An investigation on the influence of glycerin on sclerosant foam stability

Abstract

Foam sclerotherapy is an increasingly popular modality in the treatment of varicose veins. Foam stability varies according to foam composition, volume and injection technique. A disposable plastic connector was used to create foam from 0.50% sodium tetradecyl sulphate (STS) mixed with varying volumes of glycerin. As a measure of foam stability, the half liquid time was defined as the time required for half of the original volume of sclerosing solution to settle. Three recordings were determined for each of the three mixtures of sclerosant foam. The time for sclerosing solution to settle to half of its initial volume was found to be 89 seconds for 0.50% STS alone, 117.7 seconds with the addition of 0.1 mL of 72% glycerin, and 114.7 seconds with the addition of 0.2 mL of 72% glycerin. The small volumes of glycerin added to STS prolonged the half liquid time of STS foam up to 35%. As glycerin alone is unable to be foamed with the double-syringe system technique there may be a point at which further addition of glycerin has a negative effect on the half-life of foam.