VRU 2016 Flashcards
94% of lesions overlying a vertebral body are more likely to be diagnosed as what?
A) Ischemic myelopathy
B) Acute non-compressive nucleus pulpous extrusion (ANNPE)
Answer = A
What characteristics of a spinal cord lesion are more seen in ischemic myelopathy injuries?
A) Overlying a vertebral body
B) Lateralized intramedullary lesion
C) Larger lesion length
D) associated extradural material or extradural changes
E) A and C
F) B and D
G) A,B,C
H) B,C,D
Answer = E
More likely to be ischemic myelopathy (e.g. FCE) = overlying vertebral body, NO lateralization, & larger lesion length
More likely to be ANNPE = focal intramedullary T2 hyperintensity over IV disc space, lateralized lesion, reduced volume of IV disc, narrowed disc space, extradural material or extradural changes
Following dexmedetomidine administration, which of the following is seen on thoracic radiography and echocardiography?
A) Fractional shortening increased
B) False positive mitral & pulmonic valve regurgitation
C) Increased VHS and cardiac size on lateral & VD views
D) B and C
E) All the above
Answer = D
Following dexmed administration:
- Increased VHS and cardiac size on rads
- E point to septal separation & LV internal diameter in both systole/diastole increased
- Fractional shortening decreased
- Mitral & pulmonic regurgitation seen
Dexmed may cause false positive valve regurgitation & cardiomegaly
T or F, the number of tracheal bends in whooping cranes is NOT associated with age?
False.
# of tracheal bends is age-related, but NOT sex-related
A 3 yo dog with a palpable neck mass presents with lethargy, fever, neck pain, and bloodwork shows leukocytosis and neutrophilia. A cervical MRI shows very enlarged medial retropharyngeal lymph nodes. The most likely DDX is?
A) Metastatic thyroid carcinoma
B) Reactive granulomatous disease
C) Suppurative lymphadenitis
D) there is not information to tell, must aspirate.
Answer = C
Inflammatory lymphadenitis more likely in younger patients & present with LETHARGY, leukocytosis/neutrophilia (100% PPV), pyrexia (100% PPV), pain
Neoplastic cervical masses on MRI have greater ______ and ______ than inflammatory masses or inflammatory lymphadenitis.
Greater height and width
Which of the following accurately describes the expected lesions seen in tick-borne meningoencephalomyelitis?
A) Multifocal diffuse T2 grey matter hyper intensities of the midbrain, perilesional edema & meningeal enhancement
B) Bilateral symmetric, non-enhancing grey matter T2 hyper intensities of thalamus, hippocampus, and spinal cord without meningeal enhancement
C) Bilateral symmetric T2 hyperintensities of the lentiform nuclei
D) Bilateral, asymmetric periventricular T1 white matter hyperintensities
Answer = B
Tick-borne meningoencephalomyelitis is caused by a Flavivirus
MRI findings = bilateral, symmetrical GREY matter T2/FLAIR hyperintensities (to white matter), T1 iso/hypo, NON-enhancing lesions involving thalamus, hippocampus, brainstem, basal nuclei, cerebellum, & ventral horn of spinal cord with minimal to no mass effect,meningeal enhancement or perilesional edema
Smaller optic nerve sheath diameters are found in (young or adult) horses? and normal foal measurement is ____?
A) Adults, < 6.5mm
B) Foals, < 6.5mm
C) Foals, < 5mm
D) Adults, < 5mm
Answer = C
T or F, optic nerve sheath diameter varies with age.
FALSE.
No significant difference in optic nerve sheath diameter with weight or age
Which of the following is FALSE regarding U/S findings in horses with multicentric lymphoma?
A) Mediastinal and tracheobronchial lymphadenopathy is common
B) Abdominal lesions include hypoechoic hepatic & splenic nodules
C) Pleural & peritoneal effusion are seen in all horses
D) Alimentary lymphoma is more common in Standardbreds
Answer = C
PLeural effusion is seen in 31% but no reports of peritoneal effusion
U/S findings with multicentric lymphoma = multifocal lymphadenopathy (62%) - caudal deep cervical (at thoracic inlet), intrathoracic, intraabdominal (medial iliac/cecal), peritoneal effusion (46%), splenomegaly with hypoechoic nodules (46%), hepatomegaly with hypoechoic nodules (38%), focal small/large GI hypoechoic thickening (15%), pleural effusion (31%), pulmonary parenchymal changes (23%)
Describe the MRI imaging findings that may be seen in horses with trigeminal neuritis?
