Deliberate parent artery occlusion for non-saccular posterior cerebral artery aneurysms

Abstract

Posterior cerebral aneurysms are rare vascular lesions and usually present as non-saccular or dissecting in nature. We present a retrospective review of our experience in the deliberate parent artery occlusion of posterior cerebral artery (PCA) aneurysms.From June 2006 to June 2010, 12 patients (seven men, five women) with posterior cerebral artery non-saccular aneurysms presented to our department and were treated by parent artery occlusion. There were eight (66.7%) aneurysms located at the P2 segment, two (16.7%) at the P2-3 junction, one (8.3%) at the P1-2 junction and one (8.3%) at the P3 segment. Ten of the 12 patients were treated by aneurysm together with parent artery occlusion and two were treated by proximal occlusion.The procedure was technically successful in all cases. Angiography was performed immediately after the procedure in all patients and showed occlusion of the parent vessel with no filling of the aneurysm. Only one patient (8.3%) developed procedure-related transient hemianopsia and recovered within one month. The other 11 patients showed no additional neurological symptoms after procedure. Deliberate parent artery occlusion by detachable coils appears to be well tolerated for P2 or distal segment of PCA in our limited case series. We propose that this technique could be a good treatment option in treating non-saccular aneurysms in this location.

Figure 1

Case 7. A) Right internal carotid artery injection angiogram showed the dissecting aneurysm located at the P2-3 junction of the fetal PCA. B) Angiogram after embolization of the aneurysm and the right PCA. C) Venous phase showed the retrograde flow of the leptomeningeal anastomosis (arrow).

Figure 2

Case 9. A) A T2-weighted MRI showed a flow void at the basil cistern with compression of the left peduncle. B) Left vertebral injection showed the dissecting aneurysm and aplastic P1 segment. C) Left carotid artery injection showed the aneurysm was opacified better from anterior circulation. D) Trans-vertebral embolization under the roadmap from LICA injection. E) Postprocedural angiogram showed the aneurysm were completely occluded

Figure 3

Case 12. Av CT scan showed relative high-intensity at the right basal cistern. B) A 3D angiogram showed the large aneurysm at the right PCA. C) Endosaccular palliative embolization of the aneurysm with the patency of the parent PCA. D) 4 months later, another angiogram showed the enlarged aneurysm and compaction of the coil mass. E) Angiogram showed the proximal embolization of the parent artery and no residual flow to the aneurysm.