In vivo multimodal MRI of the healthy optic nerves

The optic nerve (ON) is implicated in a variety of neurological disorders but is challenging to study through magnetic resonance imaging due to its small size and jittering. In this study, we developed an acquisition protocol and analysis pipeline that enables to produce quantitative proton density (PD), macromolecular tissue volume (MTV), T2* and T1 maps of the ON from a 20-minute scan. Results show good scan-rescan reproducibility of ON values, and agreement with regional brain values. Significant differences in PD, MTV and T1 were observed between left-right ON measures, and left-right fronto-temporal white matter, which warrant further investigation.