Cause:H. simplex(50%) and other viruses (H. zoster, adenovirus), contact lenses esp overnight use (Nejm 1989;321:773, 779) and associated fusarium (Jama 2006;295:2867), exanthems, bacterial, chronic topical anesthetic use (Nejm 1968;279:396)

1% of remainder after FB

Sx/Si:Photophobia, FB sensation; corneal ulcer (dendritic if herpetic), mixed type injection, PERRLA, corneal wbc infiltrates

Achronic corneal neurotrophic ulcers

Rx:

When H. simplex, 1st, trifluridine (Viroptic) i gtt 1% solution q2h; 2nd, Ara A; then consider prophylaxis w acyclovir 400 mg po bid × 12 mos, which decr recurrence rates from ~35% to <20% (Nejm 1998;339:300)

When bacterial, appropriate antibiotics; mydriatics to relax ciliary spasm

in chronic corneal neurotrophic ulcers: corneal transplant and/or perhaps topical nerve growth factor (Nejm 1998;338:1174, 1222)