Endosaccular treatment of intracranial aneurysms using matrix coils - Early experience and midterm follow-up

Background and Purpose - The authors report their experience using Matrix coils in the treatment of cerebral aneurysms. Methods - The outcomes of 72 consecutive patients ( 76 aneurysms) who underwent coiling using Matrix coils at our institution were retrospectively analyzed. Results - Seventy-four aneurysms in 70 patients were coiled using Matrix coils ( ranging 3% to 100% by coil length; mean 68.8%). Two patients underwent regular platinum coil embolization after failed Matrix coil placement. Thirty-two (42%) ruptured aneurysms were acutely treated. In 46 aneurysms, Matrix composed > 50% of coil length. Complete aneurysm occlusion was obtained in 13 aneurysms (17.6%), neck remnant in 30 (40.5%), and dome filling in 31 (41.9%). Procedural morbidity and mortality rates were 1.4% and 1.4%, respectively. Angiographic follow-up was obtained in 63.5% ( 47 of 74 aneurysms; average 12.2 months; range 0 to 34). In these 47 angiographically followed aneurysms, the overall recanalization rate was 57.4%. In aneurysms with > 50% Matrix coils, 76.1% had angiographic follow-up ( 35 of 46), and in this group, the overall recanalization rate was 54.3% ( 19 of 35): 25% ( 1 of 4) for very small ( < 5 mm); 33% ( 4 of 12) for small-size ( < 10 mm)/small-neck ( < 4 mm); and 63% ( 5 of 8) for small-size/wide-neck ( >= 4 mm). A total of 82% ( 9 of 11) recanalization occurred in large aneurysms ( >= 10 to 25 mm). Ten aneurysms (21.3%; 10 of 47) underwent retreatment. Clinical follow-up was obtained in 61 (86%) patients ( average 15 months; range 1 to 37): 87% of patients were Glasgow Outcome Scale 4 or 5. Conclusion - The use of Matrix coils resulted in worse recanalization rates than that reported for Guglielmi detachable bare platinum coils.