T1/T2 hypointense thickening with heterogeneous peripheral enhancement
DDx = PNST
Which is the most appropriate window setting for viewing nasal conchae on CT?
A) Narrow window width, ST reconstruction
B) Wide window width, ST reconstruction
C) Narrow window width, Bone/lung reconstruction
D) Wide window width, Bone/lung reconstruction
Answer = A
- conchae are inconspicuous when using a wide window, the conchae are visualized clearly when using a narrower window
- conchae are only faintly visible in CT images obtained with a wide window because they are so thin
- When intranasal air is replaced by exudate or tissue, the nasal epithelium/air interface is obliterated, but intact conchae will remain faintly visible & better with a narrow window (e.g. soft tissue) versus a wide window (e.g. lung or bone)
What is the major determinant of contrast enhancement in feline nasopharyngeal polyps?
inflammation is the major determinant of contrast medium accumulation in feline nasopharyngeal polyps, and the tendency for inflammation to affect predominantly the superficial stroma explains the frequent observation of a rim in postcontrast CT images. Conversely, more marked edema in the superficial stroma of polyps will tend to diminish the appearance of a rim in postcontrast CT images
Which of the following combination of factors will artifactually increase tympanic bulla thickness on CT?
A) Thin slices, narrow window, high frequency reconstruction
B) Thin slices, wide window, low frequency reconstruction
C) Thick slices, narrow window, low frequency reconstruction
D) Thick slices, wide window, high frequency reconstruction
Answer = C
Thick slices, low frequency reconstruction algorithm, & narrow window settings (which are necessary for ST evaluation) cause an increase in tympanic bulla thickness
T or F, wide window settings on CT enhance visibility of noise?
FALSE, wide window setting suppress visibility of noise
On CT, structures such as bone, nasal turbinates, and lungs have _______ inherent object contrast and should be viewed with _____ window settings.
Wide; wide
Which of the following most accurately describes the CT appearance of tympanic canal/bullae in brachycephalic dogs?
A) Large luminal volume & caudoventral thickening compared to non-brachycephalics
B) Smaller luminal volume & rostroventral thickening compared to non-brachycephalics
C) Similar luminal volume but diffuse thickened with increased prevalence of luminal debris compared to non-brachycephalics
D) No significant differences compared to non-brachycephalics
Answer = B
Brachycephalics have significantly thicker bulla wall & smaller luminal volume as well as thicker soft palates
36% of brachycephalics have bulla debris vs 0% nonbrachycephalic
Significant difference in mean soft palate thickness for dogs with material in the middle ear (12.2 mm) vs. air-filled bullae (9 mm)
Brachycephalic dogs have greater prevalence of subclinical middle ear effusion and smaller bulla luminal size than nonbrachycephalic dogs
Rostroventral margin of bullae thicker & thinner caudoventral in brachcephalics
T or F, dual phase contrast-enhanced CT is helpful in differentiating benign from malignant hepatic and splenic masses in dogs?
FALSE.
All of the following except which, are the most common findings associated with spinal lymphoma in MRI?
A) Multifocal locations affecting more than 1 compartment (e.g. intramedullary, extradural, paraspinal)
B) Spinal cord compression
C) Cortical vertebral osteolysis
D) STIR hyperintensity
Answer = C
Most common MRI characteristics of lymphoma affecting the spine and paraspinal soft tissues included multifocal lesions affecting one or more vertebrae, extension into the paraspinal soft tissues, and extension into the vertebral canal resulting in a variable degree of spinal cord compression
NO cortical vertebral osteolysis, changes confined to medullary cavity
A small ruminant presents with acute neurological signs. MRI shows asymmetrical, focal T2/FLAIR hyperintense brainstem lesions. The most likely differential diagnosis is what?
A) Suppurative inflammation (e.g. parasitic migration)
B) Listeric encephalitis
C) Enterotoxemia
D) None of the above
Answer = B
Toxic-metabolic disease -> bilaterally symmetrical GRAY matter (poliocephalomalacia cerebrum & forebrain) or WHITE matter (enterotoxemia – basal nuclei, corticospinal tracts of thalamus/midbrain/brainstem) lesions
Suppurative inflammation -> ASYMMETRIC FOCAL BRAINSTEM lesions (Listeria encephalitis), or lesions typical of intradural or dural abscess
Poliocephalomalacia in small ruminants is usually associated with ________ deficiency.
