Atypical Color Doppler Findings Related to Remote Lower-Extremity Traumatic Injury

Abstract

Introduction Ultrasound artifacts can be misleading. This case demonstrates an unusual color Doppler artifact encountered while performing a lower-extremity venous evaluation. This color Doppler artifact was so unique that initially it was thought to be an incidental vascular finding. Case Study A 46-yr-old military veteran was seen in our noninvasive vascular laboratory for a lower-extremity venous evaluation because of left lower-extremity edema. He gave a history of chronic left lower-extremity pain from a war injury to his anterior left calf. An abscess developed 1.5 yr ago after he received whirlpool therapy. When the transducer was placed on the injury site, a large portion of the abscess filled with mosaic color that appeared to originate from the anterior portion. This color occurred without transducer movement. The appearance was similar to an arteriovenous fistula, which was suspected because of varicosities in the vicinity. However, pulsed Doppler revealed artifactual noise. Conclusion It was suspected that this was an impressive, atypical color Doppler reverberation artifact. The patient's tibiofibula radiographs showed pieces of shrapnel throughout the abscess. We hypothesize that the artifact was created by acceleration of the sound waves through the fluid in the large abscess with resonation between fragments of shrapnel. This is an example of a color Doppler artifact making it appear that there is flow in a location where there is none.