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Inflammation-related scarring after photorefractive keratectomy.

PURPOSE
To study two cases of corneal scarring due to trauma (one case) and infection (one case) unrelated to a previous photorefractive keratectomy (PRK) for the correction of myopia.


METHODS
The patients are part of an Institutional Review Board-approved study of the safety and efficacy of PRK. Both patients underwent bilateral, nonsimultaneous corneal ablation based on preoperative spherical equivalent.


RESULTS
Seven months after PRK, the first patient sustained an alkali burn in one eye that caused severe corneal scarring and myopic regression. The other patient developed bilateral keratoconjunctivitis, more intense in the right eye (1 month after the operation) than in the left eye (4 months after the operation). This right eye subsequently developed diffuse scarring and loss of visual acuity.


CONCLUSION
Patients who have undergone PRK may develop severe corneal scarring after relatively mild ocular traumas or infections.