Classification and Sclerotherapy for Vascular Malformations

Abstract

Venous malformations (VM) are low-flow vascular malformations. Symptomatic venous malformations are much more common than AVMs. The true size of the lesion is best demonstrated by T2-weighted MRI and by direct intralesional contrast injection. There are two major forms or venous malformations: one consisting of clusters of interconnecting venous spaces with minimal or no connections to adjacent normal systemic veins, and another in which the clusters of venous channels communicate freely with dysplastic systemic veins. Surgical treatment may be effective in localized lesions, but often involves excision of surrounding normal tissue, and also has a high rate of recurrence. Venous malformations do not respond to arterial embolization. The most effective interventional management is direct intralesional injection of a scleosant (sclerotherapy). One hundred percent ethanol has been has found to have the lowest recurrence rate of the liquid sclerosants. It produces extreme pain on injection and therefore requires general anesthesia. Because of its neurolytic effect, the injection’s use is generally associated with relatively minor postprocedural pain. Polidocanol and Monoethanolamine oleate (EO) can be diluted with liquid contrast medium. It has the advantage of causing minor discomfort on injection, so that it can be used without a general anesthesia.