was best for evaluating extra-axial hemorrhage?

Answer 154

• Intra-axial:
  
  • Focal, T2w hyperintense gray matter lesions primarily in the rostral fossa (cortical contusions)
  • About half voided on T2* GRE
  • No CE
  • About 1/3 of dogs had midline shift +/- herniations
• Extra-axial:
  
  • Hemorrhage – subdural >> subarachnoid = epidural
    
    • Best seen on FLAIR
  • 50% had fractures of the cranial vault

Yanai, H., Tapia-Nieto, R. & Cherubini, G.B. (2015) Results of magnetic resonance imaging performed within 48 hours after head trauma in dogs and association with outcome: 18 cases (2007–2012). Journal of the American Veterinary Medical Association 246, 1222–1229

Question 155

Regarding neurological manifestations of FIP (Crawford, 2017 JVIM):

• What were the common MRI features of FIP?

Answer 155

• Ventriculomegaly (severity correlated to severity of clinical signs)
  
  • Compression of brainstem by dilated 4th ventricle
• Periventricular FLAIR hyperintensity
• Meningeal and ependymal CE
• Transtentorial or foramen magnum herniation
• Incomplete CSF suppression on FLAIR (less common)
• Syringomyelia

Crawford, A.H., Stoll, A.L., Sanchez-Masian, D., et al. (2017) Clinicopathologic Features and Magnetic Resonance Imaging Findings in 24 Cats With Histopathologically Confirmed Neurologic Feline Infectious Peritonitis. Journal of Veterinary Internal Medicine 31, 1477–1486

Question 156

• What are the MRI features of hepatocellular carcinoma when imaged using gadoxetate?
• What is the significance of the reported signal intensity ratio?
• What is the time to maximum contrast enhancement of the liver?

Answer 156

• Hypointense on T1w GRE pre- and post-contrast images (much more hypointense post)
  
  • Heterogeneity correlated with increasing grade (hemorrhage or necrosis)
• Signal intensity values <1 – implies impaired but persistent hepatocyte function
• Max hepatic CE (and therefore delineation of the mass) ~ 10 min

Constant, C., Hecht, S., Craig, L.E., et al. (2016) GADOXETATE DISODIUM (GD-EOB-DTPA) CONTRAST ENHANCED MAGNETIC RESONANCE IMAGING CHARACTERISTICS OF HEPATOCELLULAR CARCINOMA IN DOGS. Veterinary Radiology & Ultrasound 57, 594–600

Question 157

What was the relationship of adrenal contrast enhancement pattern of dogs with PDH and their biochemical paramenters?

Answer 157

The disorderly CE pattern was more pronounced in dogs with higher cortisol levels (> 24 ug/dl)

Bargellini, P., Orlandi, R., Paloni, C., et al. (2013) CONTRAST-ENHANCED ULTRASONOGRAPHIC CHARACTERISTICS OF ADRENAL GLANDS IN DOGS WITH PITUITARY-DEPENDENT HYPERADRENOCORTICISM. Veterinary Radiology & Ultrasound 54, 283–292

Question 158

Regarding dual-phase CT of hepatic and splenic masses:

• What were the distinguishing features of malignant masses?
• What were the common imaging features of most of the hepatic masses in this study?
• Describe the typical features of splenic nodular hyperplasia, hematoma, and hemangiosarcoma

Answer 158

• No CT features were significantly associated with malignant masses
• What were the common imaging features of most of the hepatic masses in this study?
  
  • Heterogeneous compared to normal liver pre-C
  • Marked, generalized CE in early (portal) phase and delay phase
• Describe the typical features of splenic nodular hyperplasia, hematoma, and hemangiosarcoma
  
  • Most splenic masses were heterogeneous pre-C
  • NH + HSA: marked, generalized CE in early phase and delay phase
  • Hematoma: most had slight CE in early phase, and all had CE in delay phase

Jones, I.D., Lamb, C.R., Drees, R., et al. (2016) ASSOCIATIONS BETWEEN DUAL-PHASE COMPUTED TOMOGRAPHY FEATURES AND HISTOPATHOLOGIC DIAGNOSES IN 52 DOGS WITH HEPATIC OR SPLENIC MASSES. Veterinary Radiology & Ultrasound 57, 144–153

Question 159

How does acepromazine influence scintigraphic count density in horse limbs?

