Blocking the Saphenofemoral Junction During Ultrasound-Guided Foam Sclerotherapy - Assessment of a Presumed Safety-measure Procedure

Objectives: Ultrasound-guided foam sclerotherapy (UGFS) is a technique in which a mixture of sclerosing drug and gas is used to treat varicose veins. Several authors have demonstrated transient systemic effects after UGFS. These effects are not well understood but probably originate from a systemic distribution of the sclerosing foam. Therefore, safety measures have been developed to prevent foam from flowing into the deep venous system. The aim of the study is to evaluate whether blockage of the saphenofemoral (SF) junction by either manual compression or surgical ligation prevents microbubbles from leaking into the deep venous circulation. Methods: To detect the distribution of microbubbles, radioactive pertechnetate ((99m)TcO(4)(-)) was added to the foam solution. Initially, in vitro trials were performed in the laboratory to investigate the effect of (99m)Tc on foam stability. The time taken for foam to liquefy was measured for foam alone and for the mixture with (99m)Tc. In subsequent research, eight varicose great saphenous veins (GSVs) were treated by UGFS. In three patients, this treatment was preceded by surgical ligation of the SF junction. In three patients, the groin was manually compressed during UGFS. In two patients, UGFS was performed without compression of the groin. Results: In vitro, (99m)Tc did not influence foam stability; after 2.6 min all foam had reduced to Liquid, regardless of whether (99m)Tc had been added or not. In vivo trials showed that all patients showed a decrease in the cumulative amount of (99m)Tc detected in the GSV following polidocanol-(99m)Tc mixture injection. However, the decrease of radioactivity was slightly reduced when compression or ligation of the SF junction was performed. Conclusions: Blocking the SF junction during UGFS using either manual compression or ligation does not prevent, but may reduce the flow of foam into the femoral vein.