Thiamine deficiency
What is the typical distribution of brain MRI lesions in small ruminant with toxic or metabolic disease?
Bilaterally symmetrical gray matter (polioencephalomalacia) or white matter (enterotoxemia) lesiosn
What is the most common feline sinonasal neoplasm?
Nonepithelial origin tumor (e.g. lymphoma)
2nd most common = epithelial origin tumors such as adenocarcinoma, SCC, or undifferentiated carcinoma
Which of the following is NOT a common feature associated with nasal/paranasal neoplasia in cats?
A) Unilateral ethmoturbinate lysis
B) Unilateral ocular discharge
C) Soft tissue/fluid accumulation in sphenoid or frontal sinus
D) Lysis of the nasal septum or cribriform plate
Answer = D
- Common characteristics of nasal and paranasal neoplasia included osteolysis of the paranasal bones and nasal septum (particularly unilateral lysis of the maxilla or ethmoturbinates, bilateral lysis of the orbital lamina), turbinate destruction, soft tissue mass, soft tissue or fluid accumulation in the sphenoid or frontal sinuses, and extension of disease into orbital or facial soft tissues
- C/S significantly associated with neoplasia were unilateral ocular discharge & presence of a nasopharyngeal mass during endoscopic examination
- CT characteristics significantly associated with neoplasia included: unilateral lysis of ethmoturbinates, unilateral lysis of the dorsal and lateral maxilla, lysis of the vomer bone and ventral maxilla, and bilateral lysis of the orbital lamina; unilateral abnormal soft tissue/fluid within the sphenoid sinus, frontal sinus, and/or and retrobulbar space.
- Lysis of the maxillary turbinates, nasal septum, nasal bone, palatine bone, and cribriform plate were NOT significantly associated with sinonasal neoplasia.
What is the difference between calvarial hyperostosis syndrome and craniomandibular osteopathy? Which breeds are predisposed to each condition, respectively?
- Calvarial hyperostosis does NOT affect the mandibules/mandibular rami as craniomandibular osteopathy does.
- Craniomandibular osteopathy = bilateral, irregular, nonneoplastic osseous proliferative disease of young dogs usually affecting multiple bones of the cranium, occasionally extending to the metaphyses of long bones; Frontal, parietal, and occipital bones, tympanic bullae, mandibular rami, and the TMJs
- Calvarial hyperostosis seen in Bullmastiffs & English Springer Spaniels
- Craniomandibular osteopathy seen in Cairn Terriers, WHWT, Scottish terriers
Which of the following statement(s) is/are true regarding heart size and dexmedetomdine administration in cats?
A) VHS is increased on left lateral views following sedation
B) VHS is increased on right lateral views following sedation
C) VHS is increased on all views following sedation
D) Cardiac width is increased on VD/VD views following sedation
E) A & D
F) B &D
G) C & D
Answer = F
VHS on right lateral view significantly INCREASED after dexmed
Cardiac width INCREASED on VD/DV viewws ICNREASED after dexmed
A young horse presents for difficulty chewing. CT showed globoid-shaped mandibular condyles with coalescing hypodense regions. What is the most accurate conclusion regarding this finding?
A) The horse likely has evolving OC lesions of the condyles
B) The horse has degenerative bone cysts
C) The horse has evolving septic TMJ arthritis
D) The CT appearance of the horse is normal.
Answer = D
Horses < 1 yo commonly have altered shape & density of mandibular condyle (coalescing hypodensities)
Older horses commonly have ovoid hypodensities within mandibular condyles with surrounding sclerosis consistent with bone cysts (57% > 1 yo) & hyperdense intra-articular disc regions consistent with dystrophic mineralization almost exclusively occurred in ROSTRODORSAL lateral to mid region of disc
Bone cysts either present as small, single discrete foci in caudal aspect of condyle with little sclerosis & no articular communication OR as large irregular hypodense regions with or w/o articular communication and variable sclerosis in LATERAL aspect of condyle (NONE SEEN MEDIALLY)
90% lesions within condyle, 10% mandibular fossa of temporal bone
MALES more likely to have defined hypodensiites more than females
Association between disc mineralization and an inability to delineate the caudal aspect of the intra-articular disc in the soft tissue window
Disc mineralization significantly affected by age (0% in horses < 1 yo and increasing dramatically > 10 yo)
Bone cyst prevalence NOT associated with age
Intra-articular disc mineralization in the TMJ of an older horse is most likely located where?
