Ophthalmic Research Center, Labbafinejad Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Ophthalmology. 2013 Feb;120(2):252-9. doi: 10.1016/j.ophtha.2012.07.090. Epub 2012 Oct 18.
To compare the outcomes of 2 techniques (Anwar vs. Melles) of deep anterior lamellar keratoplasty (DALK) in patients with keratoconus.
Randomized, double-blind clinical trial.
Fifty-seven eyes of 57 patients 20 to 35 years of age were enrolled.
Patients with clinical diagnosis of keratoconus who were contact lens intolerant and whose corrected distance visual acuity (CDVA) was less than 20/80 were enrolled. Eligible eyes were allocated randomly into 2 groups: the Anwar technique (23 eyes) or the Melles technique (25 eyes).
The primary outcome measure was CDVA. Secondary outcomes were spherical equivalent, contrast sensitivity, corneal aberrations, corneal biomechanical properties, endothelial cell count, and central corneal thickness. All outcomes were compared 15 months after surgery.
The CDVA was 0.17 ± 0.09 logarithm of the minimum angle of resolution (logMAR) units and 0.18 ± 0.11 logMAR units in the Anwar and Melles groups, respectively (P = 0.803). Spherical equivalent was -1.82 ± 2.7 diopters (D) and -2.69 ± 3.94 D in the Anwar and Melles groups, respectively (P = 0.155). Overall, the difference in photopic and mesopic contrast sensitivity function between the 2 groups was statistically significant (P<0.05). There was no significant difference between 2 groups in total and higher-order aberrations up to the fifth order (P>0.05 for all parameters). Corneal hysteresis was not significantly different between the 2 groups (9.9 ± 0.8 vs. 9.9 ± 0.6; P = 0.606). The corneal resistance factor was 10.02 ± 0.8 and 10.13 ± 0.76 (P = 0.509). There was no significant difference in percentage of endothelial cell loss between the 2 groups (1 ± 2% vs. 1 ± 3% in the Anwar and Melles groups, respectively; P = 0.869). Mean central corneal thickness was 525.56 ± 47.87 μm versus 504.64 ± 54.20 μm in the Anwar and Melles groups, respectively (P = 0.155).
The Anwar and Melles techniques of DALK have comparable visual acuity and refractive outcomes, aberrometric profiles, biomechanical properties, corneal thicknesses, and endothelial cell densities. However, patients who underwent the Anwar technique showed better contrast sensitivity.
比较 2 种深板层角膜移植术（DALK）技术（Anwar 与 Melles）治疗圆锥角膜的效果。
随机、双盲临床试验。
57 名年龄在 20 至 35 岁之间的圆锥角膜患者的 57 只眼入选。
纳入对接触镜不耐受且矫正视力（CDVA）低于 20/80 的临床诊断为圆锥角膜的患者。将符合条件的眼睛随机分配到 2 组：Anwar 技术（23 只眼）或 Melles 技术（25 只眼）。
主要观察指标为 CDVA。次要观察指标为球镜等效值、对比敏感度、角膜像差、角膜生物力学特性、内皮细胞计数和中央角膜厚度。所有结果均在术后 15 个月进行比较。
Anwar 组和 Melles 组的 CDVA 分别为 0.17±0.09 最小分辨角对数（logMAR）单位和 0.18±0.11 logMAR 单位（P=0.803）。Anwar 组和 Melles 组的球镜等效值分别为-1.82±2.7 屈光度（D）和-2.69±3.94 D（P=0.155）。总体而言，2 组间明视和中视对比敏感度函数的差异具有统计学意义（P<0.05）。2 组间总高阶像差至第 5 阶的差异均无统计学意义（所有参数 P>0.05）。2 组间角膜滞后量无显著差异（9.9±0.8 与 9.9±0.6；P=0.606）。角膜阻力因子分别为 10.02±0.8 和 10.13±0.76（P=0.509）。2 组间内皮细胞丢失百分比无显著差异（Anwar 组和 Melles 组分别为 1±2%和 1±3%；P=0.869）。中央角膜厚度分别为 525.56±47.87 μm 和 504.64±54.20 μm（P=0.155）。
Anwar 和 Melles 技术的 DALK 具有相似的视力和屈光效果、像差特征、生物力学特性、角膜厚度和内皮细胞密度。然而，接受 Anwar 技术的患者表现出更好的对比敏感度。
