[The role of magnetic resonance angiography in the follow-up of intracranial arteriovenous malformations treated by an intravascular approach].

The purpose of our work was to measure the accuracy and reliability of MR-Angiography in the study and follow-up of intracranial arteriovenous malformations, and in particular to evaluate the results of endovascular treatment. Over an 18-month period 4 patients with such malformations were examined by MR-Angiography. There was an angioma of the corpus callosum, a left parieto-rolandic angioma, a posterior thalamic angioma and a cerebellar angioma. All examinations were performed with a Magneton-Impact 1 Tesla machine (Siemens, Erlangen, Germany), using a head coil, MR-Angiography with time-of-flight sequences and differential arterial and venous saturations. Each patient was examined by MR-Angiography first at the beginning of treatment, then when ambulatory after embolization. The morphological study applied to the afferent vessels, the nidus and the efferent veins. MR-Angiography proved to be very good in identifying the arteries feeding the malformation, and this made it easier to evaluate the reduction of their input after treatment, without having recourse to any arteriography. Beside, analysis of the nidus was facilitated by the judicious arrangement of arterial and venous saturations. In fact, the systematic use of MR-Angiography in the follow-up of intracranial arteriovenous malformations makes it possible to measure, with full reliability, the efficacy of the endovascular treatment under conditions of comfort unequalled in these out-patients, and selective angiography sequences need to be performed only during therapeutic phases.