An assessment of long saphenous venography to evaluate the saphenous vein for femoropopliteal bypass.

A long saphenous venogram was performed on a consecutive series of 42 patients (5 bilateral) though in 4 the vein was not satisfactorily demonstrated. In all cases the long saphenous vein was dissected out and its suitability for use for a femoropopliteal bypass compared to the radiological findings. Eleven veins were unusable for a bypass and radiologically these were narrower (mean diameter 2.8 mm) than the veins which functioned satisfactorily (mean diameter 5.0 mm), and had more tributaries (mean 5) than the suitable veins (mean 2). Preoperative venography is a useful technique to identify veins that will be unsuitable for a femoropopliteal bypass and thereby save an unnecessary dissection.