[Study of diopters-cutting in treatment of PRK for myopia].

Purpose: To study a method of determining the diopters-cutting for photorefractive keratectomy (PRK) pre-operation.

Methods: By statistics, to analyze the differences of diopter between optometry of mydriasis and keratectomy in 143 cases 209 eyes of medium myopia with complete data recorded.

Result: The average diopter for optometry of mydriasis is -4.32 D, for keratectomy, -4.74 D. The average of differences is (0.42 +/- 0.173) D, P < 0.01.

Conclusion: The numerical value of diopter-cutting for operation should be higher than for optometry of mydriasis in treatment of PRK for myopia.