Does treatment with N-butyl cyaniOacrylate embolizationprotect against hemorrhage in cerebral arteriovenous malformations?

Objective: To assess the role of this procedure to prevent hemorrhage in cerebral arteriovenous malformations (cAVM). Method: Between 1992 and 2000, we studied 104 patients submitted to emboliza- tion as the main treatment. Patients were followed until hemorrhage or death. Results: Follow-up ranged from 1.6 months to 8 years. The most frequent presentations were hemorrhage (50%) and seizures (38%). In addition, 40% were small ( 2/3 in 36%; complete in 5%. The risk of death was 1%/year, and of bleed- ing, 5.4%/year. Presentation with hemorrhage and low obliteration rate were the main factors associated with hemorrhage. Conclusion: cAVM embolization provides limited protection against hemorrhage with obliteration rates below 2/3. Presentation with hemorrhage is the main factor for predicting hemorrhage. Cerebral arteriovenous malformations (cAVM) are characterized by a plexus of histologically undif- ferentiated vessels in which veins and arteries are directly connected without the usual intervening capillary network. These congenital lesions usual- ly affect otherwise healthy individuals, and are most often diagnosed by the age of 40 years. The usual symptoms are hemorrhage (about 50% of the cases), seizures (30%), headaches (20%), progres- sive neurological deficit (5%), and other less com- mon presentations (5%) 1 . The risk of hemorrhage varies from 2 to 4% per year, and may reach 18%