No abstract

Aneurysms of the posterior inferior cerebellar artery (PICA) are rarely encountered. In particular, due to frequent anatomic complexity and the presence of nearby critical structures, PICA origin aneurysms are difficult to treat. However, recent reports of anecdotal cases using advanced endovascular instruments and skills have made the results of endovascular treatment rather outstanding. PICA preservation is the key to a successful endovascular treatment, based on the premise that a PICA origin aneurysm is well occluded. To secure PICA flow, stenting into the PICA would be the best method, however, it is nearly impossible technically via the ipsilateral vertebral artery (VA) if the PICA arose at an acute angle from the sac. In such a case, a bilateral approach for stent-assisted coiling can be a creative method for achievement of two goals of both aneurysm occlusion and PICA preservation: ipsilateral approach for coil delivery and contralateral cross-over approach for stent delivery via a retrograde smooth path into the PICA.

PurposeThe optimal management of geometrically complex aneurysms remains challenging. The aim of this retrospective study was to evaluate the safety and feasibility of branch-selective technique (BT) in wide-necked aneurysms with an acute angle branch incorporated into the sac.Materials and MethodsEight consecutive patients harboring wide-necked cerebral aneurysms with an incorporated, acute angle branch (mean, 30.4°) underwent coiling over an 18-month period. Dome-to-neck ratio ranged from 0.9 to 1.8 (mean, 1.2). Every procedure utilized BT, i.e., stent- or catheter-assisted coiling through the incorporated branch.ResultsTechnical success was achieved in all cases. With the aim to avoid the risk of aneurysmal rupture during struggling intraaneurysmal wire navigation, a 'looping method' and retrograde approach of a preshaped 0.014' microcatheter (C or J) was used for branch access in five cases and a 'looping method' and antegrade approach in one case. In the remaining one, just the C-preshape was enough to directly enter the branch without intraaneurysmal wire navigation. Overall, stent-assisted coiling was performed in seven cases, while catheter-assisted coiling was undertaken in one. The only complication was thrombotic posterior inferior cerebellar artery occlusion in one case, which was recanalized after tirofiban infusion. New neurological deficits were not identified in any cases.ConclusionBT seems safe and feasible for wide-necked aneurysms with an acute angle branch incorporated into the sac. The looping method may offer safe access to the incorporated, acute angle branch and should be considered for replacement of the fearful intra-aneurysmal wire navigation.