Fig. 1

Pattern spectrum of VF defect in NMOSD-ON and IDON. A The distribution of patterns of VF defect in NMOSD-ON group at each follow-up. B The distribution of patterns of VF defect in IDON group at each follow-up. At 1 m, no central abnormality presented in NMOSD group while in IDON group 15.8% had this pattern (p = 0.01 with *). At ≥ 6 m, 4% in IDON group versus 19.6% in NMOSD-ON group failed the VF exam (p = 0.005 with **). No significant difference was found between the two groups at other time points (p > 0.05). NMOSD-ON: neuromyelitis optica spectrum disorder- optic neuritis, IDON: idiopathic optic neuritis, P: P value, *: P < 0.05, **: P < 0.01, onset: at onset of optic neuritis, 1 m: at 1 month after onset, 3 m: at 3 months after onset, ≥ 6 m: at 6–12 months after onset