Small Animal Diagnostic Imaging Flashcards

A 3-year-old German Shepherd Dog has progressive pelvic limb ataxia. MRI reveals an intramedullary T2-hyperintense lesion at L4 that does not contrast-enhance. The most likely diagnosis is:

Answer: Fibrocartilaginous embolism

Fibrocartilaginous embolism (FCE) typically appears as an intramedullary T2 hyperintensity without contrast enhancement, in young to middle-aged large breed dogs with acute onset.

Which positional radiograph is recommended to evaluate for pneumothorax when only a small amount of free pleural air is suspected in a dog?

Answer: Standing lateral with horizontal beam

A standing lateral with a horizontal beam allows free pleural air to rise to the highest point (dorsal), making even small pneumothoraces visible between the lung and dorsal thoracic wall.

In nuclear scintigraphy used in veterinary medicine, which radiopharmaceutical is most commonly used for bone scanning in dogs?

Answer: Technetium-99m methylene diphosphonate (MDP)

Tc-99m MDP (methylene diphosphonate) accumulates in areas of active bone remodeling and is the standard radiopharmaceutical for skeletal scintigraphy in small animals.

On thoracic radiographs, a cat with hypertrophic cardiomyopathy (HCM) most commonly shows which cardiac silhouette shape on the VD view?

Answer: Valentine heart shape (biatrial enlargement)

HCM in cats classically produces a 'valentine heart' shape on VD radiographs due to bilateral atrial enlargement, though some cats have relatively normal-appearing hearts.

Which ultrasound finding is most specific for portal hypertension in a dog?

Answer: Acquired portosystemic shunting vessels

Acquired portosystemic collateral vessels (multiple tortuous vessels in the region of the left kidney or spleen) are the most specific ultrasound sign of portal hypertension.

A dog presents with a suspected diaphragmatic hernia. Which radiographic finding would MOST suggest a peritoneopericardial diaphragmatic hernia (PPDH) rather than a traumatic diaphragmatic hernia?

Answer: Enlarged globoid cardiac silhouette without pleural effusion

PPDH is a congenital defect where abdominal organs herniate into the pericardial sac, causing an enlarged cardiac silhouette, unlike traumatic hernias where organs enter the pleural space.

On dental radiographs of a dog, which finding indicates endodontic disease requiring root canal therapy or extraction?

Answer: Periapical lucency (halo) at the root tip

A periapical lucency (radiolucent halo) at the root apex indicates periapical abscess or granuloma from pulp necrosis, confirming endodontic disease.