Diagnostic Imaging Techniques Flashcards
7 cards from real VTNE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Diagnostic Imaging Techniques flashcards as text
In fluoroscopy, the unit of patient radiation dose most commonly monitored in real time is:
Answer: Air kerma (Gy)
Air kerma measured in Gray (Gy) is the standard real-time dose metric in fluoroscopy, often tracked at the reference point to estimate patient skin dose.
Which MRI sequence produces images where fluid appears bright (hyperintense)?
Answer: T2-weighted
On T2-weighted sequences, fluids have long T2 relaxation times and therefore appear bright, making them useful for detecting edema, effusions, and CSF.
A cat presents with suspected hypertrophic cardiomyopathy. Which echocardiographic measurement is MOST important to obtain?
Answer: Left ventricular free wall thickness in diastole
HCM is diagnosed by increased left ventricular wall thickness (≥6 mm in diastole in cats) measured in the absence of other causes of hypertrophy.
What is the purpose of using a grid in radiography?
Answer: To reduce scatter radiation reaching the image receptor
A grid consists of lead strips that absorb scattered radiation produced in the patient, improving image contrast by reducing the scatter fog reaching the detector.
During abdominal ultrasound, the spleen of a dog appears diffusely hyperechoic compared to the liver. This finding is MOST consistent with:
Answer: Nodular hyperplasia or diffuse infiltrative disease
A diffusely hyperechoic spleen relative to the liver is abnormal and most often associated with nodular hyperplasia, extramedullary hematopoiesis, or infiltrative neoplasia.
Which positioning aid is MOST appropriate for keeping a patient's limb in true lateral for an orthopedic radiograph?
Answer: Sandbags
Sandbags provide firm, moldable support to maintain limb position without personnel entering the primary beam, complying with ALARA principles.
The Mach effect artifact on a radiograph appears as a dark line at the interface of two structures of different opacity. It is caused by:
Answer: Edge enhancement by the human visual system
The Mach effect is a perceptual phenomenon where the human visual system exaggerates contrast at edges, creating an apparent dark band at density interfaces.