Treatment of angiomas with sclerosing injection of hydroxypolyethoxydodecan. The authors discuss the indications for hydroxypolyethoxydodecan in the sclerosing treatment of angiomas, with particular reference to cavernous, venous, and evolutive angiomas (ie, immature angiomas that fail to involute by eight to ten months). Moreover, the sclerosing agent may be employed, in connection with embolization and subsequent surgery, in arteriovenous angiomas with a relevant cutaneous-subcutaneous development. The authors have successfully used the "interstitial" sclerosing technique, according to Andrews' method. This technique involves interstitial injections to obtain the sclerosis of the thin threads of fibrous tissue stroma between the blood vessels. The sclerosing therapy may cause the complete regression of "low flow" angiomas or, at least, a partial reduction that simplifies the ensuing surgical excision. In the case of partial regression of the angioma obtained with the sclerosing therapy, the surgery of the remaining angioma causes a lesser degree of bleeding (especially in areas that do not particularly lend themselves to surgical exploration, ie, the oral cavity); an increased reliability in the radicality of the intervention (due also to the reduced size of the lesion); and better results from an aesthetic-functional point of view. 