VRU 2017 Flashcards
Which pancreatic lobe is consistently bigger in cats on CT?
The left.
Mean attentuation of a normal cat pancreas on CT? During arterial, portal and delayed?
48 HU is normal
79 HU arterial
166 HU portal
126 HU delayed
Mortier et al: CT findings in dogs with Crenosoma vulpis, what were the four consistent findings in all dogs?
Diffuse bronchial wall thickening
Peribronchial ground glass
Consolidation of pulmonary parenchyma
Cylindrical bronchiectasis
Mortier et al: CT findings in dogs with Crenosoma vulpis, where does crenosoma vuplis live?
Trachea, bronchi and bronchioles of canids
Mortier et al: CT findings in dogs with Crenosoma vulpis, where in N.America is this found?
Atlantic Canada
What is this representing?
Parenchymal bands - Fibrosis of the septa from chronic inflammation
What causing the reactivation of Toxo in dogs and cats?
Immunosuppressants…specifically cyclosporine.
Specchi et al: Sentinel clot sign in canine; What is the HU range for the sentinel clot sign?
43-70 (56 mean)
THE HIGHER THE HU, THE CLOSER THE CLOT IS TO THE SOURCE
Specchi et al: Sentinel clot sign in canine; What is the HU range for a hemoab?
20-45 HU (34 mean)
Specchi et al: Sentinel clot sign in canine; What is the HU range for high protein fluids??
0-15 HU
Specchi et al: Sentinel clot sign in canine; What if the HUs are above 85 in a “clot” in post contrast images?
Think still bleeding and leaking of contrast
Think accidentally including some tissue.
Pollard et al: Diagnostic outcome of swallowing studies in dysphagic dogs: What were the main areas of dypshagia noted in this cohort of dogs?
- Lower esophageal sphincter (45%)
- Esophageal (45%)
- Multiple areas (38%)
- Normal study (28%)
- Pharyngeal (13%)
- Cricopharyngeal (9%)
Pollard et al: Diagnostic outcome of swallowing studies in dysphagic dogs: Elevated pharyngeal constriction ratio was related to what type of dysphagia?
- Pharyngeal
- Cricopharyngeal
- Esophageal
Cricopharyngeal ratio is measured with liquid barium.
Full contraction:Full relaxation
Pollard et al: Diagnostic outcome of swallowing studies in dysphagic dogs: What is the esophageal/cricopharyngeal bar and what does it represent?
Don’t know and was related to abnormal bolus transfer.
Pollard et al: Diagnostic outcome of swallowing studies in dysphagic dogs: A lower percentage of primary esophageal peristaltic wave was associated with what?
- Cricopharyngeal
- Pharyngeal
- Primary esophageal motility
Pollard et al: Diagnostic outcome of swallowing studies in dysphagic dogs: Delayed upper esophageal sphincter openins was aocciated with what?
Cricopharyngeal disorders. - likely neuromuscular related.
Bush et al: CT characteristics of thyroid glands in hyperthroid cats pre and postmethimazole treatment compare to euthyroid cats: What was the significant difference between pre and post methimazole cats?
Thyroids of postmethimazole cats were less heterogeneous and had decrease attenuation.
The size stayed the same which was larger than euthyroid cats. (785mm3 vs 154mm3)
Bush et al: CT characteristics of thyroid glands in hyperthroid cats pre and postmethimazole treatment compare to euthyroid cats: How does methimazole work?
Blocks organification
2-4weeks to achieve full effect
2.5mg q12 to 10mg q12 - size of needed dose correlated with pretreatment thyroid volume.
Bush et al: CT characteristics of thyroid glands in hyperthroid cats pre and postmethimazole treatment compare to euthyroid cats: What is the normal cats thyroid size? Attenuation?
16.5mm x 2mm x 4.3mm (L x W x H)
113mm3 mean lobe
215mm3 mean gland
123 HU normal
65 HU in hyperthyroid cats
What are DDX for an intraventricular tumor having drop mets?
- Choroid plexus tumor
- Epndymoma
- Glioma (oligodendroglioma)
- Round cell
Gendron et al: Pathogenesis of paraesophageal empyema in dogs on CT and rads: Where and what is the mediastinal serous cavity?
Extension of the omental bursa into the dorsal caudal mediastinum but separated by diaphragm.
It is to the right of the esophagus between the heart base and diaphragm
Mesothelial cells line the cavity
Created by the right pulmonary vein, right pulmonary ligament and caudal medistinum
MSC on the picture
Gendron et al: Pathogenesis of paraesophageal empyema in dogs on CT and rads: Define an empyema?
Empyema is an accumulation of purulent material in an existing body cavity.
