Cross-subject variability of the optic radiation anatomy: a large-scale analysis

Optic radiations are tracts of importance for neurosurgery, especially their path within the temporal lobe. Using an advanced analysis pipeline relying on probabilistic tractography and fiber clustering, we processed the diffusion MRI data of the 1065 subjects of the HCP cohort and reconstructed a reference optic radiation bundle. From it, we subsequently extracted the optic radiations of each subject to study the variability of their morphometry. We identified a higher variability of their rostral extent, with a significant left-right difference (median distance to the temporal pole +/- standard deviation: left: 28.8 +/- 2.3 mm, right: 29.2 +/- 2.1 mm, p=1.10-8).