A) Rostrodorsal
B) Caudodorsal
C) Rostroventral
D) Caudoventral
Answer = A
hyperdense intra-articular disc regions consistent with dystrophic mineralization almost exclusively occurred in ROSTRODORSAL lateral to mid region of disc
T or F, subchondral bone cysts within the TMJ of horses are age-related changes.
FALSE.
Disc mineralization significantly affected by age (0% in horses < 1 yo and increasing dramatically > 10 yo)
Bone cyst prevalence NOT associated with age
What are the two CT appearances of bone cysts within the TMJ in older horses? Is there a sex predisposition - yes or no?
Bone cysts either present as small, single discrete foci in caudal aspect of condyle with little sclerosis & no articular communication OR as large irregular hypodense regions with or w/o articular communication and variable sclerosis in LATERAL aspect of condyle (NONE SEEN MEDIALLY)
90% lesions within condyle, 10% mandibular fossa of temporal bone
MALES more likely to have defined hypodensiites more than females
Which of the following statement(s) is/are false?
A) Genetic predisposition for equine melanoma in gray -coated horses
B) Melanomas are usually numerous, well-defined heterogeneous hyperattenuating masses
C) Most common locations = mandibular salivary gland, near the larynx/pharynx, guttural pouches & adjacent to the tongue base
D) Up to 20% of masses may have regions of mineralization and hypoattenuating necrotici regions
FALSE answers = B and C
Common melanoma location in horse head = PAROTID salivary gland, guttural pouches, surrounding larynx/pharynx, & adjacent to HYOID apparatus
Other common locations = perineal region, tail base, lips, prepuce, eyes/eyelid
Genetic predisposition associated with gray hair coat
All melanomas HYPERattenuating precontrast compared to masseter muscles (HU 113) - HYPERattenuation likely due to melanin content
26% of melanoma masses mineralized & 20% had hypoattenuating regions (necrosis)
Usually NUMEROUS masses, well-defined & HOMOGENEOUS
Which horse breed is more likely to have an anomalous C6 vertebra?
Warmbloods
Anomalous C6 vertebra in horses is NOT significantly associated with all of the following EXCEPT……
A) Increased likelihood of cervical pain
B) Articular process OA
C) Sex/gender
D) Intravertebral sagittal ratios
Answer = A
Anomalous C6 vertebrae more common in Warmbloods
No association with sex, intravertebral sagittal ratios, or between C6 morphology & articular process OA
Anomalous C6 associated with increased liklihood of cervical pain (possibly associated with altered biomechanics & decreased ROM)
Higher proportion of horses with anomalous C6 had an intravertebral sagittal ratio < 0.5 which may indicate association with other C6 vertebral anomaly,
T or F, an anomalous C6 vertebra is a common finding?
TRUE. Found in up to 24% of horses
Which statement is correct?
A) Quadrigeminal cistern is H-shaped on volume-rendered images and is separated from the 3rd ventricle by a thin membrane that is isointense to brain parecnhyma on MRI & isoattenuating to soft tissues on CT
B) Supracollicular fluid accumulation is more common in young, female brachycephalic dogs
C) Predisposition for supracollicular fluid accumulation in Shih-Tzu, Maltese & Chihuahua
D) None of the above are true
Answer = C
Normal quadrigeminal cistern is H-shaped on dorsal images & separated from 3rd ventricle by a thin membrane (membrane isoattenuating to soft tissues on MDCT and isointense on MRI to brain parenchymaa;best appreciable on midsagittal plane)
On volume-rendered images, the cistern has a pyramid shape (aboral base, cranial apex)
Dogs with supracollicular fluid accumulations (SFA) significantly YOUNGER & SMALL BREED
Shih-Tzu, Chihuahua & Maltese predisposition for SFA
3 patterns of SFA: 1) 3rd ventricle -50%, 2) Quadrigeminal cistern – 14%, 3) Both 3rd ventricle & quadrigeminal –37%
SFA prevalence in male, brachycephalic dogs
Which MRI sequence is most beneficial for evaluation of supracollicular fluid accumulations?
A) T1
B) STIR
C) 3D FISP
D) Balance steady-state free precession
Answer = D
Balance steady-state free precession MR sequence was particularly useful in this study to obtain high quality MPR images of the subarachnoid spaces
T or F, fluoroscopic measurements of tracheal stent size are not statistically different than CT measurements although there is greater inter- and intraobserver variability.
FALSE.
Fluoroscopic measurements are ~0.2mm SMALLER in height and width versus CT.
