Variations in branching pattern of middle cerebral artery using CT angiography in South Indian population

Middle cerebral artery (MCA) variants are rare compared to that of the other two cerebral arteries. Incidence of variations like duplication, fenestration, accessory vessel and early branching ranges from 0.17 to 4%. However, the literature describing MCA variations using CT Angiography (CTA) is limited, so this study was planned to determine the incidence of MCA branching pattern in Indian population using CTA. Datasets of CTA of 578 MCA from 289 patients (180 males and 109 females), with average age of 49.29±16.16 years (range of 11 to 85 years), from a tertiary care hospital were systematically reviewed for variations in branching pattern. Cases involving aneurysms and infarcts were excluded from the study. Four branching patterns of MCA were seen. Pattern I: single trunk in 0.17% (1/578) cases, on left side. Pattern II: early bifurcation in 0.52% (2/578) cases, two cases on right and one on left side. Pattern III: bifurcation, in 97.75%, (565/578) cases, 46.15% (6/13) cases on right and 53.84% (7/13) on left side. Pattern IV: trifurcation, in 1% (6/578), two cases on right and four on left side. Duplicated MCA seen in 0.34% (2/578) cases, both on the right side. The fenestration of MCA seen in 0.17% (1/578), on the left side. No case of accessory MCA was seen. Awareness of these anatomical variations in the branching pattern of MCA is valuable for clinicians and surgeons handling cases of intracranial aneurysms and infarcts. Thus, data from this study would help surgeons minimize errors and provide the best possible outcome to the patients