Answer 159

Intravenous administration of acepromazine increases peripheral blood flow causing an earlier onset of the vascular phase during the three-phase bone scan; increased count density of vascular phase

Acepromazine did not increase the count density of the bone phase scintigrams

Solano, M., Welcome, J. & Johnson, K. (2005) EFFECTS OF ACEPROMAZINE ON THREE-PHASE 99mTc-MDP BONE IMAGING IN 11 HORSES. Veterinary Radiology & Ultrasound 46, 437–442

Question 160

Comparing horizontal beam vs. conventional vertical beam radiography (Lynch, 2012 VRU):

• Which view(s) were best for detecting and grading the severity of pneumothorax?
• Which view(s) had the lowest sensitivity for detection of pneumothorax?
• Which view(s) had the lowest sensitivity for grading pneumothorax and pleural effusion?
• Which view(s) were best for detecting and grading pleural effusion?

Answer 160

• Which views were best for detecting and grading the severity of pneumothorax?
  
  • HB both laterals and VB left lateral
  • Of these, the right lateral HB was best
• Which view(s) had the lowest sensitivity for detection of pneumothorax?
  
  • VB VD and DV views
• Which view(s) had the lowest sensitivity for grading pneumothorax and pleural effusion?
  
  • VB VD and DV views
• Which view(s) were best for detecting and grading pleural effusion?
  
  • No significant difference between views, however the HB left lateral view had the highest rate detection and severity grade

LYNCH, K.C., Oliveira, C.R., MATHESON, J.S., et al. (2011) DETECTION OF PNEUMOTHORAX AND PLEURAL EFFUSION WITH HORIZONTAL BEAM RADIOGRAPHY. Veterinary Radiology & Ultrasound 53, 38–43

Question 161

• What are the most common imaging findings in dysphagic cats undergoing video fluoroscopy?
• What causes of dysphagia were not identified in the Levine, 2014 study?
• How did the measurements (PCR, UES opening, etc.) for cats compare to dogs?

Answer 161

• Most common findings:
  
  • Hiatal hernia
  • Esophageal stricture
  • Esophageal dysmotility (higher percentage of swallows from which no primary peristaltic waves are generated)
• No cases of oropharyngeal or cricopharyngeal dysphagia
• Cats = dogs (for once)

Levine, J.S., Pollard, R.E. & Marks, S.L. (2014) Contrast videofluoroscopic assessment of dysphagic cats. Veterinary Radiology and Ultrasound 55, 465–471

Question 162

What are the MRI features of thiamine deficiency?

Answer 162

Bilaterally symmetrical T2w-hyperintensities of the lateral geniculate nuclei, caudal colliculi, facial nuclei, medial vestibular nuclei, red nuclei, and cerebellar nodulus

LG CC F MV R CN

LarGe Crunchy Cats Forcibly Meowing Very Rudely. CAT NO!

Question 163

According to a 2014 study, what is the prevalence of incidental thyroid nodules in hypercalcemic dogs undergoing cervical ultra- sound (excluding dogs with palpable cervical masses)?

What percenrage of these were malignant?

Answer 163

Prevalence: 15% of dogs had at least one thyroid nodule

Of these nodules, 22% were malignant (adenocarcinoma)

Pollard, R.E., Bohannon, L.K. & Feldman, E.C. (2014) PREVALENCE OF INCIDENTAL THYROID NODULES IN ULTRASOUND STUDIES OF DOGS WITH HYPERCALCEMIA (2008-2013). Veterinary Radiology & Ultrasound 56, 63–67

Question 164

What are the standard views for evaluation of the foot in cows?

Answer 164

• Dorsal 65 proximal-palmarodistal and a lateral 30 dorsal-mediodistal oblique
• Allow the pedal bone and distal sesamoid bone, as well as the distal interphalangeal joint, to be displayed and evaluated in 2 different planes

DOI: https://doi.org/10.1016/j.cvfa.2013.11.003

Question 165

• What dose of contrast/gas/whatever will eliminate bladder wall irregularity that is due to lack of distension?
• What are the differentials for attached filling defects in the urinary bladder? Detached?

