el-Maghraby A, Salah T, Polit F, Ballew C, DeLuca M, Raanan M G
El-Maghraby Eye Hospital, Jeddah, Saudi Arabia.
J Cataract Refract Surg. 1996 Jan-Feb;22(1):51-8. doi: 10.1016/s0886-3350(96)80270-7.
To compare the safety and efficacy of radial keratotomy (RK) and photorefractive keratectomy (PRK) to correct myopia.
In this randomized, prospective, parallel-group study, 33 patients with bilateral myopia of 1.00 to 5.00 diopters (D) had PRK in one eye and RK in the other. The order of surgeries and treatment assignments were randomized, and the bilateral surgeries were within 1 week for each patient. Data were collected using standardized procedures. Clinical measurements and satisfaction surveys were taken in masked fashion.
Eyes that had PRK had statistically significantly more residual myopia than RK-treated eyes at 3, 6, and 12 months postoperatively. This result was attributed to the use of an older excimer laser PRK algorithm that was used at the initiation of the study. No eye that had PRK was overcorrected by 0.50 D or more at 1 year postoperatively, while seven eyes that had RK were overcorrected by at least 0.50 D and six were overcorrected by 1.00 D. Eyes that had PRK had a statistically significant mean shift in the myopic direction between 6 and 12 months postoperatively; two RK eyes had hyperopic shifts of 1.00 D. Three RK eyes and two PRK eyes failed to achieve an uncorrected visual acuity of 20/40 or better by 12 months postoperatively. No eye lost any best corrected visual acuity.
The two procedures were comparably safe and effective in treating mild to moderate myopia under this protocol. Eyes that had PRK were somewhat more myopic at 1 year after surgery, attributable to the older PRK ablation algorithm. Adoption of newer (current) laser algorithms has improved the predictability of PRK. There was also evidence of reduced variability of outcome in the PRK group. The PRK eyes did not exhibit hyperopic shifts during the 1 year follow-up.
比较放射状角膜切开术（RK）和准分子激光原位角膜磨镶术（PRK）矫正近视的安全性和有效性。
在这项随机、前瞻性、平行组研究中，33例双眼近视度数为1.00至5.00屈光度（D）的患者，一只眼睛接受PRK，另一只眼睛接受RK。手术顺序和治疗分配是随机的，每位患者的双眼手术在1周内完成。使用标准化程序收集数据。临床测量和满意度调查以盲法进行。
术后3个月、6个月和12个月时，接受PRK的眼睛比接受RK治疗的眼睛有统计学上显著更多的残余近视。这一结果归因于研究开始时使用的较旧的准分子激光PRK算法。术后1年，没有接受PRK的眼睛出现0.50 D或更高的过矫，而7只接受RK的眼睛过矫至少0.50 D，6只过矫1.00 D。接受PRK的眼睛在术后6个月至12个月之间近视方向有统计学上显著的平均偏移；2只RK眼睛有1.00 D的远视偏移。术后12个月时，3只RK眼睛和2只PRK眼睛未达到20/40或更好的未矫正视力。没有眼睛丧失任何最佳矫正视力。
在此方案下，这两种手术在治疗轻度至中度近视方面具有相当的安全性和有效性。接受PRK的眼睛在术后1年时近视程度略高，这归因于较旧的PRK消融算法。采用更新的（当前）激光算法提高了PRK的可预测性。也有证据表明PRK组的结果变异性降低。PRK眼睛在1年随访期间未出现远视偏移。
