Terminal valve of sapheno-femoral junction: a comparative assessment between pre-operative color-duplex ultrasound and intra-operative evaluation

Abstract

According to literature data, up to 59% of incompetent great saphenous veins (GSV) have no reflux at the terminal valve (TV) of the saphenofemoral junction (SFJ). The aim was to compare color duplex ultrasound (CDU) investigation and direct intra-operative assessment of competence of the TV at SFJ. A prospective comparative study was performed on 28 patients, who consecutively presented for surgical intervention for their primary varicose veins of the lower limbs with GSV incompetence. CDU assessment was performed pre-operatively to define GSV and SFJ terminal valve morphology and hemodynamics. Under local anesthesia these patients underwent SFJ disconnection (crossectomy) and segmental inverted saphenous stripping of the incompetent GSV tract + phlebectomy of the varicose tributaries. SFJ disconnection was performed in four stages in an ascending fashion: I) division of GSV below the lower SFJ tributaries, II) disconnection of lower SFJ tributaries, III) disconnection of upper tributaries, IV) flush to CFV ligature of GSV stump. After the completion of stage I, the SFJ stump was opened and kept open when needed throughout the subsequent stages, in order to highlight any possible blood leak through the SFJ stump. To highlight intraoperative blood leak from SFJ stump visual observation was carried out both during respiration and when performing Valsalva maneuver and manual compression of homolateral iliac fossa. As to pre-operative CDU all limbs showed GSV reflux and they were divided in two groups according to TV competence (group A) or incompetence (group B). Group A comprised 18 patients (6 M and 12 F), mean age 50.6 years. Group B included 10 patients (4 M and 6 F), mean age 54.8 years. Mean calibre of GSV at proximal/mid thigh was 6.4 mm in group A and 7.8 in group B. Concerning the intra-operative findings: in the group A, 5 patients had blood leak in the SFJ stump after stage I, 4 patients showed blood leak after stage II. After completion of stage III, only one severely obese patient had persistent reflux, whereas 17 patients had no reflux. Conversely the 10 patients from group B had reflux within GSV stump throughout the 3 stages. CDU pre-operative assessment matches intra-operative findings with regards to GSV TV competence/incompetence, with a good overall accuracy (27/28-94%). Different SFJ retrograde flow patterns should be elicited through CDU investigation. Obese patients need a more thorough CDU examination to avoid false negatives.

Keywords

• terminal valve, duplex ultrasound, intra-operative assessment, great saphenous vein.