Answer 165

• What dose of contrast/gas/whatever will eliminate bladder wall irregularity that is due to lack of distension? 4 ml/kg
• What are the differentials for attached filling defects in the urinary bladder? Detached?
  
  • Attached: clots, neoplasia, polyp, hematoma, ureterocele
  • Detached: calculi, clots, gas bubbles

Pugh, C.R., Rhodes, W.H. & Biery, D.N. (1993) Contrast Studies of the Urogenital System. Veterinary Clinics of NA: Small Animal Practice 23, 281–306

Question 166

Non-infectious inflammatory brain disease in dogs:

• What are some key features of NLE?
• Characteristics of NME?
• What are the three forms of GME?

Answer 166

• NLE vs. other:
  
  • Cerebral white matter
  • Brainstem involvement +/- cerebellum
  • Yorkies
• NME:
  
  • Pugs, Maltese, Shih Tzus, Lhasa apsos, Chihuahuas
  • Gray-white matter junction resulting in loss of distinction between the two
  • Almost always limited to cerebral hemispheres
• GME: ocular, focal, or disseminated forms
  
  • White matter over gray matter but no specific topography
  • Non-necrotizing

Higginbotham, M.J., Kent, M. & Glass, E.N. (2007) Noninfectious Inflammatory Central Nervous System Diseases in Dogs. Continuing Education Compendium 1–11

Question 167

MRI metallic artifacts associated with surgical implants and foreign material:

• Which types of metal resulted in the largest susceptibiltiy artifact?
• What are the three typical feautures of metallic artifacts?

Answer 167

• Which types of metal resulted in the largest susceptibiltiy artifact?
  
  • Steel > surgical stainless steel, titanium, and lead
• What are the three typical feautures of metallic artifacts?
  
  • Geometric distortion
  • Central area of signal loss
  • Peripheral, linear, sharply demarcated hyperintense signal

Sutherland-Smith, J. & Tilley, B. (2012) MAGNETIC RESONANCE IMAGING METALLIC ARTIFACT OF COMMONLY ENCOUNTERED SURGICAL IMPLANTS AND FOREIGN MATERIAL. Veterinary Radiology & Ultrasound 53, 312–317

Question 168

How do you distinguish ureters from ductus deferens, ampullae and seminal vesicles?

What is the normal appearance of the UVJs?

Answer 168

• Peristaltic movements of the ureters can be used for ID of this structure.
• Ductus deferens is seen dorsomedial to the ureters.
• Ampullae are very round and hyperechoic, dorsolateral to ureters.
• Seminal vesicles are fluid-filled and dorsal to the urethra.

The UVJs are seen as somewhat flattened, oval-shaped structures on the dorsal surface of the bladder.

doi: 10.1111/j.1740-8261.2007.00297.x

Question 169

• Does head and neck position have an effect on nasopharyngeal size in horses? If so, which results in the smallest diameter?

Answer 169

• Significant influence of head and neck position on pharyngeal diameter, with head position having the major effect; neck position was less important, but still significant
• Smallest pharyngeal diameter was found at the dorsal, flexed position
• Largest diameter at mid-level, extended
• At every level, flexion narrowed and extension embiggened

CEHAK, A., ROHN, K., BARTON, A.-K., et al. (2010) EFFECT OF HEAD AND NECK POSITION ON PHARYNGEAL DIAMETER IN HORSES. Veterinary Radiology & Ultrasound 51, 491–497

Question 170

• What are the common MRI features of discospondylitis?
• What site is most commonly affected?
• What site is uncommonly affected (or not at all)?

Answer 170

• Vertebral endplate changes at apposed vertebrae
  
  • T2w/T1w hypointense, STIR hyperintense
  • Erosion
• Intervertebral disc changes:
  
  • T2w/STIR hyperintense
  • Distorted shape/narrowed, some protruding/extruding
• Contrast enhancement of the vertebral endplates, intervertebral discs and paravertebral soft tissues
• Epidural extension of proliferative/inflammatory tissue
• Focal > multifocal
  
  • L7-S1 most common
  • No cervical lesions in this study
• Subluxation uncommon

Carrera, I., Sullivan, M., MCCONNELL, F., et al. (2011) MAGNETIC RESONANCE IMAGING FEATURES OF DISCOSPONDYLITIS IN DOGS. Veterinary Radiology & Ultrasound 52, 125–131

Question 171

Diagnosis?

