A patient who had previously had an ilio-femoral bypass presented with a growing swelling in his left groin. He had noticed this after lifting a heavy object
Ultrasound of the lump revealed a round echogenic structure which was consistent with the graft. Around this was a hypoechoic, irregular collection which was traced along the path of the graft. The mass was seen to pulsate.
Color Doppler revealed pulsatile flow both through the graft (as expected) and outside the graft which was traced to the distal anastomosis site. Flow was seen in the femoral artery distal to the anastomosis (not shown).
Collections around the anastomosis site can be haematoma, abscesses or leaks / false aneurysms. Color Doppler interrogation is important to distinguish between these. Mirror image artifact can cause color signal to appear outside the graft lumen, due to reflection from the echogenic graft, and will always appear deeper to the mirroring surface (away from the probe), regardless of the angle of insonation. True color signal will have an anatomically consistent site, independent of the position of the probe.
There is controversy regarding the relative accuracy of ultrasound versus CT to detect leaks (particularly for endovascular graft follow up).