Greater tracheal diameter & lower measurement variability with CT indicates this may be the best modality for appropriate stent selection
Tracheal stents are typically 10-20% greater than the largest tracheal diameter during max inflation
Low-attenuation filling defect occupying the entire lumen of the pulmonary artery and increased diameter of the pulmonary arteries with extensive filling defects are the two most common CT findings associated with _________ disease reported in human patients
Pulmonary artery sarcoma
these findings are NOT seen with pulmonary embolic disease
Describe the MRI findings commonly seen with spinal lymphoma on MRI?
- T1 hypo, T2/ASTIR hyperintense lesions with strong uniform enhancement
- usually multifocal and affecting more than one component of the spinal cord/vertebrae (e.g. vertebral body, cord compression, paraspinal involvement)
- NO cortical lysis
- STIR medullary hyperintensity
Regarding the effect of food bolus size and consistency during deglutition, which of the following statements is true?
A) Dogs positioned in lateral recumbency experience faster cervical esophageal transit times versus sternal recumbency
B) Max pharyngeal contraction and primary versus secondary peristalsis are affected by recumbency
C) Maximum pharyngeal contraction occurs earlier/faster with liquid food boluses versus solid food
D) Thoracic esophageal transit time is longer with small size solid food versus liquid boluses
Answer = D
However, NO significant difference in cervical or total esophageal transit time based on size or consistency
- A is false because sternal recumbency has faster transit time
- B is false because max pharyngeal contraction, mode of peristalsis & esophageal transit time are affected by bolus consistency (e.g. solid versus liquid)
- C is false because max pharyngeal contraction occurs later/slower with medium size solid food boluses versus liquid
- Additionally, primary peristalsis occurs more frequently with solid food boluses versus liquid
Which of the following is more sensitive and specific for recommending surgery associated with small intestinal mechanical obstruction, radiographs or CT?
Answer = radiographs
Radiography more sensitive (92% vs 83%) & specific (83% vs 72%) versus CT for recommending surgery [ but NOT statistically significant]
Which of the following is more sensitive and specific for detecting small intestinal mechanical obstruction, radiographs or CT?
Answer = CT
CT more sensitive (96% vs 79%) & specific (81% vs 69%) versus radiographs for detection of mechanical obstruction [NOT statistically significant]
Bowel diameter greater than _____times the L5 height has 50% probability of obstruction & greater than ______ times L5 height has 80% probability
A) 1.7 and 1.9
B) 1.5 and 1.8
C) 1.5 and 2.0
D) 1.6 and 2.2
Answer = A (technically 1.73 & 1.95)
Main pulmonary artery to aortic measurement ratio is performed on what echo view?
Right parasternal short axis view
Which echocardiographically derived measurement of main pulmonary artery to aorta ratio has 100% specificity for distinguishing normal dogs from those with pulmonary hypertension?
A) 0.98
B) 1.0
C) 1.14
D) 1.23
Answer = C
echocardiographic ratio of MPA:Ao exceeding 0.98 indicates MPA enlargement supportive of pulmonary hypertension (Se = 0.73; Sp = 0.76)
T or F, CT measurement of main pulmonary artery to aorta ratio is greater on expiratory views versus inspiratory?
FALSE.
Expiratory views have LOWER main pulmonary artery:aorta ratios versus inspiratory views
For which of the following disease processes is CT/CT arthrography LESS diagnostic compared to arthroscopy or U/S in the diagnosis of stifle disease in equines?
A) Subchondral cystic lesions of the proximal tibia
B) Articular cartilage defects of the medial femoral condyle
C) Ligament entheses of the cranial or caudal cruciates or craniomedial meniscotibial ligament
D) None of the above, CT or CT arthrography has no difference in diagnostic accuracy versus U/S or arthroscopy
Answer = B
- CT arthrography detected more defects in the cruciate ligaments, proximal tibia (subchondral cysts), & ligament entheses but was NOT reliable for medial femoral condyle articular cartilage defects
- Medial femoral cartilage defects most detected on arthroscopy (96%) & 60% on CTA
Describe the difference between central tarsal bone fractures in racehorses versus nonracehorses.
Central tarsal bone fractures in racehorses = slab fractures oriented in a dorsal plane with minimal to no displacement & best seen on lateromedial radiograph
Central tarsal bone fracture in NON racehorses = minimally or non-displaced slab fractures in a DORSOMEDIAL TO PLANTAROLATERAL orientation & only seen on plantarolateral-dorsomedial oblique views
Does dynamic subtraction imaging or paired pre- and postcontrast gadolinium images have better sensitivity for inflammatory intra-axial lesions?