Answer 171

Portocaval shunt

Question 172

• Why does this artifact occur?
• In which sequences is this artifact typically seen?
• Which sequence is less susceptible?

Answer 172

• Why does this artifact occur?
  
  • Magic angle is the condition in which the dipolar interaction between two nuclei becomes zero; this occurs at an angle of 55* to the main magnetic field
• In which sequences is this artifact typically seen?
  
  • T1, PD, GRE
  • Low TE (<30ms) and high flip angle increase this effect
• Which sequence is less susceptible? T2 (longer TE)

Busoni, V. & Snaps, F. (2002) EFFECT OF DEEP DIGITAL FLEXOR TENDON ORIENTATION ON MAGNETIC RESONANCE IMAGING SIGNAL INTENSITY IN ISOLATED EQUINE LIMBS—THE MAGIC ANGLE EFFECT. Veterinary Radiology & Ultrasound 43, 428–430

Question 173

• What angiographic imaging technique is displayed in this image?
• What is the cause of the low signal intensity labeled with an *?

Answer 173

Bright blood angiography.

Low signal intensity is due to turbulence of the blood flowing through the PDA into the PA

Lee, Y., Jung, J., Park, J., et al. (2017) CARDIAC MAGNETIC RESONANCE IMAGING OF PATENT DUCTUS ARTERIOSUS IN THREE DOGS. Veterinary Radiology & Ultrasound 58, 62–75

Question 174

• Name the origin and insertion of the iliopsoas muscle.
• Which parts of this muscle is consistently difficult to image on US?
• What is the US appearance at the insertion of the iliopsoas?
• What are the clinical signs of injury to the iliopsoas?

Answer 174

• Origin: transverse processes of L2 and L3
• Insertion: lesser trochanter of the femur
  
  • Triangular/linear, hyperechoic tendinous insertion
• The origin at L2 and the origin of the iliacus portion of the muscle were consistently difficult to image.
• What are the clinical signs of injury to the iliopsoas?
  
  • Pain upon extension and internal rotation of the hip

Cannon, M.S. & Puchalski, S.M. (2008) ULTRASONOGRAPHIC EVALUATION OF NORMAL CANINE ILIOPSOAS MUSCLE. Veterinary Radiology & Ultrasound 49, 378–382

Question 175

Stent placement for palliation of mass-associated chylothorax:

• What type of stent was used and where was it placed?
• What complications were noted?

Answer 175

Self-expanding endovascular stents in the cranial vena cava and pulmonary artery. Chylothorax resolved after surgery with post-op survival times of >6 months.

Complications: periprocedural arrhythmia and eventual obstruction of the stent with tumor extension in 1 dog (the other died of GDV)

Taylor, S., Rozanski, E.A., Sato, A.F., et al. (2017) Vascular stent placement for palliation of mass-associated chylothorax in two dogs. Journal of the American Veterinary Medical Association 251, 696–701

Question 176

Muscularis layer thickening is associated with infiltrative disease in what layer(s) of the small bowel in cats? What about lymphadenopathy?

Answer 176

Muscularis thickening is associated with disease in the mucosa and submucosa

Lymphadenopathy is associated with disease in the mucosa and submucosa +/- muscularis

Zwingenberger, A.L., Marks, S.L., Baker, T.W., et al. (2010) Ultrasonographic Evaluation of the Muscularis Propria in Cats with Diffuse Small Intestinal Lymphoma or Inflammatory Bowel Disease. Journal of Veterinary Internal Medicine 24, 289–292

Question 177

Regarding neurological manifestations of FIP (Crawford, 2017 JVIM):

• What are the three clinical neurological syndromes that were identified?
• Describe the pathophysiology of these neurological syndromes.
• What was the prognosis?

Answer 177

• What are the three clinical neurological syndromes that were identified?
  
