Optic neuritis is generally caused by demyelinating diseases, including common conditions such as neuromyelitis optica, multiple sclerosis, and retrobulbar neuritis. These diseases can severely impact the patient's vision and create significant burdens. Typically, examinations of the optic nerve are required, covering several aspects. First, an examination of the fundus is necessary, generally using an ophthalmoscope or other devices to observe the optic disc and surrounding blood vessels, which is very important. Second, a visual evoked potential test can be conducted. This test helps assess whether there is damage to the optic nerve and the severity of the damage. Third, it is necessary to complete an MRI of the optic nerve. Evaluations might include a lumbar puncture to analyze cerebrospinal fluid, and complete tests related to water channels, protein antibodies, oligoclonal bands, etc., to help confirm the diagnosis.