VSGBI abstracts 15
Method: Thirty patients (primary varicose veins, sapheno-femoral [SFJ] and great saphenous vein [GSV] reflux) undergoing SFJ ligation and stripping were included in the study. 3cm proximal GSV segments harvested before stripping were divided into test and control samples. One percent and 3% STD foam (Tesari) was applied to the vein lumen of test samples for 1, 2 and 5 minutes (n = 5 for each time and STD concentration). Following immediate fixation, sections underwent H&E and specific elastin and collagen staining. Results: One percent and 3% foam caused โค 50% endothelial cell loss after 1 and 2-minute exposure increasing to 80-90% after 5 minutes, although islands of endothelial cells remained visible in all sections. Subendothelial vacuolation (smooth muscle cell damage) only occurred after 5 minutes as did collagen bundle disorganisation. This was minimal, affecting only the inner media. Elastin was unaffected. One percent and 3% STD had similar effects. Foam started to liquify after 90 seconds. Conclusion: Persisting endothelial cells and patchy partial thickness smooth muscle/collagen injury may explain the capacity for recanalisation and high clinical recurrence rates following FS. Further, significant venous injury only occurred after a longer exposure to STD than may occur in vivo.