Marsack Jason D, Pesudovs Konrad, Sarver Edwin J, Applegate Raymond A
Visual Optics Institute, College of Optometry, University of Houston, Texas 77204-2020, USA.
J Opt Soc Am A Opt Image Sci Vis. 2006 Apr;23(4):769-76. doi: 10.1364/josaa.23.000769.
This study examines the extent to which a Zernike-based optical correction can restore acuity in keratoconus as a function of disease severity and contrast level. Increasingly complete Zernike corrections in the presence of Zernike-fit error were simulated. Acuity for keratoconic eyes with <60 D maximum corneal power reached 20/13 with a fifth-order Zernike correction under high-contrast conditions and exhibited a loss of 0.1 logMAR (minimum angle of resolution) (from 20/32 to 20/40) for low-contrast conditions. Acuity for keratoconic eyes with >60 D maximum corneal power approached 20/13 with sixth-tenth-order corrections under high-contrast conditions but did not return to similar levels with a tenth-order correction for low-contrast conditions. The results suggest that fit error affects visual performance for more difficult tasks and that restoring high-contrast acuity (20/16 or better) using a fifth-order Zernike correction is not limited by Zernike=fit error for over 88% of keratoconus cases.
本研究探讨基于泽尼克多项式的光学矫正根据圆锥角膜疾病严重程度和对比度水平恢复视力的程度。模拟了在存在泽尼克拟合误差的情况下，越来越完整的泽尼克矫正。最大角膜屈光力<60 D的圆锥角膜眼在高对比度条件下采用五阶泽尼克矫正时视力达到20/13，在低对比度条件下视力损失0.1 logMAR（最小分辨角）（从20/32降至20/40）。最大角膜屈光力>60 D的圆锥角膜眼在高对比度条件下采用六至十阶矫正时视力接近20/13，但在低对比度条件下采用十阶矫正时未恢复到相似水平。结果表明，拟合误差会影响更困难任务的视觉表现，并且对于超过88%的圆锥角膜病例，使用五阶泽尼克矫正恢复高对比度视力（20/16或更好）不受泽尼克拟合误差的限制。
