PURPOSE: In patients with perimedullary arteriovenous fistula (AVF) with subarachnoid hemorrhage (SAH), knowledge of lesion location is necessary to select the appropriate approach for catheter spinal angiography. We evaluated the utility of 3-dimensional (3D) fast imaging with steady-state precession (FISP) sequence for detecting type 1 perimedullary AVF with SAH. MATERIALS AND METHODS: We evaluated 4 patients (2 men, 2 women, aged 53 to 68 years, mean age, 59.25 years) with type 1 perimedullary AVF who presented with SAH and underwent conventional spin-echo MR and contrast-enhanced 3D FISP imaging. Two neuroradiologists assessed detection of vascular lesions and delineation of their relationships to the adjacent vessels. Catheter angiography was used as the reference standard and compared with the MR findings. RESULTS: Perimedullary AVF was located at the medullocervical junction in 2 patients, cervical spine in one, and thoracic spine in one. For all patients, use of contrast-enhanced 3D FISP in addition to conventional MR imaging improved lesion detection and delineation of the relationship between the lesion and surrounding vessels. CONCLUSION: Contrast-enhanced 3D FISP imaging was useful for detecting and delineating type 1 perimedullary AVF with SAH.