Long-Term Clinical Evaluation Of Laser In Situ Keratomileusis For Myopia

Objective: To evaluate the long-term outcomes of laser in situ keratomileusis (LASIK) for myopia and analyse the factors influencing outcomes.Methods: The study included 37 patients (71 eyes) from January to December, 2002 at the laser treatment center, First Affiliated Hospital of Dalian Medical University who has undergone LASIK with the German Eagle Wavelight excimer laser. Refraction at-2.25D ~-11.75D, the average refraction was -6.06±3.2D. The average age was 25.42±5.97. 18were male, 35eyes, accounting for 49.30%; female 19, 36eyes, accounting for 50.70%.The main outcome measures were visual acuity, refraction, best corrected visual acuity (BCVA), postoperative complications of extremely relevant factors on the impact of outcomes.Results: (1) The mean uncorrected visual acuity (UCVA) of all eyes after surgery for ten years was 0.82±0.28.The postoperative UCVA of all eyes had obvious elevation compared with the preoperative UCVA. At 10 years, 49.19% of eyes had uncorrected visual acuity of l.0 or better and 83.2% of 0.5 or better, the effective index of visual acuity was 0.86. (2) The mean refractive of all eyes after surgery for ten years was -0.79±1.42D. All of the postoperative refraction had obvious descent. At 10 years, 72.5% of all eyes were within -1.00 D and 50.7% were within -0.50 D. (3) The mean best corrected visual acuity (BCVA) for ten years was 0.97±0.14D, the effective index of visual acuity was 1.02. At ten years 70.42% (50/71) of all eyes postoperative best corrected visual acuity(BCVA) remained unchanged compared with preoperative BCVA, 18.31% increase in 1 line (13/71); 8.45% (6/71)lost 1 line ; 2.82% (2/71)decreased by 2 lines or more. postoperative complications for ten years were dry eyes(6 eyes), one Keratoconus after 10 years. (4) After ten years 28.17% (20/71) appeared refractive regression, was positively correlated with preoperative spherical equivalent refraction, with the changes in corneal curvature.Conclusion: (1) At ten years, LASIK treatment for myopia is predictability, safety and predictable. (2) After surgery, some eyes have refractive regression with time. Preoperative spherical equivalent refraction and the changes in corneal curvature were the related factors. (3) After ten years found that cases of secondary keratoconus, although the details of the preoperative screening, intraoperative flap thickness produced a good and sufficient stromal bed thickness, and regular follow-up after secondary prevention such as keratoconus Important measures, but its etiology still need further study.