Complex-shaped platinum coils for brain aneurysms: higher packing density, improved biomechanical stability, and midterm angiographic outcome

Abstract

Background and purpose: Five to 60% of coiled brain aneurysms recanalize, generally because of coil compaction. In vitro exclusive use of complex-shaped coils allows better packing of the aneurysmal sac and the neck as compared with helical coils. We report a single-center, prospective study using complex coils. Safety, packing density, and recanalization rate were evaluated.

Materials and methods: Seventy-seven aneurysms were embolized using complex coils alone. Aneurysms had a volume of 265 mm3 (diameter: 7.1+/-3.3 mm) and a neck size of 4.1+/-1.8 mm (range: 1.5-12 mm). Average follow-up available in 31 patients was 10.5+/-7.6 months (range: 3-36 months). Primary angiographic endpoints included aneurysmal recanalization and (re)rupture. Primary adverse events included stroke or death.

Results: Complete or near-complete occlusion was achieved in all of the aneurysms but required balloon assistance in 24.6%. The packing density was computed as 37%+/-13%. No rerupture was observed during the follow-up interval. Recanalization was seen in 4 (12.9%) of 31. Two basilar tip aneurysms underwent a safe and complete recoiling. Periprocedural nondevice-related neurologic deficits were seen in 2 (2.9%) of 69 patients.

Conclusions: The use of complex-shaped coils allows higher packing density, which may improve the recanalization rate. Basilar tip aneurysms remain a challenge.

Figures

Fig 1.

Aneurysm morphometry.

Fig 2.

A, A 74-year-old woman with an asymptomatic wide-neck left middle cerebral artery aneurysm (size: 10 × 10 × 12 mm; neck: 7 mm). B, Balloon-assisted coiling (arrows) with tight filling of the aneurysm and preservation of adjacent displaced M2 branches. C, Postembolization angiogram shows complete occlusion of the aneurysm. D, A 22-month follow-up angiogram shows no aneurysmal recanalization or coil compaction.

Fig 3.

A 62-year-old man with a ruptured wide-neck basilar tip aneurysm (size: 10 × 9 × 8 mm; neck: 6 mm). A and B, Frontal and lateral views, respectively. C and D, Control angiography after complete coiling (packing density: 34.4%). E (right oblique view) and F, 8-month follow-up angiography and recanalization of the posterior, right lateral aspect of the aneurysm corresponding with the maximum hydrodynamic impingement zone in the main axis of the basilar artery; a coil compaction is noted (arrows). G and H Control angiography after recoiling.