Clinical Ophthalmology (Dec 2011)
Correlation between contrast sensitivity and higher-order aberration based on pupil diameter after cataract surgery
Abstract
Takefumi Yamaguchi1,2, Kazuno Negishi1, Kazuhiko Ohnuma3, Kazuo Tsubota11Department of Ophthalmology, Keio University School of Medicine, Tokyo; 2Department of Ophthalmology, Ichikawa General Hospital, Tokyo Dental College, Chiba; 3Department of Medical System Engineering, Faculty of Engineering, Chiba University, Chiba, JapanBackground: The purpose of this study was to evaluate the correlation between contrast sensitivity and calculated higher-order aberrations based on individual natural pupil diameter after cataract surgery.Methods: This prospective study included 120 eyes from 92 patients who were randomized to receive one of four lenses, including three aspheric lenses (Acrysof SN60WF, Tecnis ZA9000, and Hoya Py60AD) and one spherical lens (Acrysof SN60AT). Contrast sensitivity, higher-order aberrations of the whole eye, and pupil diameter under photopic and mesopic conditions were measured 1 month postoperatively. Higher-order aberrations were decomposed into Zernike coefficients, calculated according to individual pupil diameter. The correlation between higher-order aberrations and contrast sensitivity was evaluated.Results: There were no significant differences in contrast sensitivity function between the four types of lenses under photopic conditions. However, the contrast sensitivity function and area under log contrast sensitivity function in the aspheric lenses were significantly better than in the spherical lens under mesopic conditions. Under mesopic conditions, spherical aberration in eyes with aspheric lenses was significantly lower than in eyes with spherical lenses (P < 0.05). Under photopic conditions, coma aberration had a significant negative correlation with contrast sensitivity at 12 cycles/degree. Under mesopic conditions, spherical aberration had a significant negative correlation with contrast sensitivity at 3, 6, and 12 cycles/degree with glare, and with contrast sensitivity at 6 and 18 cycles/degree without glare.Conclusion: In terms of influence on visual function, coma aberration may be more significant under photopic conditions and spherical aberration under mesopic conditions.Keywords: mesopic conditions, spherical aberration, wavefront, photopic and mesopic conditions