Microneurosurgical Management of Posterior Communicating Artery Aneurysm- A contemporary series from Helsinki

Abstract Objective Our purposes are to analyze microsurgical techniques and to determine correlations between microsurgical techniques with the radiographic findings in the microneurosurgical treatment of the posterior communicating artery aneurysms (PCoAAs). Methods The authors retrospectively analyzed radiographic findings and videos of surgery in 64 patients with PCoAAs who underwent microsurgical clipping by the senior author from August 2010-2014. Results From 64 aneurysms, 30 (47%) had SAH that necessitated the lamina terminalis fenestration (odds ratio [OR], 67.67; P < 0.001) and the Liliequist’s membrane fenestration (OR, 19.62; P < 0.001). The low-lying aneurysms significantly necessitated the coagulation of the dura covering the anterior clinoid process (ACP) (OR, 7.43; P = 0.003) or anterior clinoidectomy (OR, 91.0; P < 0.001). We preferred straight clips in 45 (83%) of 54 postero-lateral projecting aneurysms (OR, 45.0; P < 0.001) but preferred curved clips for postero-medial projecting aneurysms (OR, 6.39; P = 0.008). The mean operative time from the brain retraction to the final clipping was 17 min 43 sec. Postoperative CTA revealed complete occlusion of 60 (94%) aneurysms. Three (4.6%) patients with SAH suffered postoperative lacunar infarction. Conclusion For ruptured aneurysms, the lamina terminalis and the Liliequist’s membrane fenestration are useful for additional CSF drainage. For low-lying aneurysm, coagulation of the dura covering the ACP or tailored anterior clinoidectomy might be necessary for exposing the proximal aneurysm neck. Type of clips depends on the direction of projection. The microsurgical clipping of the PCoAAs can achieve good immediate complete occlusion rate with low postoperative stroke rate.