Zygomatic Anterolateral Temporal Approach for P1/P2 segment complex posterior cerebral aneurysm: a single-center retrospective study.

Treating complex posterior cerebral artery (PCA) aneurysms, such as fusiform, giant, and dissecting aneurysms, poses significant challenges. Parent artery occlusion carries a risk of ischemic stroke and fails to alleviate mass effects. This study aims to analyze the technical nuances and patient outcomes of treating complex PCA aneurysms, ranging from the P1 to P2P segments, using a Zygomatic Anterolateral Temporal Approach(ZATA) combined with flow reconstruction. This study was a retrospective study. Surgical treatment was performed on twelve patients with complex PCA aneurysms located in the P1 to P2P segments. Ten patients underwent flow reconstruction including Superficial Temporal Artery(STA)-Middle Cerebral Artery(MCA),Internal Maxillary Artery(IMA)-Radial Artery(RA)-MCA,STA-PCA(P2), and IMA-RA-PCA(P2). The aneurysm occlusion rate, surgical complications, and patient prognosis, including stroke occurrence/ modified Rankin Scale(mRS), were recorded and analyzed. Using the ZATA, all twelve complex PCA aneurysms were successfully clipped/resected/trapped. This included two high-position aneurysms (> 3 mm above the posterior clinoid process) at the P1/P2 junction and three P2P aneurysms. The mass effects of six large or giant aneurysms were resolved or alleviated. Postoperative and follow-up CTA/DSA confirmed the patency of the bypass vessels. Four patients experienced strokes in the perioperative period, with three ischemic and one hemorrhagic. The median follow-up period was 28.5 months. At the last follow-up, the good prognosis rate (mRS ≤ 2) was 83.3%, and one patient had died. Clipping/resection/trapping of aneurysms via the ZATA, combined with flow reconstruction, is a feasible option for treating complex PCA aneurysms from the P1 to P2P segments. This approach helps maintain or improve cerebral perfusion in the affected vascular territory.

Trans-lateral ventricular approach for surgical treatment of high-located P2-P3 junction posterior cerebral artery aneurysms: from anatomical research to clinical application.

BACKGROUND: Posterior cerebral artery (PCA) aneurysms, though rare, pose treatment challenges. Endovascular therapy is the preferred option, but microsurgery becomes necessary in certain cases. Various microsurgical approaches have been suggested for PCA aneurysms, particularly those at the P2-P3 junction. This study highlights the trans-lateral ventricular approach (TVA) for addressing these complex aneurysms. This study aims to assess the feasibility and safety of the trans-lateral ventricular approach (TVA) for treating high-located complex PCA aneurysms at the P2-P3 junction. The study evaluates both clinical outcomes and anatomical considerations. METHODS: Two cases of PCA aneurysms at the P2-P3 junction were treated using TVA in 2019. Navigation-guided entry via the interparietal sulcus was planned. Ventriculostomy was performed from the cortex to the lateral ventricle's atrium. Medial atrial floor dissection exposed PCA's P2-P3 segments. Neuronavigation and ultrasound-aided guidance was used. Anatomical studies on fixed and contrast-perfused specimens refined the approach. RESULTS: Both cases saw successful aneurysm clipping. The unruptured aneurysm patient was discharged in 6 days. The poor-grade SAH patient required extended ICU care, moving to rehabilitation with mRS = 4. The unruptured complex aneurysm case exhibited no deficits, returning to work in 3 months. Anatomical dissections validated TVA for high-located P2-P3 junction PCA aneurysms. CONCLUSION: While endovascular therapy remains primary, this study demonstrates the viability of navigation-guided TVA for select high-located P2-P3 junction PCA aneurysms. Successes and challenges underscore the importance of patient selection and anatomical awareness.

Posterior Cerebral Artery Aneurysms: Parent Vessel Occlusion Being a Viable Option in the Era of Flowdivertors.

