Treatment for veins over about 2 mm in diameter with liquid sclerotherapy becomes less successful with enlarging vein size since the liquid sclerosant is diluted very rapidly by blood as the vein size increases. A technique of generating a foam by mixing a liquid sclerosant with a gas allows injection of small amounts of a foam into abnormal veins. The foam briefly displaces the blood inside the treated veins allowing the sclerosant component of the foam to come into contact with the cells lining the vein without dilution by the blood.

Foam sclerotherapy has proven to be remarkable for treating veins which previously could not be treated very effectively and it also provides another option to more invasive procedures for some patients. We have extensive experience with foam sclerotherapy for treating varicose veins as well as for treatment of very complex varicose veins and venous malformations (abnormal masses of veins present at birth which may enlarge considerably later in life). We use Asclera or Sotradecol and sterile carbon dioxide gas to make the foam which we use.