  • Multifocal CNS > central vestibular > T3-L3 myelopathy
• Describe the pathophysiology of these neurological syndromes.
  
  • Pyogranulomatous vasculitis, primarily affecting leptomeninges, ependyma and choroid plexus
• What was the prognosis?
  
  • Terrible. All cats euthanized within 2 weeks.

Question 178

• Normal values for swallow studies are measured from what time point?
• What is considered normal for each of the following:
  
  • UES opening
  • UES closing
  • Epiglottic reopening
  • Maximal pharyngeal contraction
• Is there a significant difference between liquid and kibble in terms of timing?

Answer 178

• Normal values for swallow studies are measured from what time point? Closure of the epiglottis
• What is considered normal for each of the following:
  
  • UES opening: 0.1 sec
  • UES closing: 0.25 sec
  • Epiglottic reopening: 0.3 sec
  • Maximal pharyngeal contraction: 0.15 sec
• There is a significant difference between liquid and kibble, but the numbers are so close to these numbers that there’s no way I’m memorizing both!

Pollard, R.E. (2012) Imaging Evaluation of Dogs and Cats with Dysphagia. ISRN Veterinary Science 2012, 1–15

Question 179

• Which of the feline joints are most likely to have cartilage damage without radiographic evidence of DJD?
• What are the most common radiographic signs of feline DJD?

Answer 179

• In order of prevalence:
  
  • Stifle
  • Coxofemoral joint
  • Elbow
  • Tarsus
• Common signs of DJD:
  
  • Joint associated mineralizations in the elbow
  • Dorsal bone proliferation at the tarometatarsal joint
  • Intra-articular mineral in the stifle (medial compartment)
  • Osteophytes of the coxofemoral joint
  • NO effusion or subchondral bone erosions

Freire, M., ROBERTSON, I.A.N., BONDELL, H.D., et al. (2011) RADIOGRAPHIC EVALUATION OF FELINE APPENDICULAR DEGENERATIVE JOINT DISEASE VS. MACROSCOPIC APPEARANCE OF ARTICULAR CARTILAGE. Veterinary Radiology & Ultrasound 52, 239–247

Question 180

• In a study of dogs with MUE, what imaging and/or clinical findings were significantly associated with survival/prognosis?
• What is considered a clinically significant midline shift in humans with TBI?

Answer 180

• Increased age and TNCC were significantly associated with poorer prognosis
• Midline shift, CSF total protein, and weight were not significant
• Humans with TBI: midline shift >0.5 is clinically significant
  
  • None of the patients in this study had shift >0.3 mm

Oliphant, B.J., Barnes Heller, H.L. & White, J.M. (2017) Retrospective Study Evaluating Associations Between Midline Brain Shift on Magnetic Resonance Imaging and Survival in Dogs Diagnosed With Meningoencephalitis of Unknown Etiology. Veterinary Radiology and Ultrasound 58, 38–43

Question 181

Which cranial nerve(s) contribute to the esophageal phase of swallowing?

Answer 181

CN 10

Question 182

Name the indicated structures in this equine carpus.

Answer 182

1. Medial palmar intercarpal
2. Lateral palmar intercarpal
3. Radiocarpal ligament
4. Lateral collateral branch
5. Transverse intercarpal ligaments
6. Palmar carpometacarpal ligaments

Gray, S.N., Puchalski, S.M. & Galuppo, L.D. (2013) COMPUTED TOMOGRAPHIC ARTHROGRAPHY OF THE INTERCARPAL LIGAMENTS OF THE EQUINE CARPUS. Veterinary Radiology & Ultrasound 54, 245–252

Question 183

Name the arterial branches shown by selective angiography of the ____ artery (level of L2).

Answer 183

Question 184

Name the labeled structures (at the level of the distal talus)

Answer 184

1. SDFT
2. Lateral DFT
3. Medial DFT
4. Metatarsocalcaneal ligament
5. Accessory ligament of the suspensory ligament
6. Long plantar ligament
7. Vessel
8. Interosseous ligament between the third tarsal bone and MtIV

Arrows point toward the accessory ligament of the DDFT (ALDDFT)

Dyson, S., Blunden, A. & Murray, R. (2017) Magnetic Resonance Imaging, Gross Postmortem, and Histological Findings for Soft Tissues of the Plantar Aspect of the Tarsus and Proximal Metatarsal Region in Non-Lame Horses. Veterinary Radiology and Ultrasound 58, 216–227

Question 185

Diagnosis?

