MEST: Modified electrosclerotherapy to treat AVM (Extracranial Arterio-venous malformations). Better than BEST

Arteriovenous Malformations (AVM) can present themselves in an ample clinical spectrum. They worsen over time, creating local complications such as ulceration, destruction, infection, pain, and severe bleeding. Small focal AVMs can effectively be cured by surgery and/or endovascular techniques, whereas larger ones are of difficult management. Accordingly, S3 AVMs (according to SECg staging) are particularly troublesome. Here, endovascular treatment is only episodically curative while surgery leads to significant structural and functional damage. Electrochemotherapy is an established means to manage selected neoplasms. Recently it was successfully used to treat sclerotherapy-resistant or extensive low-flow vascular malformations (electrosclerotherapy, EST). EST was only anectodically tried with AVMs. A conventional EST is unlikely to effectively have an AVM responding. We conceived the Modified EST (MEST) protocol and started a pilot study. Modification of conventional EST was done by administering bleomycin locally, under ultrasound guidance, in the tissues around the nidus. After 8 min, electroporation was started and covered the entire involved area. MEST was adopted in 10 patients with S3 AVMs of the cervicofacial region. Most patients received 2 sessions of MEST. The response was significant, and the patients all had a complete or near-complete reduction in the size of the AVM. Excellent aesthetic results were achieved. On follow-up imaging the AVMs were not detectable. Side effects were minor and easily managed. Results were stable. The results of the present study suggest that MEST may be the treatment of choice in selected AVMs. However, a longer follow-up is needed to further evaluate the risk of recurrence.