AbstractBackgroundThe great saphenous vein is the major superficial vein of the lower limb, and also the most often used as arterial graft material for lower limb revascularization. Prior knowledge of the quality of the vein can guide choice of therapeutic strategy, avoiding surgery that is doomed to failure. Discrepancies between intraoperative findings of the quality of the great saphenous vein and imaging tests are also frequently observed.ObjectivesTo evaluate the diameter of the great saphenous vein using two imaging methods (Duplex Ultrasound and Computed Tomography) and the gold-standard (intraoperative direct measurement of the vein), comparing the results.MethodsProspective, observational study of data obtained during routine medical procedures performed by the Vascular Surgery team.Results41 patients were evaluated, with a 12-month follow-up. 27 (65.85%) were male and mean age was 65.37 years. 19 (46.34%) patients had femoropopliteal grafts and 22 (53.66%) had distal grafts. Preoperative saphenous vein internal diameters measured with the patient supine were on average 16.4% smaller on CT and 33.8% smaller on US than the external diameters measured after intraoperative hydrostatic dilatation. There were no statistical differences in measurements when sex, weight, and height were considered.ConclusionsSaphenous vein diameters were underestimated by preoperative US and CT scans when compared to intraoperative measurements. Thus, in patients undergoing graft planning for revascularization, the choice of conduit should take this data into consideration, so that use of the saphenous vein is not ruled out unnecessarily during planning.