From the Guidelines
Optic neuritis typically presents with painful visual loss, often affecting one eye, and can be associated with demyelinating diseases like multiple sclerosis. The clinical signs of optic neuritis include sudden vision loss, which can range from mild blurring to severe impairment, usually affecting one eye. Pain with eye movement is a characteristic feature, occurring in about 90% of cases, as noted in the context of its definition as an acute inflammatory condition of the optic nerve 1. Visual field defects are common, particularly central scotomas where patients have a blind spot in the center of their vision. Color vision is often affected, with patients reporting decreased color perception or desaturation. Pupillary examination may reveal a relative afferent pupillary defect (RAPD) in the affected eye, where the pupil dilates rather than constricts when light is moved from the unaffected to the affected eye. Fundoscopic examination may show optic disc swelling (papillitis) in about one-third of cases, while the remainder have a normal-appearing disc (retrobulbar neuritis).
Key considerations in the diagnosis and management of optic neuritis include:
- The use of MRI of the orbits and head without and with contrast as primary imaging studies for initial assessment, to evaluate for abnormal enhancement and signal changes within the optic nerve and to assess the brain for associated intracranial demyelinating lesions 1.
- Differentiation from other conditions such as ischemic optic neuropathy, which is usually unilateral, especially in patients with antiphospholipid antibodies 1.
- The potential association with demyelinating diseases like multiple sclerosis, necessitating neurological evaluation and possibly MRI imaging to assess for additional lesions in the central nervous system 1.
Given the potential for optic neuritis to be the initial manifestation of multiple sclerosis or other significant conditions, a thorough diagnostic workup, including complete ophthalmological evaluation and MRI, is crucial for appropriate management and to assess the risk of future episodes or progression to more severe neurological conditions 1.
From the Research
Clinical Signs of Optic Neuritis
The clinical signs of optic neuritis include:
- Pain on eye movement in one eye
- Subacute visual loss
- Weaker direct pupillary light reflex in the affected eye
- Mildly edematous optic disc in approximately one-third of patients
- Visual disturbance that resolves in 95% of cases 2
- Abrupt loss of vision, with recovery of vision almost never complete 3, 4
Diagnosis and Treatment
Diagnosis of optic neuritis is based on a constellation of symptoms and signs, and treatment strategies may include corticosteroids, therapeutic plasma exchange (PLEX), and other therapies 5, 2, 3, 4
- High-dosed intravenous methylprednisolone therapy may speed recovery but does not improve the final outcome 2
- Treatment escalation to PLEX may be beneficial for patients who do not respond adequately to corticosteroids 5
Prognosis and Recurrence
The visual prognosis and risk for recurrent injury may vary depending on the etiology of optic neuritis 6
- Rapid and accurate diagnosis of optic neuritis is critical for limiting vision loss, future neurologic disability, and organ damage 6