Sedghipour M R, Sorkhabi R, Mostafaei A
Nikoukari Ophthalmology University Hospital, Tabriz University of Medical Sciences, Tabriz, Iran.
Clin Ophthalmol. 2012;6:199-204. doi: 10.2147/OPTH.S24923. Epub 2012 Jan 31.
Although there have been many studies of the efficacy and safety of wavefront- guided (WF) and cross-cylinder photorefractive keratectomy (PRK), there are few studies on moderate-to-high astigmatism cases. The aim of this study was to assess and compare the efficacy of WF and cross-cylinder PRK in moderate-to-high astigmatism.
In a comparative cohort, the results of two before-and-after clinical trials conducted on moderate-to-high astigmatism were studied. In the first trial, 50 eyes of 25 patients with stable refraction were enrolled in a before-and-after clinical trial to undergo WF PRK using the VISX™ (VISX Inc, Santa Clara, CA) system. The second clinical trial enrolled 48 eyes of 24 patients with stable refraction and moderate-to-high astigmatism to undergo PRK by the cross-cylinder method using a NIDEK EC-5000 excimer laser system (NIDEK Co Ltd, Gamagori, Japan).
After 6 months, 80% of the eyes in the WF group had uncorrected visual acuity of 20/20 or better compared to 40% in the cross-cylinder group. Only one eye in the cross-cylinder group and no eyes in the WF group lost more than one line of best corrected visual acuity (BCVA) after 6 months of treatment. No treated eyes in either group lost more than two lines of BCVA. The percentage of eyes with no change in BCVA was 54% and 58.3% in the WF and cross-cylinder groups, respectively. Mean postoperative absolute changes in total root-mean-square higher order aberrations in the WF group and cross-cylinder group were 0.05 ± 0.22 μm and 0.17 ± 0.20 μm, respectively (P < 0.001).
Both methods of PRK, using the NIDEK EC-5000 and VISX excimer laser systems, are effective for correcting moderate-to-high astigmatism. The WF approach appeared more successful in improving the refractive results.
尽管已有许多关于波前引导（WF）和交叉柱镜准分子激光角膜切削术（PRK）疗效和安全性的研究，但针对中高度散光病例的研究较少。本研究的目的是评估和比较WF和交叉柱镜PRK治疗中高度散光的疗效。
在一个比较队列中，研究了两项针对中高度散光进行的前后对照临床试验的结果。在第一项试验中，25例屈光稳定的患者的50只眼纳入前后对照临床试验，使用VISX™（VISX公司，加利福尼亚州圣克拉拉）系统进行WF PRK。第二项临床试验纳入了24例屈光稳定且有中高度散光的患者的48只眼，使用NIDEK EC - 5000准分子激光系统（NIDEK有限公司，日本蒲郡）通过交叉柱镜法进行PRK。
6个月后，WF组80%的患眼裸眼视力达到20/20或更好，而交叉柱镜组为40%。交叉柱镜组仅有1只眼，WF组无眼在治疗6个月后最佳矫正视力（BCVA）下降超过1行。两组中接受治疗的患眼BCVA下降均未超过2行。WF组和交叉柱镜组BCVA无变化的患眼百分比分别为54%和58.3%。WF组和交叉柱镜组术后总均方根高阶像差的平均绝对变化分别为0.05±0.22μm和0.17±0.20μm（P<0.001）。
使用NIDEK EC - 5000和VISX准分子激光系统的两种PRK方法对于矫正中高度散光均有效。WF方法在改善屈光结果方面似乎更成功。
