Aneurysm of superior branch of anterior choroidal artery mimicking carotid bifurcation aneurysm--case report

Usefulness of Motor-Evoked Potentials Monitoring for Neurosurgical Treatment of an Unusual Distal Anterior Choroidal Artery Aneurysm

A 35 years old woman presented with an acute meningeal syndrome following an intra ventricular haemorrhage without subarachnoid haemorrhage. The angiography demonstrated a 6 mm partially thrombosed saccular aneurysm at the plexal point of the right anterior choroidal artery (AChoA). It was surgically approached inside the ventricle through a trans-temporal corticotomy. The aneurysm was excised after distal exclusion of the feeding artery under motor-evoked potentials monitoring. Of the 19 cases of distal AChoA aneurysm neurosurgical treatment, this is the only one performed under electrophysiology monitoring, a simple and safe method to detect and prevent motor tract ischemia. We discuss this rare case, along with a comprehensible review of the literature of the previous surgical cases of distal AChoA aneurysms.

Ruptured True Anterior Choroidal Artery Aneurysm in Cisternal Segment

BACKGROUND

Rupture of a true anterior choroidal artery (AChA) aneurysm in the cisternal segment is extremely rare, whereas cases of a distal AChA aneurysm associated with moyamoya disease are increasingly reported.

CASE DESCRIPTION

A 58-year-old woman presented with a severe headache and vomiting. Computed tomography demonstrated a subarachnoid hemorrhage without intraventricular or intracerebral hemorrhaging. Cerebral angiogram findings revealed a proximal AChA aneurysm mimicking an internal carotid artery aneurysm at the origin of the AChA. Intraoperative findings demonstrated a ruptured aneurysm located on a bend of the proximal AChA in the carotid cistern. Neck clipping of the aneurysm with preservation of the AChA led to a good outcome.

CONCLUSIONS

A rare case of ruptured true AChA aneurysm in the cisternal segment, unrelated to moyamoya disease, is presented as a cause of subarachnoid hemorrhage.

Distal anterior choroidal artery aneurysms

BACKGROUND

Distal AChoA aneurysms are quite rare. Only 12 operated cases have been reported in the English medical literature. Treatment of these aneurysms is also difficult because of their deep location, small size, and angioarchitecture.

METHODS

The authors report 2 additional patients with aneurysms, arising from the distal AChoA and located within the temporal horn of the lateral ventricle. In the first patient, the aneurysm could also be visualized with CTA, which is the first demonstration in the literature.

RESULTS

The aneurysms were explored and resected via a transtemporal/ventricular approach in both patients. One patient was discharged as neurologically intact and the other died because of severe vasospasm.

CONCLUSIONS

The conclusions drawn from our experience and a comprehensive review of the literature include the following: (1) A distal AChoA aneurysm should be considered in patients with isolated medial temporal intracerebral hematoma with intraventricular extension. (2) These aneurysms are frequently very small (<5 mm). Therefore, they cannot be detected on initial angiograms in some cases. (3) These small aneurysms cannot be usually clipped without sacrificing the parent artery. (4) Sacrificing distal AChoA (beyond the plexal point) does not usually cause any neurological deficit, but, whenever possible, this artery should be preserved.

Ruptured distal anterior choroidal artery aneurysm presenting with right intracerebral haematoma: clipping aided by subpial uncal resection

This report describes a rare case of a distal right anterior choroidal artery aneurysm which developed a right intracerebral haematoma and intraventricular haemorrhage and was treated by surgical exploration and clipping with the aid of a limited subpial resection of the uncus and ambient gyrus. The technique of limited subpial uncal resection allows the surgeon to follow the anterior choroidal artery without much difficulty, achieves proximal control early and aids in the eventual clipping procedure.