Dynamic subtraction imaging has higher sensitivity 65% versus pre/postcontrast gadolinium images 48%
T or F, meningeal lesions are more frequently observed in both dynamic subtraction imaging and pre/postcontrast gadolinium images than intra-axial inflammatory lesions?
FALSE.
Intra-axial lesions were observed more frequently than meningeal lesions in both C-/C+ (43% vs. 31%) and DS images (61% vs. 22%).
Match the following to intervertebral disc protrusion or extrusion:
A) Lateralization of herniated disc material
B) Longer duration of C/S
C) Herniated material confined to disc space
D) Midline location
E) Partial disc degeneration
F) Single site affected
Disc protrusion = B, C, D, E
Disc extrusion = A, F
Disc protrusion = Longer duration of C/S, multiple sites, midline location, & partial disc degeneration
Disc extrusion = Single site herniation, lateralized location, & dispersed IV disc material not confined to the disc space, complete disc degeneration
T or F, a smartphone provides an acceptable interface for accurate diagnosis of small intestinal mechanical obstruction in dogs and cats
TRUE
With regards to diagnosis of small intestinal radiographic diagnosis of mechanical obstruction, what is the difference between recently qualified and more experienced radiologists?
A) Recently qualified radiologists have higher sensitivity and specificity
B) More experienced radiologists have higher sensitivity and specificity
C) Recently qualified radiologists have higher sensitivity and lower specificity compared to experienced radiologists
D) There is no difference between the two groups
Answer = C
Recently qualified radiologists have a high sensitivity and lower specificity. Specificity and thus overall accuracy tend to increase with experience
A dog presents with signs of lethargy, nasal discharge & coughing. Thoracic radiographs & other diagnostics are performed and the dog tests positive for canine influenza virus. Which of the following will most likely not be identified on radiographs?
A) Cranioventral distribution of parenchymal changes
B) Intrathoracic lymphadenopathy
C) Pleural effusion
D) Interstitial to alveolar pattern within multiple lung lobes
Answer = B
- Pleural effusion is possible, but uncommon
- NO dogs had intrathoracic lymphadenopathy or cranial mediastinal widening/pleural effusion
- Unstructured interstitial to alveolar pattern distributed within multiple lobes (right & left cranial, right middle) distributed cranioventrally, or less likely diffuse or caudodorsally
When using CT to screen for tooth resorption in cats, which of the following statements is FALSE?
A) Lesions are most commonly located at mandibular premolar 3
B) Lesions mostly involve the tooth roots and the cementoenamel junction
C) CT has good specificity and sensitivity for tooth resorptive lesions
D) Resorptive lesions are irregularly marginated, hypoattenuating defects
Answer = C
CT has poor sensitivity but excellent specificity for resorptive lesions
What is the optimal level of positive pressure that should be used to minimize hyperinflation & reduce effects of anesthesia-induced hypoinflation/atelectasis when performing thoracic CT breath hold techniques?
A) 8-10cm H20
B) 10-12cm H20
C) 15-17cm H20
D) 18-20 cm H20
Answer = B
Homeotic and/or homologous variations of the cervical vertebral column in horses on CT may be seen in up to what percent of horses?
A) < 25%
B) 29%
C) 33%
D) > 45%
Answer = C
33% homologous transposition of C6 transverse process
Transposition of the ventral transverse process of C6 is common in what breed of horse?
Warmbloods
T or F, the presence of a homologous cervical vertebral change in horses is significantly increased in horses with C/S of cervical pain?
FALSE.
No significant difference in the # of cervical vertebral anomalies between horses with or without C/S nor between mature or juvenile horses
Which of the following is TRUE regarding equine stifle osteoarthritis?
A) Stifle OA has no association with bone mineral density
B) There is low sensitivity and specificity on radiographs & CT for the detection of subchondral bone sclerosis & femoral condylar flattening
C) Lateral femorotibial joint is most commonly affected
D) Caudo-10°proximo-5°lateral-craniodistomedial oblique (Ca10Pr5L-CrDiMO) radiographic projection is helpful for detection of medial femoral condyle osteophytes
Answer = B
A is false because OA does has an association with DECREASED bone mineral density
C is false because the medial femorotibial is most affected
D is false because that view is helpful for detection of intercondylar osteophytes
Which of the following has the most accurate measurement of cartilage thickness of the equine metacarpophalangeal joint compared to gross measurements?
