RADIOLOGICAL LANDMARKS AND COMMON VARIATIONS OF THE CEREBRAL CORTEX
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Keywords
Neuroimaging, MRI Landmarks, Cerebral Cortex, Anatomical Variation, Neuroradiology, Cortical Morphometry, Sulcal Patterns.
Abstract
Background: The precision of modern neurosurgery and neurology is increasingly dependent on the radiological identification of the cerebral cortex's functional topography. While standard anatomical atlases provide a foundational "map," inter-individual variations in sulcal and gyral patterns—often referred to as "brain fingerprints"—present significant challenges for accurate radiological interpretation. Misidentification of these landmarks can lead to suboptimal surgical planning or errors in localizing pathological lesions.
Objective: This review aims to systematically categorize the primary radiological landmarks of the cerebral cortex and document the most prevalent anatomical variations encountered in clinical practice. The study evaluates the reliability of these landmarks across different imaging modalities, specifically 3-Tesla (3T) and 7-Tesla (7T) Magnetic Resonance Imaging (MRI).
Methods: A comprehensive analysis was performed on a cohort of high-resolution neuroimaging datasets and existing morphometric literature. Specific attention was given to "invariant" landmarks (e.g., the Sylvian fissure) versus "highly variant" zones (the prefrontal and temporoparietal junctions). Radiological signs, such as the "Omega sign," "M-shape" of the pars orbitalis, and the "bracket sign" of the marginal sulcus, were evaluated for their diagnostic consistency.
Results: The findings indicate that while primary landmarks like the Central Sulcus are identifiable in 98% of cases, their specific morphology (e.g., bifid or interrupted patterns) varies in approximately 15% of the population. Variations in the Superior Temporal Sulcus and the Intraparietal Sulcus were found to be the most frequent, often displacing eloquent language and visuospatial zones. The review further highlights the "Petalia" effect and hemispheric asymmetries as critical factors in avoiding "side-of-pathology" errors during rapid radiological assessment.
Conclusion: Understanding the spectrum of cortical variations is essential for moving beyond "template-based" radiology toward "patient-specific" diagnostics. This review provides a standardized framework for radiologists and neurosurgeons to navigate cortical heterogeneity, ensuring that anatomical variations are recognized not as anomalies, but as critical components of the individual’s functional architecture.
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Dr. Abhimanu Kumar
Post-Doctoral Degree (Doctor of Science) D.Sc. in Medical Anatomy Scholar, Batch 2024, Faculty of Medical Science, Manipur International University, Manipur, India.
Dr. Prof. Harikumar Pallathadka
Vice-Chancellor, Manipur International University, Manipur, India
