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adverse effects if given to an individual with a fluorescein negative eye disorder for no
more than three days.
Not all ruptured globes are obvious. An occult ruptured globe may be suspected
on the basis of severe blunt trauma, a history of an impaling injury or one which results
from metal-on-metal hammering, the presence of dark uveal tissue exposed at the limbus,
a distorted pupil, or a decrease in vision. An occult ruptured globe also entails the
possibility of endophthalmitis and is treated in the same manner as an obvious open
globe.
If there is no history of trauma, the next important diagnostic step is a fluorescein
stain. Should this test reveal an epithelial defect, the diagnostic possibilities include a
corneal ulcer, a corneal erosion, or herpes simplex keratitis. The mechanism for corneal
ulcer occurrence in the absence of a history of trauma is usually contact lens wear. If a
corneal ulcer is diagnosed based on an epithelial defect and a white or gray spot on the
cornea, treat as described above for a post-traumatic corneal ulcer. Discontinue contact
lens wear in BOTH eyes immediately and use glasses for refractive correction because
the infection may be the result of contaminated lens solutions or cases.
The diagnosis of corneal erosion is made when there is an epithelial defect
resembling a traumatic abrasion in the absence of a history of trauma. There is often a
history of previous episodes. The onset of pain usually occurs when the eye is first
opened in the morning. Treatment is as for a corneal abrasion. Corneal erosions are often
slower to resolve than corneal abrasions because the sloughing epithelial tissue impedes
healing of the corneal epithelium. The loose and mobile layer of sloughing corneal
epithelium may need to be removed by a moistened cotton-tipped applicator after topical
anesthesia if corneal healing is not progressing.
Herpes simplex keratitis is diagnosed by a typical dendritic figure on fluorescein
staining and the absence of a history of trauma. There is often a history of previous
episodes. Urgently evacuate a patient with this finding, since this disorder does not
respond to topical antibiotics.
If the fluorescein stain reveals no epithelial defect, the next useful bit of
diagnostic information is the response of the eye pain to topical anesthesia. Relief of eye
pain by topical anesthesia indicates that the pain is due to an ocular surface disease, some
of which will be discussed below. If the pain is NOT relieved by topical anesthesia, then
the next item of information needed is the size of the pupil in the affected eye compared
to the fellow eye. If the pupil is dilated, then the likely diagnosis is angle-closure
glaucoma (ACG). ACG usually occurs in patients over 40, is accompanied by a decrease
in vision, and often by a history of previous episodes of eye pain. Treatment is with
pilocarpine 2%, 1 drop every 15 minutes x 4 doses in the affected eye, then four times a
day in BOTH eyes. Give acetazolamide 250 mg 4 times a day if available. Urgently
evacuate the affected individual for definitive treatment with a laser iridotomy, since
markedly elevated intraocular pressures may result in permanent damage to the optic
nerve in 24 hours or less.
If the pain is NOT relieved by topical anesthesia, and the pupil is normal or
constricted (miotic), then the likely diagnosis is either iritis or scleritis. Both diseases are
often associated with systemic inflammatory disorders and may be vision threatening if
not treated promptly and aggressively. Initiate treatment with prednisolone 1%, 1 drop
every hour around the clock until evacuated. Also instill scopolamine 0.25%, 1 drop
