Place de la radiochirurgie dans la prise en charge des cavernomes intracrâniens. Revue de la littérature

From a review of the literature dealing with radiosurgery of cavernous malformations, we have analyzed its impact on hemorrhagic risk, epilepsy, histological modifications, morbidity and potential indications of treatment. Radiosurgery could significantly reduce the hemorrhagic risk, in a selected population with a high risk of hemorrhage, after an interval of about 2 years, but cannot provide protection against rebleeding. As for epilepsy related to the lesion, a significant reduction of seizures has been observed in certain cases, with better control in case of recent evolution and simple seizures linked to the site of the vascular malformation. Histologic lesions are vascular fibrosis, fibrinoid necrosis and ferrugination, without good correlation with results of CT scan or MRI. Morbidity of radiosurgery seems higher compared to other diseases with similar doses and target volumes. The rate of transient complications was about 25%, with permanent sequelae in 5 to 10% of patients. This would be due to a radiosensitizing effect of the hemosiderin halo around the lesion. Radiosurgery can be proposed for non-surgical lesions with a high risk of hemorrhage, nevertheless the superiority of the technique over conservative treatment has to be proven. Without long-term prospective studies, the efficiency of RS for cavernomas remains questionable and subject to debate. New imaging methods proving the obstruction of the cavernous malformation are needed.