Stability of foam in sclerotherapy: differences between sodium tetradecyl sulfate and polidocanol and the type of connector used in the double-syringe system technique.

BACKGROUND: Foam sclerotherapy is an increasingly popular modality in the treatment of varicose veins. Worldwide, the most popular agents used are sodium tetradecyl sulfate (STS) and polidocanol (POL). The double-syringe system technique to make foam out of a sclerosing solution and air has received wide attention for its ease and reproducibility. This study examined the possibility that the relative silicone content of various disposable connectors may affect overall foam stability. We also evaluated the differences in the stability of foam between STS and POL.

MATERIALS AND METHODS: In the first part of the study, one nondisposable stainless steel connector and five disposable plastic connectors were used to create foam from STS 0.50% and air. The procedure was then repeated to produce foam from POL 0.50% and air from each of the six different connector types. As a measure of foam stability, once foam was created with each type of connector, the time required for half of the original volume of sclerosing solution to settle was recorded. In the second part of the study, foam was created with a nondisposable stainless steel connector only and various concentrations of STS and POL. Foam stability was then measured for these different concentrations of sclerosants.

RESULTS: The time for sclerosing solution to settle to half of its initial volume was found to vary according to the specific sclerosant and concentration used, with no statistically significant variation based on connector type.

CONCLUSIONS: The type of connector used in the double-syringe system technique to produce foam for sclerotherapy is not a factor in foam stability. Sclerosing solutions differ in their foaming stability.