Anatomic relationship between the popliteal artery and vein: a guide to accurate angiographic puncture.

The anatomic relationship between the popliteal artery and vein means that an arteriovenous fistula can be created when a popliteal artery approach is used for endovascular interventions. To determine the best site for retrograde puncture of the popliteal artery, we studied six cadaveric specimens, CT scans of 31 patients at 280 levels, and 30 plain radiographs of the knee. In the cadaveric specimens, the vessels were enclosed in a common sheath. In 92% of all levels studied on CT, the artery was anterior to the vein (anterolateral in 9%, anteromedial in 43%, strictly anterior in 40%), and more than 25% of the diameter of the artery overlapped the vein in 87% of these levels. However, at the most cranial level analyzed (64 mm above the femorotibial joint space level), such an overlap occurred in only 60%, and the artery was medial in 25%, resulting in a relationship between the artery and the vein that involved less risk of fistula. On radiographic study, the popliteal crease was located above the level of the joint space (considered the most reliable landmark of the popliteal fossa anatomy) in 97% of cases, although the values were scattered (mean, 2.9 +/- 1.5 cm). In order to minimize the risk of creating an arteriovenous fistula, we recommend a skin incision be located 3-4 cm above the joint level as determined by fluoroscopy, and a puncture directed obliquely from caudal to cranial and from medial to lateral.