MOG and neuromyelitis optica: As temporal pRNFL thickness of MS-ON eyes does not differ significantly from temporal pRNFL thickness in neuromyelitis optica spectrum disorders (NMOSD) [11], the latter of which are known to result in severe atrophy [21] the similar outcome between temporal pRNFL thickness in MOG-ON and MS-ON may be due to relatively more severe temporal thinning in MS-ON rather than less severe temporal thinning in MOG-ON.