Hayashi Ken, Kawahara Sumie, Manabe Shin-ichi, Hirata Akira
Invest Ophthalmol Vis Sci. 2015 Dec;56(13):7988-98. doi: 10.1167/iovs.15-18058.
To investigate the changes in irregular and regular corneal astigmatism with age in eyes that underwent cataract surgery (surgery group) and in eyes that did not undergo surgery (nonsurgery group).
We enrolled 120 eyes in each of four age groups in the surgery and nonsurgery groups: (1) 50 to 59 years of age, (2) 60 to 69 years of age, (3) 70 to 79 years of age, and (4) older than or equal to 80 years of age. Eyes in the surgery group underwent videokeratographic examination, at least 6 months postoperatively. Irregular astigmatism components, corneal asymmetry, and higher-order irregularity components were determined using Fourier analysis. The regular astigmatism vector was decomposed into vertical/horizontal (J0) and oblique (J45) components using power vector analysis.
Both the mean corneal asymmetry and higher-order irregularity components significantly increased with increasing age in both groups (P < 0.0001). Higher-order irregularity was greater in the surgery group than in the nonsurgery group in all age groups (P ≤ 0.0128). The asymmetry did not differ significantly between groups. Asymmetry and higher-order irregularity were positively correlated with actual age in both the surgery and nonsurgery groups (P < 0.0001). The J0 decreased significantly with age in both groups (P < 0.0001), whereas the J45 did not vary significantly with age.
In patients from 50 to 80 years of age who underwent cataract surgery, irregular corneal astigmatism, both the asymmetry and higher-order irregularity components, increased significantly with increasing age, whereas regular astigmatism induces an against-the-rule shift. The higher-order irregularity component persistently increased postoperatively, whereas the asymmetry component did not change significantly.
研究白内障手术眼（手术组）和未手术眼（非手术组）中不规则和规则角膜散光随年龄的变化情况。
手术组和非手术组各纳入四个年龄组的120只眼：（1）50至59岁，（2）60至69岁，（3）70至79岁，（4）80岁及以上。手术组的眼睛在术后至少6个月接受了角膜地形图检查。使用傅里叶分析确定不规则散光成分、角膜不对称性和高阶不规则成分。使用功率矢量分析将规则散光矢量分解为垂直/水平（J0）和斜向（J45）成分。
两组中，平均角膜不对称性和高阶不规则成分均随年龄增长而显著增加（P < 0.0001）。在所有年龄组中，手术组的高阶不规则性均高于非手术组（P≤0.0128）。两组间不对称性无显著差异。手术组和非手术组中，不对称性和高阶不规则性均与实际年龄呈正相关（P < 0.0001）。两组中J0均随年龄显著降低（P < 0.0001），而J45随年龄无显著变化。
在50至80岁接受白内障手术的患者中，不规则角膜散光，包括不对称性和高阶不规则成分，均随年龄增长而显著增加，而规则散光则导致逆规性偏移。高阶不规则成分术后持续增加，而不对称成分无显著变化。
