Acoustic shadowing
Read more:ASE 2026 · Cardiac ultrasound artifacts
Quick reference:↑ Cross-cutting acquisition and artifacts
| View | Any view with calcification, prosthetic material, device leads or dense contrast between the transducer and the region of interest. |
|---|---|
| Timing | Constant through the cycle; the shadow tracks the reflector. |
| Caliper / trace | Not measured: note what lies distal to the reflector and cannot be assessed. |
Example
Correct example
A dark, detail-free zone distal to mitral annular calcification, a sewing ring or a lead is reported as shadowing, and the structures behind it (LA, leaflets, regurgitant jets) are assessed from another window or by TEE.
Common error
Reporting absence of MR, thrombus or vegetation in a region that was shadowed, especially behind a prosthetic mitral valve in apical views.
Effect on interpretation
Shadowing produces false negatives: what cannot be seen is reported as not assessed, not as normal.
Why
A highly reflective interface returns most of the beam, so little energy propagates distally; changing the plane or angle, or TEE, places the region of interest in front of the reflector.