Arbelaez Maria Clara, Vidal Camila, Arba-Mosquera Samuel
Muscat Eye Laser Center, Muscat, Sultanate of Oman.
Invest Ophthalmol Vis Sci. 2008 Dec;49(12):5287-94. doi: 10.1167/iovs.08-2176. Epub 2008 Jul 24.
To compare the clinical outcomes of aberration-free ablation profiles based on the normal corneal vertex (CV) and the pupil center (PC) in relation to laser in situ keratomileusis. Aberration-free aspheric ablation treatments were performed in all cases.
Two myopic astigmatism groups (CV centered using the offset between pupil center and normal corneal vertex and PC centered using the pupil center) comprising 24 and 29 eyes (16 and 19 patients), respectively, with a 6-month follow-up, were included. All enrolled eyes had <0.65 mum RMS-higher order aberration (HOA) for 6.00 mm analysis diameter and pupillary offset >200 mum. In all cases, standard examinations, and preoperative and postoperative wavefront analysis were performed. Custom ablation software was used to plan aberration-free aspheric treatments and a flying spot excimer laser system was used to perform ablations. The clinical outcomes were evaluated for predictability, refractive outcome, safety, ocular wavefront aberration, and asphericity.
Of the CV eyes, 38% had improved best spectacle-corrected visual acuity (BSCVA) compared with 24% of the PC eyes (comparison CV/PC P = 0.38). Induced ocular coma was on average 0.17 mum in the CV group and 0.26 mum in the PC group (comparison CV/PC P = 0.01 favoring CV). Induced ocular spherical aberration was on average +0.01 mum in the CV group and +0.07 mum in the PC group (comparison CV/PC P = 0.05 favoring CV). Change in asphericity was on average +0.56 in the CV group and +0.76 in the PC group (comparison CV/PC P = 0.05 favoring CV). No significant shift was observed in the pupillary offset after treatments.
In myopic eyes with moderate to large pupillary offset, CV-centered treatments performed better in terms of induced ocular aberrations and asphericity, but both centrations were identical in photopic visual acuity.
比较基于正常角膜顶点（CV）和瞳孔中心（PC）的无像差消融模式在准分子原位角膜磨镶术（LASIK）中的临床效果。所有病例均采用无像差非球面消融治疗。
纳入两组近视散光患者，分别为24只眼（16例患者）以瞳孔中心与正常角膜顶点的偏移量为中心（CV组）和29只眼（19例患者）以瞳孔中心为中心（PC组），随访6个月。所有纳入的眼睛在6.00mm分析直径下的均方根高阶像差（HOA）<0.65μm，瞳孔偏移>200μm。所有病例均进行标准检查以及术前和术后波前分析。使用定制消融软件规划无像差非球面治疗，并使用飞点准分子激光系统进行消融。评估临床效果的可预测性、屈光结果、安全性、眼波前像差和非球面性。
CV组中38%的患者最佳矫正视力（BSCVA）得到改善，而PC组为24%（CV/PC组比较，P = 0.38）。CV组诱导的眼性彗差平均为0.17μm，PC组为0.26μm（CV/PC组比较，P = 0.01，CV组更优）。CV组诱导的眼性球差平均为+0.01μm，PC组为+0.07μm（CV/PC组比较，P = 0.05，并CV组更优）。CV组非球面性的变化平均为+0.56，PC组为+0.76（CV/PC组比较，P = 0.05，CV组更优）。治疗后瞳孔偏移未观察到明显变化。
在瞳孔偏移中度至重度的近视眼中，以CV为中心的治疗在诱导眼像差和非球面性方面表现更好，但在明视视力方面两种中心定位方式相同。
