Radiography Exam Digital Radiography and PACS 2

Question 1

In digital radiography, 'exposure creep' refers to:

Accepted Answer

A gradual increase in patient exposure over time because digital processing masks overexposure by adjusting image brightness automatically

Answer

Exposure creep occurs when radiographers gradually increase mAs over time because the digital processing corrects for overexposure, masking the fact that patients are receiving excessive dose.

Question 2

Which type of artifact in CR imaging appears as a faint previous image superimposed on the current image?

Accepted Answer

Ghost artifact (residual image artifact)

Answer

Ghost artifacts occur in CR when the PSP plate was not completely erased after the previous exposure — residual electrons release during the next scan, creating a faint superimposed image from the previous study.

Question 3

The image matrix size in digital radiography refers to:

Accepted Answer

The number of pixels arranged in rows and columns that make up the digital image

Answer

The image matrix defines how many pixels are arranged in rows × columns to form the digital image — a larger matrix (more pixels) means higher spatial resolution.

Question 4

In a PACS environment, the RIS (Radiology Information System) primarily manages:

Accepted Answer

Patient scheduling, order management, and radiology report generation

Answer

The RIS manages the administrative and workflow functions of the radiology department: scheduling, patient demographics, orders, billing, and report management — it interfaces with PACS for complete workflow.

Question 5

What is the primary difference between lossy and lossless image compression in medical imaging?

Accepted Answer

Lossy compression permanently discards some image data (irreversible), while lossless compression preserves all original data (reversible)

Answer

Lossy compression (e.g., JPEG) permanently discards image data to achieve smaller file sizes, while lossless compression (e.g., JPEG 2000 lossless, RLE) preserves all original data perfectly.

Radiography Exam Practice Test

Radiography Exam Practice Test

Radiography Exam Digital Radiography and PACS 2