Anatomical Variation in Sylvian Fissure of Brain in Adult Population: Magnetic Resonance Imaging Based Study

Abstract Introduction: A crucial surgical landmark on the cerebrum’s lateral surface is Sylvian fissure (SF). SF is an important surgical route in pterional approach in vascular neurosurgery for operating aneurysms of the circle of Willis. The research aims to determine anatomical variations of SF in adult population. Methodology: This was a retrospective, descriptive study based on the records to identify magnetic resonance imaging (MRI)-based anatomical changes in SF. MRI of 110 subjects was examined employing 1.5-T MRI system. All scans were confirmed by the radiologist. Sample size calculation was done by statistical analysis and also looking at feasibility as the medical college is situated on outskirts of the city, limiting to availability of such patients. Results: Current research demonstrated that Type 4 SF (narrow SF with a frontal or temporal lobe herniation) was prevalent. The difference of SF types was statistically significant in younger patients when compared to older patients. In cases of more than 50 years of age, type 1 (wide and straight SF) had been found most prevalent and within patients younger than 50 years of age, type 2 and 4 (twisted and narrow SF) was displayed prevalently. Types of SF on both sides of the cerebral hemisphere were found similar with no statistically significant difference. Conclusion: Preoperative information on SF anatomical variations is very useful for neurosurgeons to treat vascular aneurysms of the circle of Willis.