ARRT Image Acquisition and Evaluation 2

Question 1

Which exposure indicator value range is typically considered acceptable on most CR and DR systems?

Accepted Answer

300–600

Answer

Most CR/DR systems target an exposure indicator (EI) of approximately 300–600, though exact ranges vary by vendor.

Question 2

A radiograph of the lumbar spine shows the vertebral endplates are not parallel to the beam. Which artifact or error does this represent?

Accepted Answer

Beam alignment error

Answer

Tilting the tube or patient so endplates are not perpendicular to the central ray causes beam alignment error, projecting structures as distorted.

Question 3

The anode heel effect causes the intensity of the X-ray beam to be greatest near which side of the tube?

Accepted Answer

Cathode side

Answer

X-ray intensity is greatest on the cathode side because the anode's beveled surface absorbs more photons on the anode side.

Question 4

When reviewing a chest radiograph, you notice the left hemidiaphragm appears higher than expected. What is the most likely technical cause if the image is not rotated?

Accepted Answer

Scoliosis or elevated diaphragm on that side

Answer

Without rotation, an elevated hemidiaphragm on one side suggests a true anatomical or pathological elevation, not a positioning error.

Question 5

Which factor most directly controls the optical density (brightness) on a digital radiograph?

Accepted Answer

mAs

Answer

mAs controls the number of photons produced and thus the exposure reaching the detector, directly determining image brightness (exposure level).

ARRT - American Registry of Radiologic Technologists Practice Test

ARRT - American Registry of Radiologic Technologists Practice Test

ARRT Image Acquisition and Evaluation 2