[Retreatment after excimer laser photorefractive keratectomy].

OBJECTIVE

To evaluate the efficacy and safety of reoperation of residual myopia because of regression, undercorrection with or without coexisting severe corneal haze after excimer laser photorefractive keratectomy (PRK).

METHODS

A VISK 20/20 excimer laser was used to treat myopia of -1.00 to -16.50 diopters (spherical equivalent) at corneal plane. 35 patients (51 eyes) who had residual myopia because of regression, undercorrection with or without coexisting severe corneal haze after initial PRK were retreated by using PRK and phototherapeutic keratectomy.

RESULTS

At 12 months after retreatment, the rates of uncorrected visual acuity more than or equal to 10/20 or 20/20 were 82.6% and 39.1% respectively, 100.0% and 50.0% in myopia up to -6.00 D, 73.3% and 33.3% in myopia of -6.25 to -16.50 D respectively. 86.3% of eyes were within +/- 1.00 diopters of desired emmetropia. Corneal haze after retreatment was not greater than that observed after initial procedures.

CONCLUSIONS

The residual myopia because of regression, undercorrection with or without severe corneal haze after initial PRK can be successfully retreated. Although the therapeutic result of retreatment of PRK is less successful than that of the initial procedure, retreatment appears to enhance it.