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Minimally Invasive Thumb-sized Pterional Craniotomy for Surgical Clip Ligation of Unruptured Anterior Circulation Aneurysms
Published on: August 11, 2015
Isolated third nerve palsy associated with a ruptured anterior communicating artery aneurysm
J Bradley White1, Kennith F Layton, Harry J Cloft
1The Department of Neurological Surgery, The Mayo Clinic, 200 1st Street SW, Rochester, MN 55902, USA. white.brad@mayo.edu
Introduction:
An oculomotor palsy in the setting of aneurysmal subarachnoid hemorrhage is often due to compression by a posterior communicating artery aneurysm. Anterior communicating artery (ACOM) aneurysms may produce ophthalmologic symptoms of the anterior visual pathways, but rarely ever lead to a 3rd nerve palsy. This report describes a rare case of an isolated oculomotor palsy in a patient who experienced subarachnoid hemorrhage from an ACOM aneurysm.
Clinical Presentation:
A 46-year-old male presented to the emergency department with headache, emesis, and an isolated left third nerve palsy-the remainder of his exam was normal. A head CT showed diffuse subarachnoid hemorrhage that was later attributed to an ACOM aneurysm as determined by angiography.
Intervention:
Due to the configuration of the aneurysm, it was not deemed treatable by endovascular means. Following a successful clipping, the patient experienced a delayed, transient, monocular visual loss. Upon follow-up, his oculomotor palsy had completely resolved.
Conclusion:
In very rare circumstances, an ACOM aneurysm may produce an isolated third nerve palsy. The etiology of the palsy is likely related to clot formation and/or irritating blood products.
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