Ultimately improve the care of patients suffering from multiple sclerosis (1st cause of acquired non-traumatic disability in adults) and NMO spectrum diseases by using more efficient MRI sequences than the FLAIR sequence commonly used in detection of optic neuritis. In the literature, many studies have already focused on comparing the sensitivity of detection of white matter demyelination plaques using FLAIR, PSIR or DIR sequences. Some authors have shown better sensitivity of the PSIR sequence in the detection of demyelinating lesions of the marrow in multiple sclerosis compared to conventional sequences. Others have shown better performance of the combined use of PSIR and DIR sequences compared to the FLAIR sequence in the detection of cortical lesions in multiple sclerosis. However, in the context of optic neuritis, few comparative studies comparing these three sequences have been carried out: A 2022 study showed better diagnostic sensitivity of optic neuritis of the DIR sequence compared to the FLAIR sequence. A possible better diagnostic performance of a sequence not used in current practice in the detection of optic neuritis (PSIR and DIR sequences), would be possible to justify their use on a larger scale and ultimately improve patient care.