Aneurysms of the P2P Segment of Posterior Cerebral Artery: Case Report and Surgical Steps

Abstract

The posterior cerebral artery (PCA) is divided into 4 segments: precommunicating segment (P1), postcommunicating segment (P2), quadrigeminal segment (P3), and calcarine segment (P4). Small aneurysms are more prevalent than large aneurysms in patients with ruptured aneurysms. P2 and P3 aneurysms are usually managed by the subtemporal approach. This is a case report of rupture saccular aneurysm of posterior cerebral artery on P2P segment. The authors show the surgical steps of these rare aneurysms with an illustrative case.

Endovascular Therapeutic Occlusion of the Posterior Cerebral Artery: An Option for Ruptured Giant Aneurysm in a Child

“…The most common clinical presentation was headache in 75% [6] and subarachnoid hemorrhage in 55-65% of the cases [4,5,6], followed by mass effect, epileptic seizures and cerebral vascular accidents [2,3,9]. Some authors had already noticed that rebleeding is more frequent in the pediatric population if compared to adults, occurring in up to 52% [2], possibly due to the delay in making the right diagnosis.…”

“…Anatomically, PCA is divided into four segments: P1 = precommunicating segment, P2 = postcommunicating segment, P3 = quadrigeminal segment, and P4 = calcarine segment, with subdivision of the second segment into anterior P2A (crural) and posterior P2P (ambient) [9]. …”

“…Surgical clipping is the preferred treatment for most pediatric aneurysms due to the low risk of recurrence over the long term [10,11]. Pterional craniotomy is the usual approach to P1 and P1-P2 junction aneurysms, while subtemporal craniotomy is the preferred approach to those in the P2 and P3 segments [9]. Whereas giant aneurysms may present proliferative disease in the vessel wall, trapping with proximal and distal parent vessel clipping followed by surgical excision is considered the best therapy [12], and could have been an option in this case.…”

The oculomotor-tentorial triangle. Part 1: microsurgical anatomy and techniques to enhance exposure

“…This finding is in concordance with previous studies emphasizing that the P 2P -PCA could not be exposed during the pretemporal approach. 1,11,37,38…”

“…17,25,38 In a transsylvian approach, as the surgical target moves posterolaterally around the cerebral peduncle, the temporal lobe and the tentorium become major obstacles to more lateral and posterior exposure. 1,23,37,38 Likewise, moving anteriorly from the ambient cistern toward the crural and interpeduncular cisterns during a subtemporal exposure, the surgical maneuverability becomes progressively limited as the target assumes a deeper position on the ventral aspect of the midbrain. 38 Triangular corridors are defined to facilitate orientation during these surgical approaches.…”