Introduction: Posterior communicating artery aneurysm (PCoA) induced oculomotor nerve palsy (ONP) in acute subarachnoid hemorrhage is a well-established entity. Previous studies have attempted to address the effectiveness of clip ligation or coil embolization on the rate and completeness of ONP resolution, but have been limited by small sample sizes.

Methods: In this multi-centered study 55 patients with ruptured PCoA and acute ONP from January 1991 to October 2013 were reviewed. Included patients had angiographically confirmed PCoA following subarachnoid hemorrhage and complete or partial ONP on admission. Rate of resolution of ONP was determined from treatment date to last known follow-up and was defined as complete vs. partial or no resolution. Resolution data on 83 similarly treated patients was extracted from the literature and combined to increase sample size. Outcomes and treatment groups were directly compared.

Results: A total of 138 patients (67 clipped and 71 coiled) presented with either complete (47%) or partial (53%) ONP. Patients undergoing clipping were more likely to have complete resolution of ONP compared to patients undergoing coiling (71.6% vs. 54.9%, respectively, OR=2.07, 95% CI (1.02 –4.21), p=0.042). Further comparison among the 55 patients in the primary data set showed there was no difference between time to complete resolution (153 vs. 230 days, p=0.214) (Figure 1), aneurysm size (7.3 ±2.5 vs. 6.8 ±2.2 mm, p=0.52), and median time from ONP onset to treatment (2 vs. 2 days, p=0.9) between the clipped and coiled groups, respectively.

Conclusions: In our series of patients with ONP secondary to ruptured PCoA, patients undergoing clipping were more likely to experience complete resolution vs. coiling. There was no difference between the treatment groups with regard to aneurysm size, time from ONP onset to treatment, and rate of complete resolution. Larger multi-centered studies are needed to assess these treatments for ONP resolution with greater precision.

Patient Care: 1) By understanding that all other variables being equal, patients who present with subarachnoid hemorrhage from a ruptured posterior communciating artery aneurysm and third nerve palsy should have more consideration given to clip ligation to insure that their cranial neuropathy will completely resolve over time

Learning Objectives: 1) Understand the difference that coil embolization or clip ligation has on the resolution of third nerve palsy with acute posterior communicating artery aneurysms 2) Know that this is a rare occurrence that requires patients from multiple years and hospitals to accurately assess either treatment

References: 1. Silva MD, Brazis P, Miller D, Wharen R, Smith CC, Freeman WD. True- true- unrelated? A delayed onset, complete third-nerve palsy after traumatic subarachnoid hemorrhage. Journal of vascular and interventional neurology. Jun 2013;6(1):22-25. 2. Chalouhi N, Theofanis T, Jabbour P, et al. Endovascular treatment of posterior communicating artery aneurysms with oculomotor nerve palsy: clinical outcomes and predictors of nerve recovery. AJNR. American journal of neuroradiology. Apr 2013;34(4):828-832. 3. Motoyama Y, Nonaka J, Hironaka Y, Park YS, Nakase H. Pupil-sparing oculomotor nerve palsy caused by upward compression of a large posterior communicating artery aneurysm. Case report. Neurologia medico-chirurgica. 2012;52(4):202-205. 4. Guresir E, Schuss P, Seifert V, Vatter H. Oculomotor nerve palsy by posterior communicating artery aneurysms: influence of surgical strategy on recovery. Journal of neurosurgery. Nov 2012;117(5):904-910. 5. Balossier A, Postelnicu A, Khouri S, Emery E, Derlon JM. Third nerve palsy induced by a ruptured anterior communicating artery aneurysm. British journal of neurosurgery. Oct 2012;26(5):770-772. 6. Ko JH, Kim YJ. Oculomotor nerve palsy caused by posterior communicating artery aneurysm: evaluation of symptoms after endovascular treatment. Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences. Dec 2011;17(4):415-419. 7. Guresir E, Schuss P, Setzer M, Platz J, Seifert V, Vatter H. Posterior communicating artery aneurysm-related oculomotor nerve palsy: influence of surgical and endovascular treatment on recovery: single-center series and systematic review. Neurosurgery. Jun 2011;68(6):1527-1533; discussion 1533-1524. 8. Yerramneni VK, Chandra PS, Kasliwal MK, et al. Recovery of oculomotor nerve palsy following surgical clipping of posterior communicating artery aneurysms. Neurology India. Jan-Feb 2010;58(1):103-105. 9. Santillan A, Zink WE, Knopman J, Riina HA, Gobin YP. Early endovascular management of oculomotor nerve palsy associated with posterior communicating artery aneurysms. Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences. Mar 2010;16(1):17-21. 10. Kassis SZ, Jouanneau E, Tahon FB, Salkine F, Perrin G, Turjman F. Recovery of third nerve palsy after endovascular treatment of posterior communicating artery aneurysms. World neurosurgery. Jan 2010;73(1):11-16; discussion e12. 11. Mansour N, Kamel MH, Kelleher M, et al. Resolution of cranial nerve paresis after endovascular management of cerebral aneurysms. Surgical neurology. Nov 2007;68(5):500-504; discussion 504. 12. Mansour N, Choudhari KA. Outcome of oculomotor nerve palsy from posterior communicating artery aneurysms: comparison of clipping and coiling. Neurosurgery. Mar 2007;60(3):E582; author reply E582. 13. Chen PR, Amin-Hanjani S, Albuquerque FC, McDougall C, Zabramski JM, Spetzler RF. Outcome of oculomotor nerve palsy from posterior communicating artery aneurysms: comparison of clipping and coiling. Neurosurgery. Jun 2006;58(6):1040-1046; discussion 1040-1046. 14. Stiebel-Kalish H, Maimon S, Amsalem J, Erlich R, Kalish Y, Rappaport HZ. Evolution of oculomotor nerve paresis after endovascular coiling of posterior communicating artery aneurysms: a neuro-ophthalmological perspective. Neurosurgery. Dec 2003;53(6):1268-1273; discussion 1273-1264. 15. Inamasu J, Nakamura Y, Saito R, Kuroshima Y, Ohba S, Ichikizaki K. Early resolution of third nerve palsy following endovascular treatment of a posterior communicating artery aneurysm. Journal of neuro-ophthalmology : the official journal of the North American Neuro-Ophthalmology Society. Mar 2002;22(1):12-14. 16. Birchall D, Khangure MS, McAuliffe W. Resolution of third nerve paresis after endovascular management of aneurysms of the posterior communicating artery. AJNR. American journal of neuroradiology. Mar 1999;20(3):411-413. 17. Matsumoto K, Kuriyama M, Tamiya T, Ohmoto T. Direct clip obliteration of a ruptured giant aneurysm of the posterior communicating artery: case report. Neurosurgery. Oct 1997;41(4):939-942; discussion 942-933. 18. Kyriakides T, Aziz TZ, Torrens MJ. Postoperative recovery of third nerve palsy due to posterior communicating aneurysms. British journal of neurosurgery. 1989;3(1):109-111. 19. Perneczky A, Czech T. Prognosis of oculomotor palsy following subarachnoid hemorrhage due to aneurysms of the posterior communicating artery. Zentralblatt fur Neurochirurgie. 1984;45(3):189-195.