Reproducibility of optical quality parameters measured at objective and subjective best focuses in a doublepass system

• 作者: Ai-Lian Hu Lei Li Li-Ya Qiao Xiao-Gu Cai Xiu-Hua Wan Ye Zhang
• 来源期刊: 国际眼科杂志：英文版
• 学科: 医学
• 关键词: 光质量 双通行证系统 最好集中 重覆性 重制度
• 年，卷（期）: 2015,（5）
• 页码范围: 1043-1050
• 页数: 0页
• 分类号: R73

摘要

AIM: To evaluate intra-session repeatability and reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass system.·METHODS: Thirty Chinese healthy adults(19 to 40 years old) meeting our inclusion criterion were enrolled in the study. After a basic eye examination, two methods of optical quality measurement, based on subjective and objective best focuses were performed using the Optical Quality Analysis System(OQAS) with an artificial pupil diameter of 4.0 mm.·RESULTS: With each method, three consecutive measurements of the following parameters: the modulation transfer function cutoff frequency(MTF cutoff),the Strehl2 D ratio, the OQAS values(OVs) at contrasts of100%, 20%, 9% and the objective scatter index(OSI) were performed by an experienced examiner. The repeatability of each method was evaluated by the repeatability limit(RL) and the coefficient of repeatability(COR).Reproducibility of the two methods was evaluated by intra-class correlation coefficient(ICC) and the 95%limits of agreement(Bland and Altman analysis). Thirty subjects, seven females and twenty three males, of whom 15 right eyes and 15 left eyes were selected randomly for recruitment in the study. The RLs(percentage) for the six parameters measured at objective focus and subjective focus ranged from 8.44% to 15.13%and 10.85% to 16.26%, respectively. The CORs for the two measurement methods ranged from 8.27% to 14.83%and 10.63% to 15.93%, respectively. With regard to reproducibility, the ICCs for the six parameters of OQAS ranged from 0.024 to 0.276. The 95% limits of agreement obtained for the six parameters(in comparison of the two methods) ranged from-0.57 to 42.18(MTF cutoff),-0.01 to 0.23(Strehl2D ratio),-0.02 to 1.40(OV100%),-0.10 to 1.75(OV20%),-0.14 to 1.80(OV9%) and-1.46 to 0.18(OSI).·CONCLUSION: Measurements provided by OQAS with either method showed a good repeatability. However, the results obtained from the two different measurement methods showed a poor reproducibility. These