[TOF-MR angiography in radiotherapy treated cerebral arteriovenous malformations]

Intracerebral arteriovenous malformations represent congenital anomalies with an arteriovenous shunt (nidus). The therapeutic goal is to eliminate the risk of bleeding and to improve the clinical symptoms. The exact localization of the nidus and the identification of the feeding arteries are critical for therapy planning. Up to now conventional brain angiograms have been used for treatment planning and for the assessment of therapy response. We studied whether 3D time-of-flight (TOF) MR angiography can be used for therapy planning and monitoring. MRI and TOF-MRA studies of 28 patients undergoing radiotherapy were evaluated. They were compared to conventional angiography to assess the MRA study. A Correct identification of the arterial feeder and the nidus was possible in about 75% of the patients. In combination with the MRI study, an important 3D dataset for treatment planning could be obtained that includes therapeutically relevant information on the localization and spatial structure of the AVM as well as the adjacent brain tissue. As a noninvasive technique, close-meshed follow-up studies could be performed with MRA.