Answer 185

MAPSS

Question 186

Regarding basihyoid ectopic thyroid carcinoma:

• What was the typical presenting complaint?
• In the patient that underwent thyroid scintigraphy, what findings were described?
• What were the common CT features?
• What are the main ddx for a mass in the region of the hyoid apparatus?

Answer 186

• What was the typical presenting complaint?
  
  • Ventral laryngeal mass, most often asymptomatic
• In the patient that underwent thyroid scintigraphy, what findings were described?
  
  • Normal thyroids and vague IRU in the region of the larynx
  • Not helpful for diagnosis
• What were the common CT features?
  
  • ALL lesions were ventral to the larynx, osteolytic, centered on the basihyoid bone, and had infiltration of the laryngeal wall
    
    • Fewer protruded into the lumen
  • Ovoid, symmetrical, well-defined margins (ventrally)
  • Highly vascularized capsule with hypoattenuating central areas (colloid)
  • Vascular invasion (lingual vein)
  • MRLNpathy - 3/5 metastatic
  • Foci of mineralization
  • Two normal thyroid glands are identifiable
• What are the main ddx for a mass in the region of the hyoid apparatus?
  
  • Soft tissue sarcoma
  • Primary bone tumor
  • Primary laryngeal carcinoma

Rossi, F., Caleri, E., Bacci, B., et al. (2013) COMPUTED TOMOGRAPHIC FEATURES OF BASIHYOID ECTOPIC THYROID CARCINOMA IN DOGS. Veterinary Radiology & Ultrasound 54, 575–581

Question 187

Canine digital tumors:

• Which was most common? What radiographic features are noteworthy?
• What factors had a positive impact on survival time?
• What factors were related to a decreased survival time?
• What factors were related to a shorter local disease-free or metastasis-free interval?

Answer 187

• Which was most common? What radiographic features are noteworthy?
  
  • SCC most common
  • Often lytic, may affect multiple digits (either at the time of presentation or later)
• What factors had a positive impact on survival time?
  
  • Surgical intervention
• What factors were related to a decreased survival time? None!
• What factors were related to a shorter local disease-free or metastasis-free interval? Stage of tumor

Henry, C.J. & Brewer, W.G. (2005) Canine Digital Tumors: A Veterinary Cooperative Oncology Group Retrospective Study of 64 Dogs. Journal of Veterinary Internal Medicine 19, 720–724

Question 188

Spinal Neoplasms

• Extradural ddx
• Intradural-extramedullary ddx
• Intramedullary ddx

Answer 188

• Extradural ddx:
  
  • Bone tumors (OSA, FSA, CSA)
  • Metastatic carcinoma
  • Hemangiosarcoma
  • LSA
  • Multiple myeloma
• Intradural-extramedullary ddx
  
  • Meningioma
  • PNST (can also be intramedullary and extradural)
  • LSA
  • Neuroepithelioma (neuroblastoma)
• Intramedullary ddx
  
  • Glial cell tumors
  • Ependymoma
  • Metastatic (HSA, TCC, other)

Bagley, R.S. (2010) Spinal Neoplasms in Small Animals. Veterinary Clinics of NA: Small Animal Practice 40, 915–927

Question 189

• T/F: A mean ratio kidney to L2 length of >3.5 was found only in mesaticephalic dogs on the ventrodorsal view
• How did the mean ratio of kidney length to L2 length correlate with body weight?

Answer 189

• True
• Smaller dog, bigger ratio

Lobacz, M.A., Sullivan, M., Mellor, D., et al. (2012) EFFECT OF BREED, AGE, WEIGHT AND GENDER ON RADIOGRAPHIC RENAL SIZE IN THE DOG. Veterinary Radiology & Ultrasound 53, 437–441

Question 190

• What are the radiographic features of canine influenza virus?

