VTNE Diagnostic Imaging Techniques 5

Question 1

Which artifact on MRI appears as alternating bright and dark bands and is caused by motion during image acquisition?

Accepted Answer

Ghosting (motion artifact)

Answer

Ghosting or motion artifact creates ghost images or banding in the phase-encode direction due to periodic motion (e.g., breathing, cardiac pulsation) during the MRI acquisition.

Question 2

A double-contrast gastrogram is performed by introducing iodinated contrast followed by air. The purpose of the air is to:

Accepted Answer

Distend the stomach lumen to coat the mucosal surface with contrast

Answer

Air distends the stomach so that the positive contrast agent coats the mucosal folds, allowing mucosal detail and wall lesions (e.g., ulcers, masses) to be seen clearly.

Question 3

Which radiographic sign indicates free gas in the peritoneal cavity (pneumoperitoneum)?

Accepted Answer

Gas opacity between the liver and diaphragm on a standing lateral or DV view

Answer

Free peritoneal gas rises to the highest point and is visible as a radiolucent stripe between the liver and diaphragm on a standing lateral or horizontal-beam view.

Question 4

In ultrasound physics, 'resolution' refers to the ability to distinguish two structures as separate. Which type of resolution is MOST affected by transducer frequency?

Accepted Answer

Axial resolution

Answer

Axial resolution (along the beam axis) is determined by pulse length and wavelength, both of which improve with higher transducer frequency, allowing finer discrimination along the beam path.

Question 5

A dog has a suspected portosystemic shunt. Which imaging modality provides the MOST definitive pre-surgical mapping of shunt vasculature?

Accepted Answer

CT angiography

Answer

CT angiography provides three-dimensional vascular mapping with high spatial resolution, allowing precise identification of shunt location, number, and anatomy critical for surgical planning.

VTNE - Veterinary Technician National Examination Practice Test

VTNE - Veterinary Technician National Examination Practice Test

VTNE Diagnostic Imaging Techniques 5