Dropout bands caused by annular ring malfunction can appear at a depth.

• A. A dropout band at a depth
• B. Across all depths
• C. A cross-hatch band
• D. No dropout

Answer: (A)

Dropout bands from an annular ring malfunction arise from a localized, fixed defect in the imaging system. Because the fault sits in a specific region of the detector or transducer, the corrupted signal maps to a particular depth plane when the image is reconstructed. In depth-resolved imaging, that means you’ll see a dropout band at that specific depth, not across every depth. The artifact isn’t a grid-like (cross-hatch) pattern, and it isn’t spread through all depths, since the defect’s influence is tied to one depth corresponding to where the faulty ring projects.