A) MRI
B) MR arthrography
C) CT arthrography
D) None of the above have measurements significantly consistent with gross measurements
Answer = D
- No modality had measurements that were consistent with gross cartilage thickness
- Both MR & CTA measurements subjectively smaller than gross measurements
T or F, diagnostic accuracy of thoracolumbar intervertebral disk protrusion versus extrusion is significantly influenced by degree of experience
True
Using the guidelines that midline location & partial disk degeneration were associated with disc protrusion versus presence of a single disk herniation & disk material dispersal are associated with disk extrusion, what is the relationship between accuracy and interobserver agreement on the diagnosis of thoracolumbar IV disc protrusion versus extrusion?
Both accuracy & interobserver agreement IMPROVE when the guidelines are used in the diagnosis of thoracolumbar IV disc disease.
Accuracy improves from 71 to 80% and interobserver agreement increased from fair to moderate
Regarding ultrasonography of small intestinal wall layering in dogs, which of the following is true?
A) 100% had hyperechoic muscularis line parallel to the serosa consistent with fibrous tissue
B) There is significant difference between U/S and histology measurements of the small intestine
C) 1/3 of all ileal samples showed an asymmetric hypoechoic extra submucosal layer consistent with lymphoid tissue/Peyer’s patches
D) Dual mucosal echogenicity is due to intestinal villi which create an inner mildly echogenic layer and outer hypoechoic lamina propria
Answer = D
A is false because this hyperechoic line represents the interface between the longitudinal & circular muscularis layers consistent with the myenteric plexus
B is false because there is NO significant difference in layer measurements aside from the serosa
C is false because in dogs the additional layer is circumferential and is a hyperechoic mucosal line parallel to the submucosa representing Peyer’s patches. The asymmetric hypoechoic extra submucosal layer is lymphoid tissue in CATS
T or F, intestinal mucosal echogenicity can be increased following food intake, regardless of fat content.
TRUE
T or F, hepatic portal and parenchymal gas can result from GI translocation of gas if mucosal integrity is compromised
TRUE
Describe the gastrointestinal transit time(s) for the following in habituated Labrador Retrievers on GI positive contrast fluoroscopy?
1) T1/2 gastric emptying time
2) Time at which barium is 1st seen in small intestine
3) Peak filling time of small intestine & proximal large intestine
4) Distal large intestinal filling time & peak filling
1) T1/2 gastric emptying time = 1-2 hours post ingestion
2) Time at which barium is 1st seen in small intestine = 30 min post ingestion
3) Peak filling time of small intestine & proximal large intestine = 3 hours post ingestion
4) Distal large intestinal filling time & peak filling = large intestine empty for first 2 hours, progressive filling between 2-5 hours post ingestion, & peak filling from 6 hours onward
In dogs with medial compartment elbow erosion, which of the following is FALSE?
A) < 25% have concomitant flexor enthesopathy
B) There is no agreement between CT and arthroscopy for presence of medial humeral condyle subchondral bone defect
C) Significant agreement between CT & arthroscopy for a fragmented medial coronoid process
D) Three most common findings are periarticular osteophytosis, abnormally shaped medial coronoid process & medial humeral condyle subchondral bone defect
Answer = A
A is false because up to 71% have abnormal appearance of medial humeral epicondyle consistent with concomitant flexor enthesopathy
NOTE: Accurate assessment of the extent of elbow cartilage lesions still requires arthroscopy and CT CANNOT replace arthroscopy for diagnosis of medial compartment erosion
Truncation or Gibb’s artifact occurs as a result of __________.
Truncation artifact = abnormal signal intensity that occurs parallel to an interface of tissues of markedly different signal intensities (e.g. tissue-fluid interface on T2W images)
Which of the following is TRUE regarding truncation artifact?
A) In low-resolution images, the artifact appears as multiple hyperintense zones on T2W images
B) In high-resolution images, the artifact appears as a single wide central hyperintense zone on T2W images
C) Artifact is minimized by decreasing pixel size, decreasing FOV, or increasing matrix size
D) Artifact can be completely eliminated by increasing spatial resolution
Answer = C
On low resolution images, the artifact is a single wide hyperintense zone on T2
On high resolution images, the artifact is multiple narrower hyperintense zones on T2
On T1 images the artifact is HYPOintense
Artifact CANNOT be completely eliminated but can be minimized by increasing spatial resolution (e.g. decreasing pixzel size, inc matrix size, dec FOV)
Magnetic susceptibility artifact is seen on _____ sequences, but never on _____ sequences.
