Dynamic MR Digital Subtraction Angiography

reference standard for the diagnosis, assessment, and management of pial brain arteriovenous malformations (AVMs). The purpose of this study was to develop an MR angiographic tech-nique that produces dynamic images comparable to those provided by CCA and to apply the technique to the investigation of pial brain AVMs. METHODS: Twenty patients with brain AVMs referred for stereotactic radiosurgery were recruited. All patients had CCA performed on a 1.5-T superconducting system. Sixty images were obtained at a rate of one image per second. Slices were orientated to produce Towne, lateral, and anteroposterior projections. A set of mask images was taken and then a series during the passage of a bolus of contrast material. MR examinations were assessed indepen-dently by neuroradiologists blinded to the conventional catheter angiographic findings. RESULTS: The nidus of the AVMs was depicted in 19 of the 20 patients, and correlation with CCA was excellent for measurements of maximum diameter. Venous drainage was cor-rectly assessed in 18 of 19 cases. CONCLUSION: MR digital subtraction angiography shows promise as a noninvasive, dy-namic angiographic tool for planning stereotactic radiosurgery of AVMs already delineated b