PRE AND POSTOPERATIVE CONTRIBUTION OF DUP LEX SCAN IN SUPERFICIAL VENOUS SURGERY OF THE POPLITEAL FOSSA

Aims of the study : Does preoperative Duplex Scan (DS) allow to determ ine anatomy of the ending of the short saphenous vein (SSV), gastrocne mius vein (GV) and reflux in popliteal vein (PV). SSV and GV. postoper ative DS was performed to detect deep vein thrombosis (DVT) and GV thr ombosis Material and methods, From June 94 to November 95 one hundred and eighty lower limbs operated fur SSV were included consecutively an d prospectively. Mean age in these 154 patients was 52 yr (24-80) with a sex ratio 4F/1M. An anatomical classification was previously define d. Type A : separate termination of SSV and GV : Type B: common ostium of SSV anti GV in the popliteal vein: Type C: common trunk of the SSV and GV: Type D: Others. Forty-eight limbs (26.10 %) had ligation of G V : 21 (11.10 %) for reflux and 27 (16 %) for anatomical or surgical r easons. Ten type A with GV reflux (10/31 = 32 %) were not treated. Eig hty two patients (45 %) received preventive low molecular weight hepar in (LMWH) treatment including the 48 limbs whose GV were ligated. Resu lts. Anatomical correlation between DS and surgery findings were calcu lated. Positive predictive values of DS in the different types were: A . 77 % : B, 68 % : C, 90 %: D, 79 %. That gave a global predictive val ue of 80 %. Two limited DVT were identified in Eroup B by postoperativ e DS (2/10 = 1.1 %), These two patients had complete recanalization of PV without reflux. In the group of limbs which had ligation of GV we identified 37.5 % of GV thrombosis. In the group without ligation of G V we found 3 % of GV thrombosis. Conclusion: Duplex scanning appears t o be the investigation of choice before surgery for superficial vein i ncompetence in the popliteal fossa. It is a reliable investigation to determine termination patterns of SSV and GV (80 Ck). It brings to the surgeon essential information which helps in the management of surgic al procedure and particularly to ligation of gastrocnemius veins. But at this time then is no consensus on this paint. The occurrence of DVT after SSV surgery including GV ligation was very low, Two questions r emain : - is anticoagulation necessary in all patients or selective af ter surgery of the SSV ? - is Duplex Scan mandatory during postoperati ve monitoring? On the basis of this study, one recommendation can be m ade: A routine postoperative DS is necessary after ligation of the GV or when the dissection of the popliteal fossa has been extensive (Type D).