[Spontaneous arteriovenous fistula of the external carotid artery treated by a detachable balloon--a case report].

Spontaneous arterio-venous fistula (AVF) of the external carotid system is very rare. We successfully treated such a case by the detachable balloon method. The patient, a 2-year-and-9-month-old female who has no history of trauma had a pulsating mass at her right retroauricular region six months after birth. On admission to our clinic she was neurologically free except the pulsating mass (2 X 3 cm) with bruit and thrill. Selective right external carotid angiography revealed a high-flow simple AVF from internal maxillary artery to jugular vein. The normal blood flow of both the external and internal carotid system was decreased. Under local anesthesia, non-detachable balloon catheter was inserted to the internal maxillary artery by the transfemoral approach and inflated at the proximal side of the orifice of AVF until the vascular murmur in the neck disappeared. The balloon catheter was then exchanged with a detachable balloon catheter (Debrun, No. 9) which was inflated by silicone (0.4 ml), and was detached successfully. Follow-up angiography 1 year after the treatment revealed no recurrence of the fistula and almost branches of external carotid artery such as middle meningeal artery, occipital artery, superficial temporal artery and facial artery were clearly seen.