Answer 190

• Mixed pulmonary patterns (mostly unstructured interstitial and alveolar)
• Cranioventral distribution > diffuse = caudodorsal
• Mild pleural effusion in 1/6 dogs
• No lymphadenopathy or mediastinal changes

Secrest, S.A. & Sharma, A. (2016) THORACIC RADIOGRAPHIC CHARACTERISTICS OF CANINE INFLUENZA VIRUS IN SIX DOGS. Veterinary Radiology & Ultrasound 57, 462–466

Question 191

Equine hoof wall radiography:

• What are the histological layers of the hoof wall from superficial to deep?
• Which layer(s) make up the bulk of the dorsal hoof wall and how much of the total hoof wall thickness does this represent?

Answer 191

• What are the histological layers of the hoof wall from superficial to deep?
  
  • Stratum externum, stratum medium, stratum internum, dermis parietis
• Which layer(s) make up the bulk of the dorsal hoof wall and how much of the total hoof wall thickness does this represent?
  
  • Stratum externum + medium = 65% of total dorsal hoof wall

Goulet, C., Olive, J., Rossier, Y., et al. (2015) Radiographic and anatomic characteristics of dorsal hoof wall layers in nonlaminitic horses. Veterinary Radiology and Ultrasound 56, 589–594

Question 192

Regarding porto-azygous shunts in dogs:

• Where did these shunts typically insert?
• From which portal tributary(ies) did these shunts originate?
• Where was maximal shunt diameter?
• What additional anomalous vasculature was identified in these dogs?

Answer 192

• Where did these shunts typically insert?
  
  • Insert into the azygous vein in the thorax (T8-T13)
  • A small number had a left-sided shunt until its insertion in the azygous
• From which portal tributaries did these shunts originate?
  
  • 90% originate from left gastric vein
  • Others from right gastric vein, some with caudal splenic loop
• Where was maximal shunt diameter?
  
  • Abdomen
• What additional anomalous vasculature was identified in these dogs?
  
  • Azygous continuation of the CVC

Or, M., Ishigaki, K., de Rooster, H., et al. (2016) Determination of Porto-Azygos Shunt Anatomy in Dogs by Computed Tomography Angiography. Veterinary Surgery 45, 1005–1012

Question 193

What are the normal US measurements of thickness for the following:

• Esophageal wall
• Cardia wall
• Pyloric wall
• Muscularis layer of the pylorus
• Length of the proximal duodenal submucosal thickening

Answer 193

• Esophageal wall: 5 mm
• Cardia wall: 5 mm
• Pyloric wall: 4.4 mm
• Muscularis layer of the pylorus: 2.5 mm
• Length of the proximal duodenal submucosal thickening: 4.7 mm

Couturier, L., Rault, D., Gatel, L., et al. (2012) ULTRASONOGRAPHIC CHARACTERIZATION OF THE FELINE CARDIA AND PYLORUS IN 34 HEALTHY CATS AND THREE ABNORMAL CATS. Veterinary Radiology & Ultrasound 53, 342–347

Question 194

Interpretation of an upper GI contrast study in dogs/cats:

• What appearance is expected for:
  
  • Inflammatory disease
  • Malabsorption
  • Mechanical ileus
  • Functional ileus
  • Masses

Answer 194

• Inflammatory disease
  
  • Normal to rapid GET and SITT
  • Flocculation, ulceration, ill-defined & smudged appearance
• Malabsorption
  
  • Usually normal, but anywhere from delayed to rapid GET and SITT
  • Functional ileus, flocculation, segmentation, fragmentation
• Mechanical ileus
  
  • Delayed gastric and/or SITT +/- complete stasis
  • Distension of GIT, dilution of contrast if marked fluid distension
  • Intussussception: thin rim of contrast around a tubular filling defect
• Functional ileus
  
  • Delayed transport with patent lumen
  • Mild distension
• Masses
  
  • Intra-luminal = filling defects
  • Mural = luminal narrowing, wall thickening, wall rigidity
  • Serosal = displacement of bowel without luminal change

Gomez, J.A. (1974) The Gastrointestinal Contrast Study; methods and interpretation. Veterinary Clinics of NA: Small Animal Practice 4, 805–841