Seen on gradient recall echo sequences (GRE) but never on fast spin echo (FSE)
- Gradient recall echo sequences more senstiive to magnetic susceptibility than spin echo b/c the dephasing & rephasing of the FID signal occur in the same direction relative to the main magnetic field, owing to the absence of the 180° refocusing pulse, consequenctly cancelling the effects of magnetic field inhomogenities on spin dephasing does not occur
Magnetic susceptibility artifacts increase with ___________ (what technical parameter).
Increasing magnetic strength
Regarding MRI evaluation of hepatocellular carcinoma in dogs, which of the following statements is FALSE.
A) No enlarged hepatic lymph nodes were found in any dog
B) Time to maximum enhancement of normal liver parenchyma is ~20min
C) All hepatocellular carcinoma lesions were hypointense to normal parenchyma on T1 and T2 postcontrast GRE sequences
D) Hepatic lesions not identified on other imaging modalities were seen on MRI in 43% of cases
E) B & C are false
F) B,C, & D are false
G) All statements are false
Answer = E
B is false because time to maximum enhancement is ~10min not 20min
C is false because all hepatocellular carcinoma lesions are hypointense to normal parenchyma on postcontrast T1W GRE sequences, no mention of T2W postcontrast sequences
Hepatic lesions NOT identified on previous imaging were found using Gd-EOB-DTPA in 43% of cases
NO enlarged hepatic lymph nodes in any dog. Non-lymph node extrahepatic lesions were found in 28% of dogs
Which of the following is TRUE regarding articular cartilage studies in canine stifle joints?
A) Articular cartilage is accurately evaluated on radiographic images
B) MRI overestimates cartilage defect depth & width, but correlation between MRI and histopath is better for lesion width > depth
C) Cartilage defects result in significantly greater T2 relaxation times
D) 90% of cartilage defects are correctly identified on small FOV 3T MRI
Answer = C (significantly greater T2 relaxation time = more hyperintense lesion)
A is false because articular cartilage CANNOT be evaluated on radiographs
B is false because correlation is better for lesion depth > width
C is false because 98% of cartilage defects are correctly identified
Which modality is 100% sensitive and specific for gallbladder wall rupture & necrosis?
A) Post contrast T1 MRI
B) Nuclear scintigraphy
C) Conventional U/S
D) Contrast-enhanced U/S
Answer = D
In dynamic sonography of the equine metacarpo(tarso)phalangeal digital flexor tendon sheath, those horses affected with palmar/plantar annular ligament desmitis had ________ gliding motion between the annular ligaments and flexor tendons and _______angulation of the long linear echoes of the tendon compared to the normal horses.
A) Restricted; increased
B) Restricted; decreased
C) Unrestricted; increased
D) Unrestricted; decreased
Answer = A
Controls = unrestricted gliding and 0-13 degrees of angulation of long linear echoes
Affected desmitis horses = restricted gliding and increased long linear echo angulation up to 20-35 degrees
T or F, a gap between the DDFT and SDFT is found in normal horses on U/S of the digital flexor tendon sheath however a larger percentage of horses with palmar annular ligament desmitis show evidence of this.
TRUE.
Finding of a gap between DDFT and SDFT was found in a lower % of control horses (25%) versus affected desmitis horses (75%) however the gap size is slightly larger in control horses & likely represents normal physiology
The major component of pathologic dystrophic and metastatic calcification is ________(which mineral) which can lead to accumulation of 99mTc-MDP on nuclear scintigraphy studies.
Calcium phosphate
Pilomatricoma is a follicular tumors originating from cells of the hair bulb. Up to 1/3 tumors of these tumors are malignant with a predilection for _____ metastasis.
bone metastasis
T or F, synthetic progesterone administration for contraceptive use in dogs has minimal to no side effects and can safely be administered long term?
FALSE.
Synthetic progesterone (medroxyprogesterone acetate) results in endometrial proliferation & inhibits myometrial motility leading to weight gain, diabetes mellitus, mammary gland tumors, endometrial hyperplasia & pyometra
Dystrophic endometrial mineralization should be considered on the DDX list when multiple hyperechoic foci accompanied by acoustic shadowing are observed along the uterine wall in dogs with a long-term synthetic progesterone treatment history
