Etiology of Optic Neuritis
Optic neuritis is most common among adults 20 to 40 years. Most cases result from demyelinating disease, particularly multiple sclerosis Multiple Sclerosis (MS) Multiple sclerosis (MS) is characterized by disseminated patches of demyelination in the brain and spinal cord. Common symptoms include visual and oculomotor abnormalities, paresthesias, weakness... read more , in which case there may be recurrences. Optic neuritis is often the presenting manifestation of multiple sclerosis. Other causes include:
Neuromyelitis optica Neuromyelitis Optica Spectrum Disorder (NMOSD) Neuromyelitis optica spectrum disorder is a demyelinating disorder that predominantly affects the eyes and spinal cord but can affect other structures in the central nervous system (CNS) that... read more (NMO) (1 General references Optic neuritis is inflammation of the optic nerve. Symptoms are usually unilateral, with eye pain and partial or complete vision loss. Diagnosis is primarily clinical. Treatment is directed... read more )
Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) (2 General references Optic neuritis is inflammation of the optic nerve. Symptoms are usually unilateral, with eye pain and partial or complete vision loss. Diagnosis is primarily clinical. Treatment is directed... read more )
Infectious diseases (eg, viral encephalitis Encephalitis Encephalitis is inflammation of the parenchyma of the brain, resulting from direct viral invasion or occurring as a postinfectious immunologic complication caused by a hypersensitivity reaction... read more [particularly in children], sinusitis Sinusitis Sinusitis is inflammation of the paranasal sinuses due to viral, bacterial, or fungal infections or allergic reactions. Symptoms include nasal obstruction and congestion, purulent rhinorrhea... read more , meningitis Overview of Meningitis Meningitis is inflammation of the meninges and subarachnoid space. It may result from infections, other disorders, or reactions to drugs. Severity and acuity vary. Findings typically include... read more , tuberculosis Tuberculosis (TB) Tuberculosis is a chronic, progressive mycobacterial infection, often with an asymptomatic latent period following initial infection. Tuberculosis most commonly affects the lungs. Symptoms include... read more [TB], syphilis Syphilis Syphilis is caused by the spirochete Treponema pallidum and is characterized by 3 sequential symptomatic stages separated by periods of asymptomatic latent infection. Common manifestations... read more , human immunodeficiency virus Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection results from 1 of 2 similar retroviruses (HIV-1 and HIV-2) that destroy CD4+ lymphocytes and impair cell-mediated immunity, increasing risk of certain... read more [HIV])
Tumor metastasis to the optic nerve
Systemic lupus erythematosus
Chemicals and drugs such as lead. methanol, quinine, arsenic, ethambutol, and antibiotics cause optic neuropathies rather than true optic neuritis. TNF-alpha inhibitors and immune checkpoint inhibitors can cause optic neuritis.
Rare causes include pernicious anemia Autoimmune Metaplastic Atrophic Gastritis Autoimmune metaplastic atrophic gastritis is an inherited autoimmune disease that attacks parietal cells, resulting in hypochlorhydria and decreased production of intrinsic factor. Consequences... read more and systemic autoimmune diseases. Often, the cause remains idiopathic despite thorough evaluation.
1. Chen JJ, Pittock SJ, Flanagan EP, et al: Optic neuritis in the era of biomarkers. Surv Ophthalmol 65(1):12-17, 2020. doi: 10.1016/j.survophthal.2019.08.001
2. Chen JJ, Bhatti MT: Clinical phenotype, radiological features, and treatment of myelin oligodendrocyte glycoprotein-immunoglobulin G (MOG-IgG) optic neuritis. Curr Opin Neurol 33(1):47-54, 2020. doi: 10.1097/WCO.0000000000000766
Symptoms and Signs of Optic Neuritis
The main symptom of optic neuritis is vision loss, frequently maximal within several days and varying from a small central or paracentral scotoma to complete blindness. Most patients have mild eye pain, which often feels worse with eye movement.
The most characteristic findings include reduced visual acuity, a visual field deficit, and disturbed color vision (often out of proportion to loss of visual acuity). An afferent pupillary defect is usually detectable if the contralateral eye is unaffected or involved to a lesser degree. Testing of color vision is a useful adjunct, although 10% of males have congenital color blindness, producing false-positive results. In about two thirds of patients, inflammation is entirely retrobulbar, causing no visible changes to the optic nerve head. In the rest, disk hyperemia, edema in or around the disk, vessel engorgement, or a combination is present. A few exudates and hemorrhages may be present near or on the optic disk, but this is rare for most cases of optic neuritis.
