Optic neuritis
Background
- Inflammatory, demyelinating condition of the optic nerve highly associated with MS
- 50% will go on to develop MS
- Presenting feature of MS in 15-20% of patients
- Female and Caucasian predominance
- Age 20-50 years old
- More prevalent in populations located at higher latitudes
Causes
- Idiopathic
- Multiple sclerosis
- Postchildhood vaccination
- Viral infection
- Inflammation of structures contiguous with the optic nerve
- Other infections
- Sarcoidosis, uveitis
- Temporal arteritis
- Vasculitides
- Ischemic optic neuropathy
- Hypertensive retinopathy, papilledema
- Diabetes mellitus retinopathy
- Intracranial tumor, orbital tumor
- Glaucoma
Clinical Features
- Acute, usually monocular, vision loss occurring over days (occasionally over hours)
- May range from mildly reduced to no light perception whatsoever
- Retro-orbital headache
- Pain (esp with eye movement)
- Loss of color vision out of proportion to loss of visual acuity
- Pulfrich effect - swing object side to side like pendulum, but patient feels like the object is coming at them in elliptical fashion; suggestive of demyelination[1]
Differential Diagnosis
Acute Vision Loss (Noninflamed)
- Painful
- Arteritic anterior ischemic optic neuropathy
- Optic neuritis
- Temporal arteritis†
- Painless
- Amaurosis fugax
- Central retinal artery occlusion (CRAO)†
- Central retinal vein occlusion (CRVO)†
- High altitude retinopathy
- Open-angle glaucoma
- Posterior reversible encephalopathy syndrome (PRES)
- Retinal detachment†
- Stroke†
- Vitreous hemorrhage
- Traumatic optic neuropathy (although may have pain from the trauma)
†Emergent Diagnosis
Evaluation
Diagnosis on Physical Exam
- Red desaturation test
- Have patient look with one eye at a dark red object
- Test the other eye to see if the object looks the same color
- Affected eye often will see the red object as pink or lighter red
- Normal intraocular pressures
- Normal slit lamp exam (no evidence of uveitis)
- Afferent Pupillary Defect (APD)
- Optic disc swelling and edema (papillitis)
- Elevated optic nerve disk on ocular ultrasound = papilledema
- Increased ON sheath diameter > ~5mm measured 3mm behind globe on US[2]
Work-up
- MRI of brain and orbits with gadolinium, plus fat suppression
- CBC
- CMP
- ESR, CRP
- RPR, FTABS
- CXR
- May consider LP to rule out neuromyelitis optica (Consult with neuro regarding CSF and serum studies):
- Typically protein/glucose, gram stain/culture, cell count/differential
- Plus angioconverting enzyme, IgG indices, myelin basic protein, oligoclonal bands
- Plus SERUM IgG indices, oligoclonal bands, angioconverting enzyme, NMO antibodies
Management
- Consult neuro and ophthalmology with treatment focused on the underlying MS
- IV methylprednisolone, 1 g QD x3 days[3]
Disposition
- Admission
See Also
References
- ↑ O'Doherty M and Flitcroft DI. An unusual presentation of optic neuritis and the Pulfrich phenomenon. J Neurol Neurosurg Psychiatry. 2007 Aug; 78(8): 906–907.
- ↑ Shevlin C. Optic Nerve Sheath Ultrasound for the Bedside Diagnosis of Intracranial Hypertension: Pitfalls and Potential. http://www.criticalcarehorizons.com/optic-nerve-sheath-diameter-icp/
- ↑ Le Page, E. et al. Oral versus intravenous high-dose methylprednisolone for treatment of relapses in patients with multiple sclerosis (COPOUSEP): a randomised, controlled, double-blind, non-inferiority trial. Lancet. 2016 Jan 23;387(10016):340.
- Petzold A et al. The investigation of acute optic neuritis: a review and proposed protocol. Nat Rev Neurol. 2014 Aug;10(8):447-58.
- Voss E et al. Clinical approach to optic neuritis: pitfalls, red flags and differential diagnosis. Ther Adv Neurol Disord. 2011 Mar; 4(2): 123–134.