Spontaneous occlusion of the cerebral arteriovenous malformations

Spontaneous occlusion of arteriovenous malformations (AVM), characterized by complete disappearance of the AVM nidus and early venous drainage, and is a rare. The frequency of this phenomenon varied from 0.1 to 1.3 %. We analyzed two cases of spontaneous occlusion of cerebral AVMs with a non-hemorrhagic debut after 3 and 13 years in women aged 28 and 40 years, respectively. In both cases AVM was diagnosed during routine neuroimaging because of headache. Both patients had superficial small malformations. After discussing the risks of surgical treatment, both patients refused to perform any intervention. Scheduled angiography was performed 3 years after the diagnosis to follow-up the course of the disease and revealed complete disappearance of the AVM. Another patient noted persistent regression of headache after 3 years. Follow-up angiography was performed 13 years after diagnosis and confirmed spontaneous occlusion of the AVM. Given the data on the recurrence of the disease after spontaneous occlusion, such patients require long-term follow-up. When an AVM ruptures, hemodynamic changes may explain the thrombosis of the malformation, but the mechanisms of spontaneous occlusion in non-ruptured AVM remain unclear.