Brain arteriovenous malformations: Assessment with dynamic MR digital subtraction angiography

BACKGROUND AND PURPOSE: Conventional catheter angiography (CCA) is the curr ent reference standard for the diagnosis, assessment, and management of pia l brain arteriovenous malformations (AVMs), The purpose of this study was t o develop an MR angiographic technique that produces dynamic images compara ble to those provided by CCA and to apply the technique to the investigatio n of pial brain AVMs, METHODS: Twenty patients with brain AVMs referred for stereotactic radiosur gery mere recruited, All patients had CCA performed on a 1.5-T superconduct ing system, Sixty images were obtained at a rate of one image per second, S lices were orientated to produce Towne, lateral, and anteroposterior projec tions. A set of mask images was taken and then a series during the passage of a bolus of contrast material. MR examinations were assessed independentl y by neuroradiologists blinded to the conventional catheter angiographic fi ndings, RESULTS: The nidus of the AVMs was depicted in 19 of the 20 patients, and c orrelation with CCA was excellent for measurements of maximum diameter. Ven ous drainage was correctly assessed in 18 of 19 cases. CONCLUSION: MR digital subtraction angiography shows promise as a noninvasi ve, dynamic angiographic tool for planning stereotactic radiosurgery of AVM s already delineated by catheter angiography, At present, it suffers from t emporal and spatial resolution, which impede the assessment of some brain A VMs.