超高度近视眼角膜高阶像差的特点

Higher-order aberrations in severe high myopia

目的分析超高度近视眼角膜高阶像差的分布特点以及各高阶像差与球镜及柱镜的关系。方法横断面研究。选取2015年7月至2017年3月在广东省人民医院眼科拟行可植入眼内接触镜手术而行术前检查的超高度近视眼患者,球镜屈光度在-10. 0 D以上的患者纳入研究。应用Pentacam眼前节分析系统采集角膜像差。角膜波前像差分析均为6 mm瞳孔直径。结果共有23例(40只眼)纳入研究,平均年龄(25. 78±5. 90)岁,平均球镜(-13. 47±2. 58) D,平均柱镜(-1. 08±1. 11) D。在6 mm瞳孔直径下,角膜高阶像差以3阶和4阶为主,高阶像差均方根(RMS)值呈递减趋势,阶数越高,像差越小。总高阶像差RMS值为(1. 418±1. 001)μm,4阶(Z_4) RMS值最大(0. 789±0. 345)μm,3阶(Z_3)次之(0. 753±0. 481)μm。总像差RMS值、各高阶像差RMS值、慧差、球差与球镜度数无相关性;总像差RMS值与柱镜度数(r=-0. 563,P=0. 000)、球差与柱镜度数(r=0. 330,P=0. 037)有相关性。结论超高度近视眼角膜高阶像差个体差异较大,4阶RMS值最大,3阶次之,各高阶像差RMS值随阶数增加大致呈递减趋势。总高阶像差RMS值与球镜度数无相关性,总像差RMS值与柱镜度数、球差与柱镜度数有相关性。

Objective To describe the characteristics of higher order aberrations（HOA） in young patients with severe myopia. Methods Cross-sectional study. Patients with severe myopia who want to do Implantable collamer lens were recruited in ophthalmology of Gongdong Gerneral Hospital.The spheres over -10.0 diopters（D） were enrolled, Corneal aberrations were obtained with the Pentacam system.Wavefront aberrations were analyzed for 6 mm pupil zone. Results Mean patient age was （25.78±5.90） years, the mean refractive error was sphere （-13.47±2.58）D and cylinder （-1.08±1.11）D. The mean of the total higher order root mean square （RMS） （third to sixth order）was （1.418±1.001）μm. Fourth-order RMS was the largest（0.789±0.345）μm,followed by third-order RMS （0.753±0.481）μm. For individual higher order Zernike coefficients, spherical aberration （Z 4 0） predominated with a mean of （0.599±0.336）μm. No correlation was found between RMS HOA and myopia. statistically significant relationships were found between RMS and astigmatis （ r =-0.563, P =0.000）, spherical aberration （Z 4 0） and astigmatis （ r =0.330, P =0.037）. Conclusions Higher order aberrations varied among individuals in severe myopia. Fourth-order RMS was the predominant higher order aberration. RMS HOA and myopia was no correlation. Statistically significant relationships were found between RMS and astigmatis, spherical aberration （Z 4 0） and astigmatis.