CAMRT Imaging Equipment and QC Questions and Answers 2

Question 1

Annual QC testing shows the X-ray tube HVL is below acceptable minimum. What does this indicate?

Accepted Answer

Insufficient beam filtration increasing patient skin dose

Answer

Low HVL indicates inadequate filtration, allowing too many low-energy photons that increase skin dose.

Question 2

What is the purpose of collimator light-to-radiation field alignment testing?

Accepted Answer

Ensure the light field accurately represents the irradiated area

Answer

Alignment testing verifies the collimator light accurately indicates X-ray field boundaries.

Question 3

A fluoroscopy unit ABC is increasing kVp beyond limits. What is the likely cause?

Accepted Answer

Degraded image intensifier input phosphor

Answer

II input phosphor degradation reduces conversion efficiency, causing ABC to compensate by increasing technique.

Question 4

How should the anode heel effect be utilized in clinical practice?

Accepted Answer

Higher intensity on cathode side; position thicker body parts toward cathode

Answer

Greater intensity on the cathode side due to self-absorption in the anode. Thicker parts go toward the cathode.

Question 5

CT QC shows water measures consistently +8 HU instead of 0. What is the significance?

Accepted Answer

Calibration drift affecting diagnostic accuracy; recalibration needed

Answer

Water accuracy should be 0 plus or minus 4 HU. +8 HU indicates systematic drift.

CAMRT - Canadian Association of Medical Radiation Technologists Practice Test