Watton et al: Malignant vs inflammatory pleural effusion in dogs on CT: What were common features of dogs with malignant pleural effusion?
- Older
- More frequent pleural thickening
- Thickening of the parietal pleura only
- More marked thickening
- Thoracic wall invasion - only in malignant processes
Attenuation, distribution, volume, contrast or lymphadenopathy had no bearing on if it was malignant or not
Frederik et al: Rad measurements of hoof balance influenced by horse’s stance: The hoof pastern angle was influenced by what change in the horses stance? What joint of that angle was most effected?
- Craniocaudal changes in stance influenced the hoof/pastern axis
- The distal interphalangeal joint angle was most effected.
Frederik et al: Rad measurements of hoof balance influenced by horse’s stance: Did the width of the interphalangeal joints or the distal phalanx height change with lateromedial stance variation? Did they change with the angle of the beam?
NO and No.
Specchi et al: Sentinel clot sign on CT: What is the mean and range of the HUs for the sentinel clot sign? How does that relate to a hemoabdomen?
Sentinel clot sign - 56 HU (43-70) - THE HIGHEST ATTENUATING HEMATOMA is expected to be the closest to the bleeding site aka SENTINEL clot sign.. not just a clot. So have to evaluate all the clots
Normal - 34 HU (20-45)
So anything above 45 is a clot but may not be the sentinel one.
Fuerst et al: CT of 24 dogs with liposarcoma: what are characteristics that differentiate liposarcs from infiltrative lipomas or lipomas?
- All liposarcs contrast enhance
- Heterogenous internal attenuation
- Focal areas of fat attenuation (15 HU (-50 - 50 HU)
- Mineralized foci (23%)
So if you see an infiltrative mass, that is mixed attenuating, contrast enhancing and contains at least one focus of fat think liposarc…. you don’t need the focus of fat however.
Spoldi et al: CT features of adipose masses in dogs and cats: What are the features that differentiate lipomas from infiltrative lipomas?
- Irregular in shape - infiltrative lipomas
- Hyperattenuating linear components (100%) - Though necrotic lipomas have these as well (70%).
The picture shows a necrotic lipoma (left) vs infiltrative lipoma.. the biggest difference is the margins.
Spoldi et al: CT features of adipose masses in dogs and cats: What components were found to differentiate liposarcs from the other 2 types?
- Multinodular soft tissue component
- Regional lymphadenopathy
- Mineralization
- Heterogeneous mass
- Contrast enhancement.
Oliphant et al: Midline shift and survival of dogs with MUO: What was the medial survival for dogs with no shift vs dogs with a shift?
906 days without a shift and 84 days with a shift - this was NOT significant I guess, but clinically relevant.
Conclusion was that a midline shift of 0.04 - 0.3cm did not have a shorter survival time. This was the range of shift in this population.
Oliphant et al: Midline shift and survival of dogs with MUO: What was significantly associated with survival?
- Age at the time of diagnosis (older was shittier)
- CSF TNCC
Moore et al: Spinal mast cell tumor in dogs: What were the clinical signs?
Paraspinal hyperesthesia
Subacute progression myelopathy
Moore et al: Spinal mast cell tumor in dogs: What were the characteristics of these lesions?
Varied
-
ALL were extradural with varied distribution
- Epidural
- Paravertebral
- Polyostotic
Survival depended on grade (high vs low grade scale) but there were only 4 dogs.
This can be “mets” from cutaneous or disseminated disease - though primary tumor of the epidural space was noted.
Sievert et al: MRI spect findings in dogs with tick-borne encephalitis: What abnormalities were noted in the dogs with tick-borne encephalitis?
- Mild-moderate decreases in N-acetyl aspartate and creatine peaks
- Mild increases in glutamate/glutamine peaks
Europe disease
Partlow et al: US characteristics of hair shafts in synovial structures: What were the characteristics of a hair shaft in synovial structures?
- Thin
- Linear
- Hyperechoic
- NO shadow
All these horses had a history of lacerations in the past! So this is just a migrating foreign body.
Bucy: What effects the outcome of US-guided heat ablation for hyperparthyroid dogs; What affected the outcome fo heat ablation?
- Larger parathyroid nodules
- Concurrent hypothyrodism
They were associated with treatment failure.
Bucy: What effects the outcome of US-guided heat ablation for hyperparthyroid dogs; How successful was heat ablation in this population?
70% successful.
Felumlee et al: Repeatability of GFR determination via 99mTc DTPA: What was the conclusion of this paper?
Reliability for GFR measurements were high among experienced readers and variations were limited which did not lead to changes in clinical classification.
Felumlee et al: Repeatability of GFR determination via 99mTc DTPA: What is the predominant source of variation in GFR studies using 99mTc?
