NAVLE Diagnostic Imaging Interpretation Questions and Answers

Question 1

A 7-year-old Great Dane presents with acute, non-productive retching, hypersalivation, and a distended, tympanic abdomen. A right lateral abdominal radiograph is taken. Which radiographic finding is most pathognomonic for gastric dilatation-volvulus (GDV)?

Accepted Answer

A soft tissue opacity compartmentalizing the gas-filled stomach, creating a 'double bubble' appearance.

Answer

The classic radiographic sign for GDV on a right lateral view is the compartmentalization of the stomach by a soft tissue band, which is the pylorus folding over the fundus. This creates what is often described as a 'double bubble', 'Smurf hat', or 'Popeye arm' appearance and is pathognomonic for the condition.

Question 2

A 5-year-old Siamese cat is presented for a chronic, intermittent cough and occasional wheezing. Thoracic radiographs are performed. Which of the following radiographic patterns is most consistent with a diagnosis of feline asthma?

Accepted Answer

A prominent bronchial pattern, characterized by 'doughnuts' and 'tramlines', with evidence of lung hyperinflation.

Answer

Feline asthma is an inflammatory condition of the lower airways. Radiographically, this manifests as a prominent bronchial pattern due to the accumulation of inflammatory cells around the airways. These thickened bronchial walls are seen as 'doughnuts' (end-on view) and 'tramlines' (long-axis view). Air trapping due to bronchoconstriction can also lead to lung hyperinflation.

Question 3

A 10-year-old Quarter Horse with chronic, bilateral forelimb lameness undergoes a radiographic examination of the feet. Which of the following radiographic findings is most indicative of navicular disease (podotrochleosis)?

Accepted Answer

Enlarged, flask-shaped synovial invaginations ('lollipops') on the distal border of the navicular bone.

Answer

While many radiographic changes can be seen with navicular disease, the presence of more than 6-7 enlarged, flask-shaped or branching synovial invaginations (vascular channels) on the distal border is a classic and significant finding. Other key signs include flexor cortex erosions and medullary sclerosis.

Question 4

Which of the following common canine uroliths is most likely to be radiolucent on survey abdominal radiographs, often requiring contrast cystography or ultrasonography for diagnosis?

Accepted Answer

Ammonium Urate

Answer

Ammonium urate and cystine uroliths are typically radiolucent or only faintly radiopaque, making them difficult to see on standard radiographs. In contrast, struvite and calcium oxalate uroliths are mineral-dense and almost always radiopaque.

Question 5

A veterinarian performs an abdominal ultrasound on a dog with acute vomiting and anorexia. Which finding is most specific for a mechanical small intestinal obstruction?

Accepted Answer

A segment of intestine is severely dilated with fluid (>1.6 times the diameter of the aorta) proximal to a distinct transition point.

Answer

The most reliable ultrasonographic sign of a mechanical small intestinal obstruction is segmental dilation of the intestine proximal to the obstruction. A commonly used objective criterion is a small intestinal diameter greater than 1.6 times the diameter of the aorta. Other signs include a visible foreign body, plication, or intussusception.

NAVLE - North American Veterinary Licensing Examination Practice Test

NAVLE - North American Veterinary Licensing Examination Practice Test

NAVLE Diagnostic Imaging Interpretation Questions and Answers