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Problems of refraction after photorefractive keratectomy
Journal of the American Optometric Association
|December 1, 1996
Summary
Refracting patients after excimer laser photorefractive keratectomy (PRK) can be challenging due to corneal haze and ablation zone issues. Experienced refractionists are crucial for accurate pre- and post-operative assessments in myopia correction.
Area of Science:
- Ophthalmology
- Refractive Surgery
- Corneal Surgery
Background:
- Excimer laser photorefractive keratectomy (PRK) is an increasingly accepted refractive procedure for myopia correction.
- PRK has been under clinical investigation since January 1992, presenting unique challenges in patient refraction.
Observation:
- A review of 971 eyes with myopia (-2.00 to -15.00 D) and at least 1-year follow-up was conducted.
- Data included pre-operative (manifest and cycloplegic) and post-operative (3-month) refractions.
Findings:
- Moderate to severe corneal haze degraded the retinoscopic reflex, causing refractive difficulty in seven eyes.
- Small or decentered ablation zones, excessive accommodation, refractive shifts, irregular astigmatism, and inaccurate autorefractometer readings complicated refraction.
Implications:
- Laser ablation alters corneal optical homogeneity, potentially leading to significant refractive errors.
- Accurate refraction in PRK patients necessitates meticulous and consistent evaluation by experienced professionals before and after treatment.