How to Diagnose Optic Neuritis

Optic neuritis is an inflammation of the optic nerve that is frequently the result of diseases that remove its protective myelin layer. It is closely linked to multiple sclerosis and is commonly the first sign of MS.

Instructions

• 1

  Take the patient's history. The onset of optic neuritis usually begins with vision impairment in one eye but may affect both eyes on rare occasions. A change in color perception is a common early symptom of optic neuritis.

• 2

  Conduct a physical examination of the eyes. The pupillary response usually is decreased and a Marcus Gunn pupil or relative afferent pupillary defect is commonly seen. The visual acuity also is decreased, although the severity is highly variable.

• 3

  Perform specific vision tests. A Pelli-Robson chart measures the patient's sensitivity to contrast and an Ishihara color plate tests the patient's color vision. These results will frequently be below normal in patients with optic neuritis.

• 4

  Run laboratory tests to eliminate other possible diagnoses. Blood tests can exclude optic neuropathy and an analysis of the spinal fluid can detect MS. The presence of the neuromyelitis optica-IgG antibody is a specific marker for neuromyelitis optica.

• 5

  Take a Magnetic Resonance Imaging (MRI) scan. This is a highly sensitive test for observing the inflammation of the optic nerve and can rule out the possibility of a structural lesion. An MRI also is useful at this point in detecting demyelinative lesions in the brain for patients with MS.