Computed Tomography Test Computed Tomography Ultimate 3

Question 1

A patient has a serum creatinine of 2.8 mg/dL. What is the most appropriate action before administering iodinated contrast?

Accepted Answer

Consult with the ordering physician and consider pre-hydration or alternative imaging

Answer

Elevated creatinine indicates impaired renal function; the clinical team should assess the risk-benefit ratio and consider IV hydration or alternative modalities.

Question 2

Which CT technique uses two X-ray tubes operating at different kilovoltage peaks simultaneously?

Accepted Answer

Dual-energy CT

Answer

Dual-energy CT employs two X-ray sources at different kVp settings (e.g., 80 and 140 kVp) to exploit differences in tissue attenuation based on photon energy.

Question 3

What is the role of the 'anti-scatter grid' in CT imaging?

Accepted Answer

It reduces scattered radiation reaching the detectors

Answer

Anti-scatter grids are placed in front of detectors to absorb scattered photons that would otherwise degrade image contrast and quality.

Question 4

Which contrast injection phase best visualizes hepatocellular carcinoma (HCC)?

Accepted Answer

Arterial phase

Answer

HCC is hypervascular and enhances avidly during the arterial phase (approximately 25-35 seconds after injection) when hepatic artery flow predominates.

Question 5

What does ALARA stand for in radiation protection?

Accepted Answer

As Low As Reasonably Achievable

Answer

ALARA is the guiding principle in radiation protection meaning doses should be kept as low as reasonably achievable while maintaining diagnostic image quality.

Computed Tomography Test Practice Test

Computed Tomography Test Practice Test

Computed Tomography Test Computed Tomography Ultimate 3