Endoscopic treatment of distal choroidal artery aneurysm.

Distal choroidal artery aneurysms stemming from the lateral wall of the ventricles are rare and are mostly associated with moyamoya disease. The treatment of these aneurysms is difficult because of their deep location. The authors report the case of a 50-year-old woman followed for moyamoya disease presenting with 2 intraventricular hemorrhages. Cerebral angiography showed an aneurysm located on the left distal choroidal artery. Magnetic resonance imaging also demonstrated that the lesion protruded from the lateral wall of the trigone of the left lateral ventricle. Using MR imaging-guided stereotactic localization, the aneurysm was accurately reached endoscopically and successfully resected from the parent artery. The patient was discharged neurologically intact. To the best of the authors' knowledge, this is the first report of a successfully endoscopically treated distal anterior choroidal artery aneurysm. Endoscopic surgery may be added to the armamentarium of procedures used to treat intraventricular aneurysms.