Cortical middle cerebral artery aneurysms: Scoping review of presentation and aneurysmal characteristics

Background: Cortical middle cerebral artery (cMCA) aneurysms represent a nonnegligible proportion of all intracranial aneurysms. While studies on proximal MCA aneurysms are growing, large data on cMCA aneurysms are still lacking. Methods: PubMed, ScienceDirect, and Embase were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies that described cMCA. Data extraction and quality assessment were performed according to preestablished guidelines. Results: Of the 7306 studies screened, 50 were included, yielding 58 patients harboring cMCA aneurysms. The mean age was 33 years old, and females accounted for 48.3% of patients. Distribution of aneurysms among cMCA branches was as follows: angular (17.2%, n = 10), central and posterior parietal (12.1%, n = 7), prefrontal (8.62%, n = 5), posterior temporal (6.9%, n = 4), precentral (5.1%, n = 3), postcentral (3.45%, n = 2), and temporooccipital and anterior temporal (1.7%, n = 1). No aneurysms were reported from the orbitofrontal, temporopolar, or middle temporal branches. In 18 cases (31%), the aneurysm location could not be precisely identified and was categorized as unspecified. Most of cMCA aneurysms were solitary (87.9%, n = 51), saccular in shape (67.2%, n = 39), idiopathic in nature (50%, n = 29), small in size (50%, n = 16/32), left-sided (52.1%, n = 25/48), and presented in a ruptured state (75.4%, V43/57). Headache was the most common presenting symptom (67.2%). Surgical treatment was the preferred option (72.4%, n = 42/58), and most cases achieved favorable clinical outcomes on long-term follow-up (88.9%, n = 48/54). Conclusion: This review provides valuable insights into cMCA aneurysms by providing detailed branch-specific frequency data with an emphasis on anatomical, clinical, and treatment characteristics.