Smolek M K, Oshika T, Klyce S D, Maeda N, Haight D H, McDonald M B
LSU Eye Center, New Orleans, Louisiana 70112, USA.
J Cataract Refract Surg. 1998 Aug;24(8):1079-86. doi: 10.1016/s0886-3350(98)80101-6.
To correlate new quantitative topographic indexes of corneal irregular astigmatism to best spectacle-corrected visual acuity (BSCVA) following excimer laser photorefractive keratectomy (PRK).
Department of Ophthalmology, LSU Eye Center, and Refractive Surgery Center of the South, Ear, Nose & Throat Hospital, New Orleans, Louisiana; Manhattan Eye, Ear and Throat Hospital, New York, New York, USA.
Videokeratography data (TMS-1) were obtained preoperatively and 1, 3, 6, 12, 18, and 24 months postoperatively from 100 eyes having PRK for low to mild myopia. Algorithms measured fine local irregularity with the surface regularity index (SRIp), varifocality with the coefficient of variation of corneal power (CVPp), and central islands with the elevation/depression magnitude (EDM).
The SRIp and CVPp increased after surgery and remained significantly higher than the preoperative levels throughout the 24 month follow-up (P < .05). The increase in EDM was significant from 1 to 6 months (P < .05) but not thereafter. Multiple regression analysis revealed that variables having a statistically significant relationship with postoperative BSCVA were CVPp and EDM at 1 month, CVPp at 3 months, and CVPp, haze, and age at 6 months. No statistically significant correlation between any measures of irregular astigmatism and BSCVA was found after 1 year of follow-up.
The quantitative measures used in this study are sensitive methods by which irregular astigmatism after keratorefractive procedures can be classified, evaluated, and compared.
将角膜不规则散光的新定量地形图指标与准分子激光屈光性角膜切削术（PRK）后最佳眼镜矫正视力（BSCVA）进行关联分析。
美国路易斯安那州新奥尔良市路易斯安那州立大学眼科中心、南方耳鼻喉医院屈光手术中心；美国纽约市曼哈顿眼耳鼻喉医院。
对100例行PRK治疗低度至中度近视的眼睛，在术前及术后1、3、6、12、18和24个月获取角膜地形图数据（TMS-1）。通过表面规则性指数（SRIp）测量细微局部不规则性，通过角膜屈光力变异系数（CVPp）测量变焦能力，通过高度/凹陷幅度（EDM）测量中央岛。
术后SRIp和CVPp升高，在整个24个月随访期间均显著高于术前水平（P <.05）。EDM从1个月至6个月显著增加（P <.05），此后无明显变化。多元回归分析显示，与术后BSCVA有统计学显著关系的变量为1个月时的CVPp和EDM、3个月时的CVPp以及6个月时的CVPp、 haze和年龄。随访1年后，未发现任何不规则散光测量指标与BSCVA之间存在统计学显著相关性。
本研究中使用的定量测量方法是敏感的方法，可用于对角膜屈光手术后的不规则散光进行分类、评估和比较。
