Clinical implications of sagittal stratum damage: Laterality, neuroanatomical developmental considerations, and functional outcomes.

Background: The sagittal stratum (SS) is an important white matter (WM) structure that provides the anatomic substrate for cortico-cortical and cortico-subcortical axial interconnections necessary to overcome sensory, cognitive and motor processes. SS damage due to diseases or surgical lesions often results in significant functional losses, mainly involving serious language, visual processing, and cognitive deficits. These risks are maximized in older adults because of age-related WM degeneration. Methods: In this comprehensive review, the research aims to synthesize research conducted on anatomy-functional roles that concern the SS, damage, and surgical outcomes. This would then separate studies that employed high neuroimaging advanced techniques, such as diffusion tensor imaging, combined with intraoperative mapping performed during awake surgery. Key attention areas will, therefore, be trajectories pointing toward lateralization of the SS tracts, age-related vulnerabilities, and the effectiveness of surgical strategies in preserving SS integrity. Results: The review indicates that the pattern of SS damage is associated with lateralized deficits stemming from left-sided lesions, while language and vision are affected by right-sided. Older adults, already bearing significant WM degeneration, therefore, stand at a significantly greater risk of overall cognitive decline from compounding losses due to SS damage. However, advanced neuroimaging tools and refined surgical techniques have made the preservation of SS pathways much more effective, reducing long-term deficits. Conclusion: Intraoperative preservation of SS integrity is crucial for the reduction of functional deficits and enhancement of the outcomes. Customized surgical techniques that consider tract lateralization and age-related changes are required. Further research in this area is needed.