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)<unk>  disc swelling and edema (papillitis)
Elevated<unk>  nerve disk on ocular ultrasound = papilledema
Increased ON sheath diameter > ~5mm measured 3mm behind globe on US
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
Affected eye often will see the red object as pink or lighter red
Elevated<unk>  nerve disk on ocular ultrasound = papilledema
Increased ON sheath diameter > ~5mm measured 3mm behind globe on US
MRI of brain and orbits with gadolinium, plus fat suppression
CBC
CMP
ESR, CRP
RPR, FTABS
CXR
May consider LP to rule out neuromyelitis<unk> a (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
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
Optic neuritis
Painful
Traumatic optic neuropathy
Arteritic anterior ischemic optic neuropathy
Vestibular neuritis
Endophthalmitis
Temporal arteritis†
Labyrinthitis