Dr Agarwal's Eye Hospital and Eye Research Centre, Chennai, India.
Am J Ophthalmol. 2011 Oct;152(4):582-590.e2. doi: 10.1016/j.ajo.2011.03.019. Epub 2011 Jun 17.
To analyze the long-term safety profile, visual and refractive results, and incidence of complications between sub-Bowman keratomileusis with 90- and 100-μm flaps.
Prospective, randomized, comparative clinical study.
A total of 385 candidates (770 eyes) underwent bilateral, single-sitting, sub-Bowman keratomileusis, with flap creation (90 or 100 μm) on IntraLase 60-kHz (Abott Medical Optics) and ablation on Technolas 217z100 (Technolas PV) . Right and left eyes were randomized to undergo 90- or 100-μm flap procedures. Preoperative and postoperative assessment included uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refraction, and topographic analysis. All cases were followed up until 12 months after surgery. After excluding cases lost to follow-up, a final analysis of 368 patients was carried out (368 eyes in each of the 2 groups). The main outcome measures were BSCVA, UCVA, complication rates, and residual spherical equivalent refractive error.
The mean preoperative values were: spherical equivalent, -6.08 ± 2.7 diopters (D; 90-μm group) and -5.99 ± 2.8 D (100-μm group; P = .7); and logarithm of the minimal angle of resolution BSCVA, 0.01 ± 0.03 (90-μm group) and 0.01 ± 0.04 (100-μm group: P = .8). Postoperative 12-month values were: spherical equivalent, -0.02 ± 0.4 D (90-μm group) and -0.01 ± 0.4 D (100-μm group; P = .8); logarithm of the minimal angle of resolution BSCVA, -0.05 ± 0.07 (90-μm group) and -0.04 ± 0.07 (100-μm group; P = .8); and logarithm of the minimal angle of resolution UCVA, 0.012 ± 0.01 (90-μm group) and 0.017 ± 0.02 (100-μm group; P = .2). No loss of BSCVA was seen in any case. The efficacy indices were 1.039 ± 0.21 (90-μm group) and 1.014 ± 0.24 (100-μm group; P = .2); safety indices were 1.163 ± 0.21 (90-μm group) and 1.158 ± 0.22 (100-μm group; P = .6); and vision difference indices were 0.09 ± 0.14 (90-μm group) and 0.10 ± 0.15 (100-μm group; P = .1). Both groups had a low but comparable incidence of diffuse lamellar keratitis and microstriae. However, the incidence of microstriae (although visually asymptomatic) was significantly higher in ablation with spherical equivalent of -9 D or more compared with lesser ablations (6.7% vs 0.8%; P < .001).
The 1-year follow-up of femtosecond sub-Bowman keratomileusis with 90- and 100-μm flaps suggests that both the flap options have comparable outcomes.
分析 90μm 和 100μm 瓣下角膜磨镶术的长期安全性、视力和屈光结果以及并发症发生率。
前瞻性、随机、对照临床研究。
共 385 名候选者（770 只眼）接受了双侧单次的 SUB-Bowman 角膜磨镶术，使用 IntraLase 60kHz（Abbott Medical Optics）制作 flap，在 Technolas 217z100（Technolas PV）上进行消融。右眼和左眼随机接受 90μm 或 100μm flap 手术。术前和术后评估包括未矫正视力（UCVA）、最佳矫正视力（BSCVA）、屈光度和地形分析。所有病例均随访至术后 12 个月。排除失访病例后，对 368 例患者（每组 368 例）进行了最终分析。主要观察指标为 BSCVA、UCVA、并发症发生率和残余等效球镜屈光误差。
平均术前值为：等效球镜度-6.08±2.7 屈光度（90μm 组）和-5.99±2.8 屈光度（100μm 组；P=.7）；最小分辨角对数视力 BSCVA 为 0.01±0.03（90μm 组）和 0.01±0.04（100μm 组；P=.8）。术后 12 个月值为：等效球镜度-0.02±0.4 屈光度（90μm 组）和-0.01±0.4 屈光度（100μm 组；P=.8）；最小分辨角对数视力 BSCVA 为-0.05±0.07（90μm 组）和-0.04±0.07（100μm 组；P=.8）；最小分辨角对数 UCVA 为 0.012±0.01（90μm 组）和 0.017±0.02（100μm 组；P=.2）。在任何情况下均未出现 BSCVA 损失。功效指数为 1.039±0.21（90μm 组）和 1.014±0.24（100μm 组；P=.2）；安全性指数为 1.163±0.21（90μm 组）和 1.158±0.22（100μm 组；P=.6）；视力差异指数为 0.09±0.14（90μm 组）和 0.10±0.15（100μm 组；P=.1）。两组弥漫性层间角膜炎和微条纹的发生率均较低，但比较低。然而，在等效球镜度为-9D 或更高的消融中，微条纹的发生率（尽管在视觉上无症状）明显高于较低的消融（6.7%对 0.8%；P<.001）。
1 年随访显示，90μm 和 100μm 瓣下角膜磨镶术具有相似的结果。
