Abstract
Objective: Use of a catheter exchange technique for wide-necked large basilar tip aneurysms in which placement of a balloon catheter across the aneurysmal neck is difficult is described.
Case Report: A 71-year-old woman presenting with severe headache and vomiting was diagnosed with a subarachnoid hemorrhage by CT on admission. Preoperative angiography indicated a large saccular aneurysm at the tip of the basilar artery, and coil embolization was performed. As the broad neck of the aneurysm was located between the basilar and left posterior cerebral arteries, a neck remodelling technique was necessary. However, placement of a balloon catheter was extremely complicated, and endovascular treatment failed, despite the use of different kinds of microguidewires and microcatheters on the first attempt. On the second attempt, a catheter exchange technique was used and the balloon catheter was able to be easily positioned. Successful embolization was achieved using the neck remodelling technique.
Technique: First, a soft microcatheter was navigated through the basilar artery to the left posterior cerebral artery using a flexible microguidewire. Tips of the microguidewire and microcatheter were advanced to the distal part of the left posterior cerebral artery for stable positioning. The microguidewire was then exchanged for a long microguidewire, which was advanced into the microcatheter. The microcatheter was then removed over the wire. Next, a balloon catheter was advanced over the long microguidewire and positioned. Finary, coil embolization was achieved safely in the aneurysmal sac using the neck remodelling technique.
Conclusion: A technique to bypass the aneurysmal neck to perform balloon-assisted endovascular treatment of large aneurysms with broad necks in which other methods fail to obtain access distal to the aneurysm was described. For cases in which placement of a balloon catheter is difficult, the catheter exchange technique is considered to be highly effective.