Drawing the ROIs
Lablee et al: Comparsion between thoracic rads of thoracic disease in dyspneac rats: What was the most helpful lesion for differentiating neoplasia and infectious thoracic diseases in rats?
Cranial mediastinal lesions
Lamb et al: CT of dogs with wooden foreign bodies: What was the sensitivity and specificity of CT when detecting wooden foreign bodies?
Sensitivity - 80%
Specificity - 93%
Lamb et al: CT of dogs with wooden foreign bodies: What were the characteristics of wooden FBs?
- Rectanular/linear
- Median HU of 111HU
Lamb et al: CT of dogs with wooden foreign bodies: What was significantly associated with chronic disease and what was associated with acute disease?
Chronic
- Foreign material
- Cavitary lesions
- Fat stranding
- Periosteal reaction
Acute
- Gas in soft tissues
Fitzgerald et al: Improving cospicuity of the GI wall using dual energy CECT: At what time period after CE injection did the mucosal surface enhance of the intestines and stomach?
30s
Fitzgerald et al: Improving cospicuity of the GI wall using dual energy CECT: What was the conclusion?
Dual energy CECT can increase the conspicuity of the GI wall and allow you to evaluate the mucosal surface of the stomach and SI.
Secrest et al: Comparison of transverse CT excretory urography vs MIP for ectopic ureters in dogs: What was conclusion of this study?
This study compare transverse source computed tomographic excretory urography (CTEU) images to two, five, and 10 slab thick MIP images for diagnosing canine ectopic ureters.
They found that thin sliced MIP (2-5 slab thick) improved reader confidence significantly - however, no significance in diagnostic accuracy was noted.
Having a radiologist read it increased accuracy.
Djernes et al: Effects of beam angle and distortion on width of equine thoracolumbar interspinous spaces: How does beam angle affect the width of interpinous spaces in horses? What was the gold standard for the widths in this study?
Decreases them as the get further away from focus. This decrease became significant at position +3/-3 spinous spaces from focus
Gold standard was dorsal recon of CT.
Djernes et al: Effects of beam angle and distortion on width of equine thoracolumbar interspinous spaces: What is the limit for interspinous space on the lateral projections?
<4mm - too narrow
Djernes et al: Effects of beam angle and distortion on width of equine thoracolumbar interspinous spaces: What are the 4 things that affect geometric distortion?
- Beam angle
- Object to plate distance
- Centering object
- Source to plate distance
Djernes et al: Effects of beam angle and distortion on width of equine thoracolumbar interspinous spaces: How did interspinous widths change when comparing focus positioned rads and CT on backs with kissing leasions?
Rads - much small space when compared to CT
Soultani et al: Sentinel LN mets in canine mammary tumors using CT indirect lymphography: What feature showed the highest sensitivity, specificity and accuracy when diagnosing metastatic disease in sentinel lymph nodes?
- Absence of opacification or heterogeneous opacification 1 min after CE = highest (93% sen, 100%sp, 98%acc)
- Having an absolute density of lower than 444 HU in the center of the lymph node (93%sen and 75%sp)
1 ml was injected
Soultani et al: Sentinel LN mets in canine mammary tumors using CT indirect lymphography: What features had the lowests sensitivity and specificity?
Size and shape
Zindl et al: Effects of image plane, patient positioning and foraminal zone on MRI measurements of the canine LS foramina: What parameters of imaging and positioning caused the LS foramen to be smaller?
- Oblique plane acquistion (image showing the difference between standard parasagittal (left) and oblique planes (right))
- Extended limb positioning
This significance difference became even more stark when you did both together. Oblique plane and extended limb.
Pelizzone et al: CT features of pseudo-odontomas in prairie dogs: What CT features confirms maxillary pseudo-odontomas?
Image is normal tooth
- Hyperattenuating pulp and dentin in the reserve crown and apical zone.
- Enlargement of apical zone with a globular/multilobular hyperattenuating mass haphazardly arranged, encroaching on midline and growing caudoventrally.
- Hard palate deformation and loss of palatine bone
- Common nasal meatus was partially or totally obliterated.
Age range between 3-6 years
Roels et al: Comparison between sedation and anesthesia in CT of canine pulmonary fibrosis in Westies: What is the picture structure called? What does it represent?
- Left picture - Subpleural bands - refers to thin curvilinear opacities, 1-3 mm in thickness, lying less than 1 cm from and parallel to the pleural surface
- Fibrosis
- Atelectasis
- Pulmonary edema
- Right picture - Parenchymal bands
- They represent pleuroparenchymal fibrosis
- Many etiologies:
- SIRS
- Asbestosis
- Fungal etiologies
- Many etiologies:
- They represent pleuroparenchymal fibrosis
Majeski et al: Indirect CT lymphography for iliosacral mapping: What body positioning was recommended? What timing?
