Which artifact is produced when a CR image receptor is not completely erased before the next use?

Which artifact is produced when a CR image receptor is not completely erased before the next use?

• A. Ghost image
• B. Quantum mottle
• C. Radiation fog
• D. Loss of contrast

Answer: (A)

In computed radiography, the imaging plate stores a latent image in the phosphor after exposure, and a dedicated erasure step clears that stored information before the plate is reused. If this erasure is incomplete, some of the previous exposure’s energy remains trapped. When the plate is scanned again, that residual energy is released as the new image is read, creating a faint overlay of the prior anatomy on the new radiograph—a ghost image. This artifact can obscure diagnostic details because it appears in the same region as the original image and repeats with subsequent exposures until the plate is properly erased. Quantum mottle is random graininess from insufficient exposure, radiation fog is general fogging from scatter or stray exposure, and loss of contrast comes from factors that affect tissue separation in the image—not from leftovers of a prior exposure. To prevent ghost images, ensure thorough erasure of the plate between uses and verify the erasure process in the CR workflow.

In computed radiography, the imaging plate stores a latent image in the phosphor after exposure, and a dedicated erasure step clears that stored information before the plate is reused. If this erasure is incomplete, some of the previous exposure’s energy remains trapped. When the plate is scanned again, that residual energy is released as the new image is read, creating a faint overlay of the prior anatomy on the new radiograph—a ghost image. This artifact can obscure diagnostic details because it appears in the same region as the original image and repeats with subsequent exposures until the plate is properly erased.

Quantum mottle is random graininess from insufficient exposure, radiation fog is general fogging from scatter or stray exposure, and loss of contrast comes from factors that affect tissue separation in the image—not from leftovers of a prior exposure. To prevent ghost images, ensure thorough erasure of the plate between uses and verify the erasure process in the CR workflow.