Clinical Differences Between Nonarteritic Anterior Ischemic Optic Neuropathy and Optic Neuritis in Chinese Patients: A Retrospective Comparative Case Series Study

The aim of this study is to compare the clinical features between nonarteritic anterior ischemic optic neuropathy (NAION) and optic neuritis (ON) in Chinese patients. The clinical features of 23 cases (23 eyes) of NAION and 62 cases (80 eyes) of ON, including their general conditions, manifestations, auxiliary examinations were retrospectively compared. Simultaneous onset of bilateral eye (29.03% vs. 0%, p=0.009) and pain on movement of the eyes (23.75% vs. 0%, p=0.022) were more common in ON patients in comparison to NAION patients. Ocular pain (32.5% vs. 4.35%, p=0.007) was higher in ON patients than that in NAION patients. Optic disc edema (100% vs. 62.5%, p<0.001), peripapillary hemorrhage (47.83% vs. 10%, p<0.001) and peripapillary hard exudates (17.39% vs. 1.25%, p=0.009) in NAION patients were more common compared to ON patients,. During fluorescein angiography, the rates of the partial or whole papillary hypofluorescent in early phase (65.21% vs. 22.86%, p<0.001), peripapillary choroidal filling delay (73.91% vs. 14.29%, p<0.001) and partial papillary hyperfluorescent in later phase (52.17% vs. 25.71%, p=0.019) were higher in NAION patients than those in ON patients. The clinical features of NAION and ON in Chinese patients reveal a surprising overlap and they still have some characteristic clinical features that can be utilized to differentiate the two diseases.