Evolution of oculomotor nerve paresis after endovascular coiling of posterior communicating artery aneurysms: a neuro-ophthalmological perspective.

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 endovascular and patient factors correlated with the degree of functional nerve recovery. Methods Twelve cases of ONP attributable to posterior communicating artery aneurysms 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.