Clinical and angiographic long-term follow-up of completely coiled intracranial aneurysms using endovascular technique

Object. The anatomical evolution and clinical outcome of completely coiled intracranial aneurysms after endovascular embolization have rarely been studied separately. From their prospective database, the authors reviewed follow-up angiography and clinical outcome of 87 patients whose aneurysms were designated as 100% obliterated on immediate postembolization angiography. Methods. Ninety-one aneurysms ( 56 ruptured and 35 unruptured) in 87 patients were included in this study. Clinical outcome was evaluated using the Glasgow Outcome Scale. Follow-up angiographic findings were assessed and categorized as 1 of the following: no recanalization, recanalization with a neck remnant, or recanalization with a body remnant. For statistical analysis, the recanalization rate was correlated with: clinical presentation; the largest aneurysm diameter, aneurysm neck size, and dome-to-neck ratio; aneurysm location; and use of special techniques such as usage of a surface modified coil, balloon remodeling technique, or stent. Results. At the latest clinical evaluation ( mean 34.3 months), 81 (93.1%) of the 87 patients ( 91 aneurysms) had good clinical outcomes ( Glasgow Outcome Scale Score 5). The procedure-related morbidity rate ( permanent neurological deficit) was 2.3% ( 2 of 87), and there were no procedure-related deaths. On the latest follow-up angiography ( mean 26.4 months), the recanalization rate was 26.4% ( 24 of 91 aneurysms): 16 (17.6%) with neck remnants and 8 (8.8%) with body remnants. The neck size of the recanalized aneurysms was statistically significantly larger than that of the nonrecanalized aneurysms ( p = 0.006), and aneurysms with wide necks (= 4 mm) had a higher recanalization rate than those with a narrow neck (< 4 mm) ( p = 0.002). There was no bleeding after endovascular treatment during the follow-up period. Conclusions. Completely coiled aneurysms after endovascular embolization demonstrated good clinical outcome, and there was no bleeding episode after endovascular treatment; however, there was a relatively high recanalization rate. (DOI: 10.3171/2008.12.JNS08768)