Hemorrhage in arteriovenous malformations: clinical and anatomic data

Background and purpose. Potential severity of hemorrhage often leads to tre at a cerebral arteriovenous malformation. Consequences can be very various and serious. Our first purpose is to define the different types of hemorrha ge. Our second purpose is to appreciate more precisely individual hemorragi c risk of a cerebral arteriovenous malformation with the study of his angio architecture. We performed a prospective study in order to validate a logis tic model and a classification previously described. Patients and method Front the whale series of 705 patients, 57% (n = 394) s uffered a parenchymal, subarachnoid or ventricular hemorrhage. Logistic mod el and classification of the hemorrhagic risk were prospectively tested on a consecutive population of 78 patients. Comparisons of theorical (calculat ed hemorrhagic risk) and real (hemorrhage or not) were performed by non par ametric tears. Results. Characteristics and clinical consequences of the hemorrhage were a nalyzed. Results of the prospective study confirmed data of the classificat ion and showed a hemorrhage risk increasing with the grade : grade Ia 0 %, grade Ib 30 %, grade II 44 %, grade III 57 %, grade IV 88 %. Conclusion, The study of the angioarchitecture of a cerebral arterio-venous malformation allowed to assess with accuracy his individual hemorrhagic ri sk. However this precision may be improved by the study of other parameters of intracranial arteriovenous malformation.