Real time B-mode mapping of the greater saphenous vein.

Real time ultrasound mapping of the greater saphenous vein (GSV) was performed in 30 consecutive patients admitted for in situ femoro-crural revascularisation. The overall accuracy in predicting the adequacy of the GSV for in situ bypass was 90%. The predictive value of finding the vein usable was 96%, whereas the predictive value of judging the vein inadequate was 50%. The scanning procedure provided morphologic information about the GSVs, including size, tributaries, varicosities, and double segments, which may prevent unnecessary dissection and may further shorten the duration of surgery. In our opinion the technique is sufficiently accurate to replace phlebography for the routine preoperative assessment of GSV in patients considered for in situ bypass. Veins judged inadequate at scanning, however, should be further evaluated.