VENOUS HEMODYNAMICS AND THE OCCURRENCE OF LEG EDEMA IN PATIENTS WITH POPLITEAL ANEURYSM

Objectives: To see whether popliteal aneurysms cause venous obstructio n and to investigate leg oedema and DVT following repair. Design: Pros pective open clinical study. Setting: University Department of Surgery . Materials: 8 patients undergoing popliteal aneurysm repair in 9 legs (I bilateral repair). Chief outcome measures: CT and plethysmographic evidence of vein compression, the occurrence of postoperative leg oed ema and phlebographic evidence of deep venous thrombosis (DVT). Main r esults: Preoperative CT investigation showed that the aneurysm compres sed the popliteal vein in 6/9 limbs where surgery was planned and in 9 /10 limbs with popliteal aneurysms (patent or occluded) of >2cm diamet er (p <0.01). However, on the CT image, increased collateral network c ould be observed and most patients had normal venous drainage prior to , operation as assessed by air plethysmography. Postoperatively, leg v olume was measured by the formula of a truncated cone. Following vascu lar reconstruction leg volume increased by 23%. Except for one patient with a confirmed DVT preoperatively, postoperative venous congestion and DVT was not observed in the operated leg as assessed by phlebograp hy and plethysmography. Conclusions: Popliteal artery aneurysms >2cm d iameter usually compress and dislocate the popliteal vein prior to ope ration. However, sufficient venous drainage is maintained, possibly be cause of an increased collateral venous network. Disruption of lymph c hannels with secondary lymphoedema is probably the most important mech anism behind the leg swelling observed in patients following popliteal aneurysm repair.