Overcorrection, Undercorrection and Astigmatic Change after Excimer Laser Photorefractive Keratectomy of Myopia.
- Author:
Dong Suk SUH
1
;
Yeon Woo JEUNG
;
Young Ho HAHN
Author Information
1. Department of Ophthalmology, Kosin Medical College, Pusan, Korea.
- Publication Type:Original Article
- Keywords:
Astigmatism;
Excimer laser photorefractive keratectomy;
Overcorrection;
Undercorrection
- MeSH:
Astigmatism;
Incidence;
Lasers, Excimer*;
Myopia*;
Photorefractive Keratectomy*;
Postoperative Period
- From:Journal of the Korean Ophthalmological Society
1998;39(7):1380-1391
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
We have studied the overcorrection, undercorrection, astigmatic change and its incidence on time sequence after the excimer laser photorefractive keratectomy, and its relation with the degree of preoperative myopia, sex, and age. The study has been done with 429 eyes which we could assess for 6 months or more after excimer laser photorefractive keratectomy of myopia from July 1993 to march 1997. Overcorrection of more than -1D was common during the early postoperative periods and then gradually decreased with time. Overcorrection has been seen in 261 eyes(60.84%) after 1 month, but only 33 eyes(13.47%) after 1 year, and 13 eyes(11.02%) after 2 years. Undercorrection has been seen in 2 eyes(0.47%) after 1 month, but 25 eyes(10.20%) after 1 year, and 20 eyes(16.95%) after 2 years. Surgically induced astigmatism increased to 0.54+/-0.84D after 10 days and then decreased 0.19+/-0.75D after 12 months. Also, surgical induced astigmatism developed 1.13+/-1.10D in 247 eyes (57.58%) after 1 month, but decreased 0.89+/-0.45D in 107 eyes(43.67%) after 12 months. The occurrence of overcorrection and undercorrection was related to the severity of preoperative myopia(p<0.05), but with sex and age, it had no statistical correlation(p>0.05). The amount of postoperative astigmatism was related to preoperative astigmatism(p<0.05), but it had no statistical correlation with the degree of preoperative myopia, age, sex, and development and increase of surgically induced astigmatism(p>0.05).