Ver el código de «Optic neuritis»

==Background==
[[File:Schematic diagram of the human eye en.png|thumb|Eye anatomy.]]
*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
**[[Measles]], [[mumps]], [[varicella zoster virus]], [[EBV]]
*Inflammation of structures contiguous with the optic nerve
**[[meningitis|Meninges]], [[orbital cellulitis|orbit]], [[sinusitis|sinuses]]
*Other infections
**[[Syphilis]], [[Tuberculosis]], Crypto
*[[Sarcoidosis]], uveitis
*[[Temporal arteritis]]
*[[vasculitis|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]]
*[[eye pain|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<ref>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.</ref>

==Differential Diagnosis==
{{Acute vision loss noninflamed DDX}}

==Evaluation==
[[File:PMC3379920 jovr-5-3-216-776-1-pbf1.png|thumb|MRI showing enhancement of the left optic nerve, which is typical of optic neuritis.]]
===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 pressure]]s
*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<ref>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/</ref>

===Work-up===
*[[brain MRI|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

==Disposition==
*Consult neuro and ophthalmology
*Inpatient admission for IV methylprednisolone, 1 g QD x3 days

==See Also==
*[[Multiple Sclerosis (MS)]]

==References==
<references/>
*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.

[[Category:Neurology]]
[[Category:Ophthalmology]]