Diagnosis of Optic Neuritis
Magnetic resonance imaging (MRI)
Optic neuritis is suspected in patients with characteristic pain and vision loss, particularly if they are young. Neuroimaging, preferably with gadolinium-enhanced MRI of the brain and orbits, is usually done and may show an enlarged, enhancing optic nerve. MRI may also help diagnose multiple sclerosis, myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and neuromyelitis optica (NMO). There is usually more extensive enhancement of the optic nerve(s) in NMO and MOGAD. Fluid attenuating inversion recovery (FLAIR) MRI sequences may show typical demyelinating lesions in a periventricular location if optic neuritis is related to multiple sclerosis. Spinal cord involvement can be seen in any of the demyelinating diseases but is usually more extensive in NMO and MOGAD. NMO and MOG antibodies in the serum should be checked for any atypical or severe optic neuritis.
Pearls & Pitfalls
Prognosis for Optic Neuritis
Prognosis depends on the underlying condition. Most episodes of typical optic neuritis improve spontaneously with significant recovery of vision in 2 to 3 months. The recurrence rate among patients with optic neuritis is variable and depends on the etiology. Patients with an underlying disease, such as NMO or MOGAD, have higher rates of recurrence in the same eye or in the other eye, and recovery of vision can be worse, especially for NMO (1 Prognosis reference Optic neuritis is inflammation of the optic nerve. Symptoms are usually unilateral, with eye pain and partial or complete vision loss. Diagnosis is primarily clinical. Treatment is directed... read more ). MRI is used to determine future risk of demyelinating disease, especially multiple sclerosis.
1. Beck RW, Cleary PA, Backlund JYC, Optic Neuritis Study Group: The course of visual recovery after optic neuritis: Experience of the optic neuritis treatment trial. Ophthalmology 127(4S):S174-S181, 2020. doi: 10.1016/j.ophtha.2020.01.027
Treatment of Optic Neuritis
Corticosteroids are an option, especially if multiple sclerosis or neuromyelitis optica are suspected. Treatment with methylprednisolone (1000 mg intravenously once a day) or the bioequivalent dose of oral prednisone (1250 mg once a day; [ 1 Treatment references Optic neuritis is inflammation of the optic nerve. Symptoms are usually unilateral, with eye pain and partial or complete vision loss. Diagnosis is primarily clinical. Treatment is directed... read more ]) for 3 days followed by prednisone (1 mg/kg orally once a day) for 11 days may speed recovery, but ultimate vision results are no different from those with observation alone for multiple sclerosis or idiopathic optic neuritis. Early high-dose corticosteroids may improve outcomes in atypical causes of optic neuritis, such as neuromyelitis optica (NMO) or myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD; [ 2 Treatment references Optic neuritis is inflammation of the optic nerve. Symptoms are usually unilateral, with eye pain and partial or complete vision loss. Diagnosis is primarily clinical. Treatment is directed... read more ]). Plasma exchange is often used for NMO attacks and is sometimes used for severe optic neuritis from other causes if the optic neuritis does not recover after high-dose corticosteroids. Treatment with low-dose oral prednisone alone does not improve vision outcome and may increase the rate of recurrent episodes. Low-vision aids (eg, magnifiers, large-print devices, talking watches) may be helpful. Multiple sclerosis disease-modifying treatments should be given to patients with multiple sclerosis, and NMO-specific treatments should be used in patients with NMO. MOGAD patients with relapsing disease may need chronic immunotherapy. It is important to note that patients with NMO and MOGAD should not be given certain multiple sclerosis disease-modifying agents, which may be ineffective or even worsen the outcome.
1. Morrow SA, Fraser JA, Day C, et al: Effect of treating acute optic neuritis with bioequivalent oral vs intravenous corticosteroids: A randomized clinical trial. JAMA Neurol 75(6): 690-696, 2018. doi: 10.1001/jamaneurol.2018.0024
2. Chen JJ, Pittock SJ, Flanagan EP, et al: Optic neuritis in the era of biomarkers. Surv Ophthalmol 65(1):12-17, 2020. doi: 10.1016/j.survophthal.2019.08.001
Optic neuritis is most common among adults 20 to 40 years.
The most common causes are demyelinating diseases, particularly multiple sclerosis, neuromyelitis optica (NMO), and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD), but infections, drugs, and toxins are other possible causes.
Findings include mild pain with eye movement, visual disturbances (particularly disproportionate loss of color vision), and afferent pupillary defect.
Do gadolinium-enhanced MRI of the brain and orbits. Do MRI of the spinal cord if multiple sclerosis is suspected.
Corticosteroids and other treatments can be given, particularly if demyelinating disease is suspected. Plasma exchange is often given for NMO attacks or severe attacks that are unresponsive to high-dose corticosteroids.
Drugs Mentioned In This Article
|A-Methapred, Depmedalone-40, Depmedalone-80 , Depo-Medrol, Medrol, Medrol Dosepak, Solu-Medrol
|Deltasone, Predone, RAYOS, Sterapred, Sterapred DS