Han Wei, Kwan William, Wang Jing, Yip Shea Ping, Yap Maurice
Department of Ophthalmology, The First Affiliated Hospital, Medical College, Zhejiang University, Hangzhou, China.
Ophthalmic Physiol Opt. 2007 Jan;27(1):66-75. doi: 10.1111/j.1475-1313.2006.00425.x.
To investigate the influence of eyelid position on wavefront aberrations.
In study 1, the right eyes of 43 non-cyclopleged subjects were evaluated using the Complete Ophthalmic Analysis System (COAS) aberrometer. In study 2, the right eyes of the 23 cyclopleged subjects were evaluated using the Optical Pathway Difference Scan aberrometer. Measurements were made with wide-open and deliberately narrowed palpebral apertures in these subjects. In study 3, the influence of eyelashes on the COAS output was investigated in 20 subjects by placing artificial eyelashes in front of the eye, in close proximity to the natural eyelashes.
For study 1, the total root mean square (RMS) of the third- and fourth-order aberrations with the wide-open lids was significantly different from the narrowed lid position after the correction for multiple comparisons. There was a difference in the Zernike coefficient of the defocus (C4), 90/180 astigmatism (C5), vertical coma (C7) and spherical aberration terms (C12) between the narrowed and wide-open positions. For study 2, changes were observed with the narrowed lid position in the overall RMS of the third and fourth orders, and total coma aberrations, as well as the specific Zernike coefficients of the C5 and C7 terms. However, none of these changes were significant after the multiple comparison correction. The corneal topography also showed remarkable changes in the superior corneal zone. Placing artificial eyelashes in front of the eye significantly affected some Zernike terms and the RMS of the second and fourth orders, and total coma aberrations, for particular pupil sizes.
Deliberate narrowing of the palpebral aperture can influence the wavefront aberrations significantly. The corneal curvature distortion in response to eyelid pressure may account for some of the effect on aberration change. Eyelashes interfering with the light path within the pupil zone distort the output from the COAS, causing significant errors.
研究眼睑位置对波前像差的影响。
在研究1中，使用综合眼科分析系统（COAS）像差仪对43名未散瞳受试者的右眼进行评估。在研究2中，使用光程差扫描像差仪对23名散瞳受试者的右眼进行评估。对这些受试者在睑裂完全张开和故意变窄的情况下进行测量。在研究3中，通过在眼睛前方靠近自然睫毛处放置人工睫毛，对20名受试者研究睫毛对COAS输出的影响。
对于研究1，在进行多重比较校正后，睑裂完全张开时三阶和四阶像差的总均方根（RMS）与睑裂变窄时显著不同。睑裂变窄和完全张开位置之间在离焦（C4）、90/180散光（C5）、垂直彗差（C7）和球差项（C12）的泽尼克系数上存在差异。对于研究2，观察到睑裂变窄时三阶和四阶的总体RMS、总彗差像差以及C5和C7项的特定泽尼克系数有变化。然而，在进行多重比较校正后，这些变化均无统计学意义。角膜地形图也显示上角膜区域有显著变化。在眼睛前方放置人工睫毛对特定瞳孔大小的一些泽尼克项、二阶和四阶的RMS以及总彗差像差有显著影响。
故意缩小睑裂可显著影响波前像差。眼睑压力引起的角膜曲率变形可能是像差变化的部分原因。睫毛干扰瞳孔区内的光路会使COAS的输出失真，导致显著误差。
