CLINICAL STUDIES EVOLUTION OF OCULOMOTOR NERVE PARESIS AFTER ENDOVASCULAR COILING OF POSTERIOR COMMUNICATING ARTERY ANEURYSMS:ANEURO- OPHTHALMOLOGICAL PERSPECTIVE Hadas Stiebel-Kalish, M.D. Department of Ophthalmology, Rabin Medical Center, Petah Tikva, Israel Shimon Maimon, M.D. Division of Interventional Neuroradiology, Department of Radiology, Rabin Medical Center, Petah Tikva, Israel Jacob Amsalem, M.D. Division of Interventional Neuroradiology, Department of Radiology, Rabin Medical Center, Petah Tikva, Israel Rita Erlich, M.D. Department of Ophthalmology, Rabin Medical Center, Petah Tikva, Israel Yuval Kalish, Ph.D. Department of Psychology, University of Melbourne, Melbourne, Australia Z. Harry Rappaport, M.D. Department of Neurosurgery, Rabin Medical Center, Petah Tikva, Israel Reprint requests: Hadas Stiebel-Kalish, M.D., Division of Neuro-ophthalmology, Department of Ophthalmology, Rabin Medical Center, Petah Tikva 49100, Israel. Email: kalishh@clalit.org.il Received, February 28, 2003. Accepted, August 14, 2003. OBJECTIVE: Guglielmi detachable coil treatment is becoming an accepted alternative to microsurgical clipping for select intracerebral aneurysms. Resolution of oculomotor nerve paresis (ONP) after endovascular packing was claimed to be complete in two prior series, with three and six cases. We describe the evolution of ONP after Guglielmi detachable coil treatment of posterior communicating artery aneurysms, and we search for endovas- cular and patient factors correlated with the degree of functional nerve recovery. METHODS: Twelve cases of ONP attributable to posterior communicating artery aneu- rysms were treated with Guglielmi detachable coils between 1999 and 2002. Eleven patients were available for follow-up monitoring. The degree of ONP was recorded at admission, at discharge, after 3 months, and at yearly intervals thereafter. The size of the aneurysm, the duration of ONP before coiling, the degree of coiling, age, and the presence of other microvascular risk factors were correlated with the degree of nerve recovery. RESULTS: Complete resolution of ONP did not occur in any of the 11 cases in this series. However, residual oculomotor nerve deficits did not cause diplopia with primary gaze for 10 of 11 patients. Clinically significant ptosis did not persist for any of the patients. The pupil remained minimally affected in all cases. CONCLUSION: Although mass effect remains after endovascular packing, oculomotor nerve dysfunction improves comparably to the recovery observed after surgical clipping. Contrary to previous reports, typical residual oculomotor nerve deficits persist. Older age and the presence of microvascular risk factors seem to be detrimental to ONP recovery. KEY WORDS: Aneurysm, Oculomotor nerve, Posterior communicating artery Neurosurgery 53:1268-1274, 2003 DOI: 10.1227/01.NEU.0000093495.70639.AE www.neurosurgery-online.com E ndovascular Guglielmi detachable coil (GDC) therapy has an increasingly impor- tant role as an alternative to microsurgical clipping for treatment of select intracerebral an- eurysms (8). Although it is more comfortable for the patient and is often associated with lower complication rates, coiling is not thought to re- solve all of the mass effect caused by aneurysms. The proposed mechanism by which coiling re- lieves adjacent-structure pressure is the lessen- ing of pulsations after aneurysm thrombosis. Resolution of oculomotor nerve paresis (ONP) after endovascular packing was claimed to be complete in two prior series, describing a com- bined total of nine cases (1, 7). We describe a series of 11 patients who were treated with en- dovascular packing for posterior communicat- ing artery (PComA) aneurysms, with close neuro-ophthalmological follow-up monitoring. PATIENTS AND METHODS Two hundred thirty small or large aneu- rysms among 185 patients were treated with endovascular coiling at our institution be- tween 1999 and 2001. A total of 12 patients experienced ONP resulting from PComA an- eurysms treated with GDCs. One patient died shortly after the procedure, as a result of com- plications of cardiovascular disease. The re- maining 11 patients were prospectively exam- 1268 | VOLUME 53 | NUMBER 6 | DECEMBER 2003 www.neurosurgery-online.com