Arteriovenous malformation nidus catheterization with a flow-directed catheter at times can be difficult owing to tortuosity of the intracranial vasculature and distal location of the nidus. Since January 1995, hydrophilic wire has been used in conjunction with the 1.8F flow-directed microcatheter in over 150 vessel embolizations with cyanoacrylate glue for brain and spinal arteriovenous malformations at our institution. This technique has improved our success rate in achieving superselective catheterization of the nidus and has shortened the overall procedure time. To date, only one complication has occurred that was directly related to wire manipulation.