Aneurysms Arising From the Fenestrated Middle Cerebral Artery

Endovascular treatment of unruptured aneurysm arising from duplicate origin of the middle cerebral artery - A case report and literature review

Background

Duplicate origin of the middle cerebral artery (MCA) is a rare variation of MCA, often mislabeled as the fenestration of the M1 segment of MCA.

Case Description

The authors treated an unruptured aneurysm, 8 mm in diameter, associated with a duplicate origin of MCA in a 42-year-old woman who underwent magnetic resonance imaging for transient vertigo. Clipping surgery was inapplicable due to the lack of space to insert clip blades between the neck and two origins of MCA. Under stent-assisted maneuver, the aneurysm sac was successfully obliterated using three coils, resulting in Raymond-Roy class 1 occlusion status. Digital subtraction angiography performed 3 months after the embolization showed complete obliteration of the aneurysm. So far, only 11 patients with aneurysms associated with duplicate origin of MCA have been reported. We performed a literature review of this very rare combination. The size of aneurysms ranged from 2 to 8 mm, with a mean of 5.2 mm. The neck of the aneurysm is mainly located at the corner between the inferior limb and the internal carotid artery. Ours is the youngest and has the largest aneurysm.

Conclusion

Aneurysm can arise from duplicate origin of MCA, for which stent-assisted coiling may be an appropriate treatment modality.

Retrospective analysis of image characteristics of 76 cases of cerebral vascular fenestrations

Objectives

This study aims to summarize the clinical and imaging features of cerebral vascular fenestration and to explore the association between cerebral vascular fenestration and cerebral infarction and aneurysm.

Materials and methods

The computed tomography angiography (CTA), magnetic resonance angiography (MRA), and digital subtraction angiography (DSA) imaging data of 76 cases of cerebral vascular fenestration from January 2021 and December 2021 in the Yantai Yuhuangding Hospital Affiliated to Qingdao University were analyzed. The general information was described. The location, morphology, and size of cerebral vascular fenestration were described. The association between cerebral vascular fenestration and infarction and aneurysm was analyzed.

Results

Among 76 patients, a total of 80 fenestrations were detected (two patients had three fenestrations), and basilar artery fenestration was the most common (28/80). The fenestration <5 mm was 43/80, 5-10 mm was 12/80, and ≥10 mm was 25/80. Moreover, 19 patients had other vascular diseases: 10 with aneurysms, 5 with moyamoya diseases, and 4 with cerebral artery dissections. Except for one aneurysm at the site of the fenestration, other aneurysms were separate from the fenestrations. In addition, 37 patients had cerebral infarctions, of which 16 had cerebral infarctions in the blood supply area of the arterial fenestration. Among these 16 patients, there was more cerebral infarction in posterior circulation than in anterior circulation. However, no statistically significant differences were detected in the risk factors between the fenestration-relevant cerebral infarctions group and the non-fenestration-relevant cerebral infarctions group.

Conclusion

In our study, cerebral vascular fenestration occurred most frequently in the basilar artery and may be combined with other vascular diseases. Fenestration in posterior circulation may be related to cerebrovascular diseases. Nonetheless, no clear clinical relevance was observed between fenestration and cerebral infarction. Also, we did not find a definite association between fenestration and aneurysm. For fenestration patients with cerebral infarctions, long-term antiplatelet and statin therapy may be safe and effective.

The Clinical Characteristics and Treatment Considerations for Intracranial Aneurysms Associated With Middle Cerebral Artery Anomalies: A Systematic Review

Background: As a result of their low incidence, most of the studies on intracranial aneurysms associated with middle cerebral artery (MCA) anomalies were presented as case reports or small case series. No systematic review on this specific entity has been conducted.

Methods: A PubMed search of the published studies was performed on April 6th, 2019 for patients who had intracranial aneurysms associated with MCA anomalies. The languages included in this study were English, Chinese, and Japanese.

Results: Finally, 58 articles reporting of 67 patients including 1 case in our center were included. The identified patients (37 females, 55.2%) aged from 4 to 81 (49.85 ± 15.22) years old. 50 (50/67, 74.6%) patients presented with hemorrhagic stroke either from the MCA anomalies associated aneurysms or other sources. 63 aneurysms (63/67, 94.0%) were saccular, 3 (4.5%) were dissecting or fusiform, and 1 (1.5%) was pseudoaneurysm. 32 (32/65, 49.2%) patients had other concurrent cerebrovascular anomalies. 56 (83.6%) patients underwent open surgeries, 8 (11.9%) patients underwent endovascular treatment, and 3 (4.5%) patients were conservatively managed. 56 (56/61, 91.8%) patients achieved a good recovery.

Conclusions: The pathophysiological genesis of intracranial aneurysms associated with MCA anomalies is still obscure. The inflicted patients tend to have other concurrent cerebrovascular anomalies, which denotes that congenital defect in cerebrovascular development might play a role in this process. Most of the affected patients could experience a good recovery after treatment.