A long, bright echogenic streak in the CFV that is compressible and moves with venous flow likely indicates what?

A long, bright echogenic streak in the common femoral vein (CFV) that is compressible and moves with venous flow is indicative of a remnant of a recanalized old deep vein thrombosis (DVT). This finding suggests that the original clot has undergone some degree of resolution or recanalization, allowing some blood flow to pass through, which can be observed as a streak that shifts with the dynamics of venous flow.

The echogenicity suggests that the remnant is still echogenic, which is typical for older clots that have organized but have not completely resolved. The compressibility indicates that the structure is not a solid, completely obstructive clot but rather a remnant, allowing for successful venous compression and motion during the evaluation.

Overall, this combination of echogenicity, compressibility, and movement with venous flow is characteristic of a recanalized clot rather than newly formed thrombosis or structural abnormalities like wall thrombus or valve incompetence.