Quality Control & Assurance Flashcards

Which QC test is performed to evaluate the accuracy of the radiographic timer?

Answer: Spinning top test

The spinning top test evaluates timer accuracy in single-phase or three-phase generators by counting the number of dots or arc produced during a timed exposure. Digital systems require a synchronous spinning top or electronic timer test.

The purpose of performing a sensitometric strip in film-based radiography QC is to:

Answer: Evaluate processor performance by measuring film base-plus-fog, speed, and contrast indices

Sensitometry monitors film processor performance by measuring base-plus-fog (Dmin), speed index (SI), and contrast index (CI) from a standardized sensitometric strip. Deviations indicate processor drift requiring maintenance.

In computed radiography (CR), the erasure cycle of the imaging plate is performed to:

Answer: Remove residual latent image from a previous exposure

The erasure cycle (flooding with intense white light) removes residual latent image trapped in the phosphor crystals of the imaging plate, preventing ghost images from appearing on subsequent exposures.

A lead apron QC program should include which of the following tests performed at least annually?

Answer: Fluoroscopic or radiographic inspection for cracks or defects

Lead aprons must be inspected fluoroscopically or radiographically at least annually (and after suspected damage) to detect cracks, voids, or separation in the lead shielding that would reduce protective effectiveness.

Which phantom is most commonly used for QC testing of fluoroscopic image intensifier systems?

Answer: Leeds TO.16 or RMI 156 fluoroscopic phantom

Fluoroscopic QC phantoms such as the Leeds TO.16 or RMI 156 contain test patterns (resolution, contrast, line pairs) used to assess image intensifier resolution, contrast, and distortion.

Automatic exposure control (AEC) QC testing evaluates:

Answer: Consistency of mAs output across different anatomical part thicknesses

AEC QC testing verifies that the system delivers consistent, appropriate exposure across different thicknesses and at different density settings. The AEC should maintain consistent optical density/detector dose regardless of patient thickness.