[Preliminary application of keyhole approach for the treatment of posterior circulation aneurysms]

To evaluate the feasibility and efficacy of minimally invasive keyhole approach for the treatment of posterior circulation aneurysms.

Twelve posterior circulation aneurysms were treated via the keyhole approach. Aneurysms were located in basilar artery (BA) in 6 patients (1 in BA bifurcation, 3 in BA-SCA [superior cerebellar artery], 1 in BA-PCA [posterior cerebral artery], 1 in PCA-BA-SCA), in PCA in 5 patients (1 in PCA1-2 segment, 2 PCA2 segment and 2 PCA2-3 segment) and in PICA [posterior inferior cerebellar artery] in 1 patient. The supraorbital keyhole approach was performed in 6 BA and 2 PCA1-2 segment aneurysms, the subtemporal approach in 3 PCA2-3 segment aneurysms and the lateral suboccipital keyhole approach in one PICA aneurysm.

Among those 12 posterior circulation aneurysms, 9 aneurysms were completely clipped, 2 thrombotic PCA2-3 segment giant aneurysms trapped with thrombectomy, one gourd-shaped aneurysm in PICA incompletely clipped with no recurrent hemorrhage in during a 6-month follow-up. No intraoperative rupture of aneurysms occurred in any operation. All patients were discharged without neurological deficits.

Anterior or posterior clinoid process may be drilled off under the keyhole approach to increase the manipulating space while clipping the posterior circulation aneurysms. Controlling the proximal parent artery by balloon catheter increases the operative safety. Neuronavigation is helpful in rapidly locating the distal PCA aneurysm. The individualized keyhole approaches can be applied feasible and effectively for the treatment of posterior circulation aneurysms.