BACKGROUND AND PURPOSE: The purpose of this study is to evaluate posterior cerebral artery (PCA) aneurysms along with the efficacy, safety, procedural, and clinical outcome of the endovascular management of these aneurysms. We studied different techniques of endovascular treatment such as selective aneurysmal coiling, parent artery occlusion, and stent-assisted coiling in PCA aneurysms. METHODS: From 2010 to 2017, 11 patients (8 females, 3 males) harboring a PCA aneurysm were treated via an endovascular approach. Seven of eleven aneurysms were saccular in nature; four were fusiform shaped. All aneurysms were treated using detachable coils either by selective obliteration of the aneurysm sac or by parent artery occlusion. In one patient, stent-assisted coiling of PCA aneurysm was done, and in one patient, flowdivertor along with few coils used to treat the aneurysm. RESULTS: Five of the eleven aneurysms were successfully treated with preservation of the parent artery, and the other six were treated with aneurysm coiling along with parent vessel occlusion. Of the six where parent vessel occlusion was done, one developed transient hemiparesis which recovered on follow-up and none developed significant disabling vision abnormality. No mortality was noted. CONCLUSION: Aneurysms of the PCA are rare compared with other locations in the intracranial circulation. These aneurysms can effectively be treated by permanent occlusion of the parent artery even in this era of flowdivertors - however, in these cases, thorough knowledge of PCA segmental anatomy is crucial in order to select the site of occlusion and to avoid major neurological deficits.

A New Window for the Treatment of Posterior Cerebral Artery, Superior Cerebellar Artery, and Basilar Apex Aneurysm: The Expanded Endoscopic Endonasal Approach.

OBJECTIVE: To explore the feasibility of an endoscopic endonasal transclival approach to treat aneurysms arising in the basilar apex, posterior cerebral arteries, and superior cerebellar arteries. STUDY DESIGN: Cadaveric anatomical study. PARTICIPANTS: Fifteen cadaveric specimens. MAIN OUTCOME MEASURES: Degree of surgical exposure of each artery attained, distance from the nasal vestibule to these three arteries, and feasibility of clipping these vessels using standard vascular clip applicators. RESULTS: Both posterior cerebral arteries were exposed, 0.67 cm (standard deviation [SD]: 0.2) on the right side and 0.59 cm (SD: 0.2) on the left side. Both right and left superior cerebral arteries were exposed, 0.6 cm (SD: 0.2) and 0.7 cm (SD: 0.3), respectively. The length of the basilar artery exposed was 2.6 cm (SD: 0.3). The distance from the nasal vestibule to the posterior cerebral artery, superior cerebellar artery, and basilar apex was 10 cm with an SD of ± 0.7, 0.6, and 0.8 cm, respectively. We were able to apply clips on each of these three vessels with a minimal alteration of surrounding normal tissue. CONCLUSION: The endoscopic endonasal transclival approach represents a potentially feasible surgical corridor to treat aneurysms arising from these vessels.

Endovascular Treatment of the Posterior Cerebral Artery Aneurysms: Single-Center Experience and a Systematic Review.

BACKGROUND: Endovascular treatment of posterior cerebral artery aneurysms is challenging because of the particular features of posterior circulation vessels. We performed a systematic review of the literature, to assess safety and efficacy associated to their endovascular treatment. METHODS: Through a literature search, we identified 20 studies that met our inclusion criteria. We also performed a retrospective analysis of patients treated at our institution during the last 10 years. Demographics, angiographic features, clinical presentation, and outcome were extracted from each study. Data were combined using a random effects model and heterogeneity was assessed by I(2). RESULTS: We retrieved 7 patients from our institutional series and 246 from the literature. Overall, 253/259 patients/aneurysms were included in this study. A selective coiling was performed in 27% of cases, a stent-assisted coiling in 2%, and a parent artery occlusion in 62%. Immediate complete/near-complete occlusion was obtained in 96% of cases and maintained in 90% at follow-up. No differences were observed between ruptured and unruptured aneurysms. Ischemic complications were reported in 15% of cases, although the most frequent was a hemianopsia in 7%; a hemiparesis was reported in only 2% of cases. Mortality was overall 1%. Ischemic complications were more frequent among patients who underwent nonselective treatment (P < 0.01). CONCLUSIONS: Endovascular treatment of posterior cerebral artery aneurysms is associated with increased degree of occlusion and low recurrence rate. However, a parent artery occlusion implies complications, even although most of them are minor events such as hemianopsia.