OBJECTIVETo investigate the relationship between various factors and the undercorrection after laser in situ keratomileusis (LASIK).

METHODSOf 1 391 eyes (696 cases), the undercorrection eyes grouped by left or right eye were analyzed by Chi-square test and logistic regression analysis based on age, sex, occupation, address, family history of myopia and all ophthalmologic examination results before and after LASIK.

RESULTSThe results of logistic regression analysis showed that the undercorrection after LASIK of both groups was related to four factors: the duration of myopia (left eye OR = 1.076, 95% CI: 1.030 - 1.124; right eye OR = 1.093, 95% CI: 1.046 - 1.142), preoperative refractive power (left eye OR = 7.799, 95% CI: 1.755 - 34.654; right eye OR = 28.823, 95% CI: 5.750 - 144.467), preoperative best corrected vision (left eye OR = 0.000, 95% CI: 0.000 - 0.262; right eye OR = 0.000, 95% CI: 0.000 - 0.144) and the corneal thickness (left eye OR = 0.976, 95% CI: 0.965 - 0.987; right eye OR = 0.975, 95% CI: 0.964 - 0.986).

CONCLUSIONLonger duration of myopia and the more refractive power seemed to be the risk factors, while the better corrected vision and the thicker thickness of cornea the protect factors of undercorrection after LASIK.

Adolescent ; Adult ; China ; epidemiology ; Female ; Humans ; Keratomileusis, Laser In Situ ; statistics & numerical data ; Logistic Models ; Male ; Middle Aged ; Multivariate Analysis ; Myopia ; epidemiology ; surgery ; Risk Factors ; Treatment Failure ; Visual Acuity

PURPOSE: This purpose of this report was to study trends in cataract and refractive surgeries conducted during the past twelve years and to compare results to previous reports from the ASCRS and New Zealand (NZ) in order to forecast future medical services. METHODS: We surveyed members of the Korean Society of Cataract and Refractive Surgery (KSCRS) every year from 1995 to 2006, and studied changes in cataract and refractive surgeries (RS). RESULTS: The duration of hospitalization has been gradually decreasing to the point that a one day hospitalization following surgery has become common. The rate of topical anesthesia use has significantly increased since 1998. Sutureless incision methods are now commonly practiced. The use of acryl IOL as an optic material has been gradually increasing for cataract surgeries. KSCRS members showed an interest in the special intraocular lenses as multifocal IOL. While Excimer laser PRK was the most popular refractive surgery during the first stage, KSCRS members increasingly prefer LASIK to the Excimer laser PRK. Regression of the corrected visual acuity, dry eye, night halo, and flashes were the most common complications following refractive surgeries. Medical disputes related to PRK and LASIK have been gradually increasing throughout the study period. CONCLUSIONS: We confirm that the KSCRS practice styles for cataract and RS are similar to those of the ASCRS and NZ. We infer a world-wide trend from the comparison of these three societies.
Adult ; Cataract Extraction/statistics & numerical data/*trends ; Humans ; Keratomileusis, Laser In Situ/statistics & numerical data/trends ; Laser Therapy/statistics & numerical data/trends ; Lasers, Excimer ; Lenses, Intraocular/statistics & numerical data/trends ; Middle Aged ; Ophthalmology/statistics & numerical data/*trends ; Photorefractive Keratectomy/statistics & numerical data/trends ; Professional Practice/statistics & numerical data/*trends ; Questionnaires ; Refractive Surgical Procedures/statistics & numerical data/*trends ; Republic of Korea ; Societies, Medical

This study evaluated the visual quality after wavefront-guided laser in situ keratomileusis (LASIK) for treating myopia. Thirty-two eyes with moderate myopia (-5.78~-2.17D) and 25 eyes with high myopia (-7.78~-6.17D) were prospectively reviewed. The contrast sensitivity (CS), glare and the total higher order aberrations (HOA) were measured before and 1 week, 1 month and 2 months after LASIK. The pupil diameter was measured at day- and night-time illumination. The CS and glare at all spatial frequencies were not reduced after wavefront-guided LASIK (p<0.05) and the difference between the moderate and high myopia group was not significant. No significant correlation was found between the amounts of myopia and the postoperative CS (p>0.05). The area under the log contrast sensitivity function (AULCSF) showed no correlation with the total HOA (r2=-0.071, p=0.612, between the daytime AULCSF and the total HOA with a 4 mm entrance pupil, r2=-0.176, p=0.260, between the nighttime AULCSF and the total HOA with a 6 mm entrance pupil). There was no decrease in CS and glare after wavefront-guided LASIK for myopia. In conclusion, wavefront-guided LASIK based on the individual ablation patterns is a good option for refractive surgery to improve the visual quality in both moderate and high myopia cases.
Adult ; Comorbidity ; Female ; Humans ; Keratomileusis, Laser In Situ/*statistics and numerical data ; Korea/epidemiology ; Male ; Myopia/*diagnosis/epidemiology/*surgery ; Prognosis ; Recovery of Function ; Research Support, Non-U.S. Gov't ; Treatment Outcome ; Vision Disorders/*diagnosis/epidemiology/*prevention and control ; *Vision Tests ; *Visual Acuity