2.11 Contact Lens Overwear and Contamination
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Presentation
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A patient who wears hard, impermeable contact 
lenses may come to the ED in the early morning 
complaining of severe eye pain, after he has 
fallen asleep with his lenses in or stayed up 
late, leaving his lenses in for more than 12 
hours. Extended-wear soft lenses can cause a 
similar syndrome when left in for days or 
contanimated with irritants. The patient may 
not be able to open his eyes for examination 
because of pain and blepharospasm. He may show 
obvious corneal injury, with signs of iritis 
and conjunctivitis, or show no visible findings 
at all without fluorescein staining.

What to do:
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- Instill topical anesthestic drops.
- Perform a complete eye exam including 
   pupillary reflexes, funduscopy, and 
   inspection of conjunctival sacs. Use a slit 
   lamp if available.
- If you see any ulcerations on the cornea, 
   call for ophthalmologic consultation right 
   away. Acanthameba infections from soft 
   lenses can damage the eye rapidly, and may 
   require excision and hospitalization.
- Instill fluorescein dye (use single-dose 
   dropper or wet a dyeimpregnated paper strip 
   and touch it to the tear pool in the lower 
   conjunctival sac), have the patient blink, 
   and examine under cobalt blue or ultraviolet 
   light for the green fluorescence of dye 
   bound to devitalized corneal epithelium. 
   This staining should demonstrate central 
   corneal uptake of fluorescein without 
   sharply demarcated borders.
- Sketch the area of corneal injury on the 
   patient record, rinse out the dye and 
   instill tobramycin or gentamycin ointment in 
   the lower conjunctival sac.
- Prescribe analgesics (e.g., naproxen, 
   ibuprofen, oxycodone) and give the first 
   dose.
- Instruct the patient to avoid wearing his 
   lenses until cleared by the ophthalmologist, 
   and to seek ophthalmologic followup within 
   one day.

What not to do:
---------------

- Do not discharge a patient with topical 
   anesthetic ophthalmic drops for continued 
   administration: they potentiate serious 
   injury.
- Do not let a patient re-use contaminated or 
   infected soft lenses.
- Do not patch contact lens abrasions or early 
   ulcerative keratitis.
- Do not prescribe antibiotic ointments that do 
   not provide prophylaxis against Pseudomonas 
   (e.g., erythromycin and sulfas).
- Do not use steroid-containing drops or 
   ointments.

Discussion
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Hard contact lenses and extended-wear soft 
lenses left in place too long deprive the 
avascular corneal epithelium of oxygen and 
nutrients from the tear film. This produces 
diffuse ischemia, which usually heals perfectly 
in a day, but can be exquisitely painful as 
soon as the lenses are removed. Soft lenses can 
absorb chemical irritants, allergens, bacteria 
and ameba if they soak in a contaminated 
cleaning solution. There are approximately 25 
million contact lens wearers in the US. Adverse 
reactions range from minor transient irritation 
to corneal ulceration and infection that may 
result in permanent loss of vision from corneal 
scarring. Pseudomonas is most commonly 
associated with contact lens-related keratitis. 
It is for this reason that the management of 
these cases should differ from routine care 
given to mechanical corneal abrasions not 
caused by contact lenses. Occlusive patching 
and corticosteroid medications favor bacterial 
growth and are therefore not recommended in the 
setting of contact lens use.

References:
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- Schein Oliver D: Contact lens abrasions and 
   the nonophthalmologist. *Am J Emerg Med*. 
   1993;11:606-608.

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