Supported sternal body positioning.
1 min post injection.
Vernon et al: Vertebral venous system abnormalities identified with MRI in sighthounds: What three structures make up the vertebral venous system?
- Internal vertebral venous plexus
- Surrounds the cord in the epidural space
- These vessels lie centrally and ventrally, and move laterally and dorsally at the intervertebral foramen
- External vertebral venous plexus - connected to the internal by intervertebral veins
- Basivertebral veins
They all interweave.
Coia et al: Retrospective evaluation of the thoracic CT in dogs with Angiostrongylus vasorum: Where and what were the primary CT changes noted?
- Grond-glass to consolidation
- Location was pleural to subpleural - not peribronchial
Other stuff: Nodules, bronchiectasis, TB lymphadenopathy
Olive et al: Metacarpophalangeal joint injury on MRI - Standardbreds vs thoroughbreds: Thoroughbreds developed more what while standardbreds develop what more often?
Thoroughbreds
- Stress fractures
- Subchondral sclerosis
- Bone marrow lesions
Standardbreds
- More sites of subchondral bone defect
- More synovitis
- More Joint capsule thickening.
- More dorsomedial location of subchondral bone defect
Scarpante et al: MRI of leukoaraiosis: What is this?
Bilateral, symmetrical WHITE matter lesions identified in brains of elderly humans.
T2 hyperintense with no contrast.
It is just an age related change.
Scarpante et al: MRI of leukoaraiosis: What is the virchow-robin space?
It is the space inbetween the vasculature and brain pia that is created when you have a perforating vessel into the brain.
Rutherford et al: Assessment of CT derviced cricoid cartilage and tracheal dimensions in BCS dogs: What two measurements were used in this study?
Transvere area of the cricoid cartilage and trachea at the level of C4.
Adams et al: Thoracic rad changes and association with severity of pulmonary hyertension: What radiographic findings were significantly associated with increasing pulmonary hypertension?
- Right ventricular enlargement (reverse D)
- 3/5 - 2/5 rule
- MPA enlargement
- Caudal lobar artery enlargement by the 3rd rib.
- The largest visible caudal lobar artery immediately cranial to the first branch and compared to 3rd rib on that side
Pont et al: MRI features of idiopathic oculomotor neuropathy in dogs: What were the characteristics (clinical and MRI)?
- All dogs were unilateral involvement
- Half improved without treatment - Half did not improve dispite treatment
- MRI features were mixed
- No to marked enlargement
- No to marked CE which was either focal or diffuse
Culp et al: Angiographic anatomy of the major abdominal arterial blood supply: What vessel is the first to come off the aorta in the abdomen? And what does it branch into?
Celiac
Into the left gastric, hepatic and splenic aa.
Culp et al: Angiographic anatomy of the major abdominal arterial blood supply: List the list of arteries, from cranial to caudal, that come off the aorta?
- Celiac
- Left gastric
- Splenic
- Hepatic
- Cr Mesenteric
- Jejunal
- Ileocolic a
- Right colic
- Middle colic
- Phrenicoabdominal
- Renal
- Ovarian
- Caudal mesenteric
- Left colic
- Cranial rectal
- Deep circumflex iliac
- External iliac
- Internal iliac
- Median sacral
Shields et al: Abnormal imaging of the femoral third trochanter in horses: What is the prognosis for horse to return to function?
Less favorable.
Jurkoshek et al: Effect of angle slice aquistion on CT cervical veterbral column in GD: Which part of the spine had different transverse measurements between the two measurement schemes (picture)?
The cranial aspect of the vertebrae (not the middle or caudal). Likely due to the funnel shape of the affected vertebra.
So the author recommends standard imaging protocol for morphometric evaluations.
US elastography of the liver, spleen, kidneys and prostate in normal dogs: What are the four types of elastography and how are they used?
- Strain - elasticity is measured under strain from a external compressive force using the US probe or pulsation - THIS IS encoded as a color-map over a B mode image - THIS IS Operator dependent and an egg shell effect can happen where the outer margins of a lesion are hard and therefore does not allow strain to be transferred internally.
- Tension
- Transient
- Shear-wave - Focused acousted radiation force from a linear probe… A low freq pulse is produced and propagated through a tissue…This creates shear waves through the tissue at a perpendicular angle (think of the low freq impulse as a stone and the waves in the water as the shear waves)… a high freq wave follows and maps how fast the shear waves are propagating (shear waves are 1000x slower and attenuate 10000x faster). Relationship between shear velocity and shear modulus are expressed in a color bar.
