Purpose: To evaluate the stability of aneurysm occlusion over time, the need for additional treatments, and the long-term clinical outcome of patients, with emphasis on late recurrences of bleeding.
Materials and methods: The records of 160 patients with aneurysmal subarachnoid hemorrhage who were treated with coils were retrospectively reviewed. Follow-up angiography was performed 6 and 18 months after coil placement, and the results were classified as complete, near complete, and incomplete occlusion.
Results: Six (4%) of the 160 patients experienced procedural mortality or dependency. After a mean follow-up of 36 months, 134 (84%) patients had a good outcome. Outcome was independent of aneurysm size and location and timing of treatment. Reopening of the aneurysm occurred exclusively during the first 6 months after coil placement, mainly in aneurysms larger than 15 mm. Between 6 and 18 months, no change in aneurysm occlusion was observed. Additional coil placement was performed in 15 (9%) patients. After this second coil placement, nine (7%) aneurysms were still incompletely occluded. Additional therapy was performed in eight (5%) patients. Two recurrences of bleeding were observed in two incompletely occluded large aneurysms. No recurrences of bleeding occurred in patients with completely or near completely occluded aneurysms.
Conclusion: Coil placement is an effective and safe treatment strategy for patients with aneurysmal subarachnoid hemorrhage. If aneurysm occlusion is sufficient at 6 months, the yield of further follow-up angiography is very low.