Xu Zequan, Hua Yanjun, Qiu Wei, Li Guoqiang, Wu Qiang
Department of Ophthalmology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, NO. 600, Yishan Road, Xuhui District, Shanghai, 200233, China.
Visual and Biomedical Optics Lab, Department of Ophthalmology and Visual Science, The Ohio State University, 1330 Kinnear Road, Columbus, OH, USA.
BMC Ophthalmol. 2018 Jan 27;18(1):18. doi: 10.1186/s12886-018-0683-8.
To assess the precision and agreement of measurements of higher order aberrations (HOAs) obtained with a ray tracing aberrometer (iTrace) and a Hartmann-Shack aberrometer (Topcon KR-1 W).
Prospective evaluation of the diagnostic test. Data from the right eyes of 92 normal subjects obtained using the two devices were included in this study. Two observers performed 3 consecutive scans to determine the intraobserver repeatability and interobserver reproducibility. About one week later, one observer performed an additional 3 consecutive scans to obtain the intersession reproducibility. The within-subject standard deviation (Sw), test-retest repeatability (TRT) and intraclass correlation coefficient (ICC) were used to assess the precision, while Bland-Altman plots were performed to assess the agreement.
For intraobserver repeatability of the ocular, corneal and internal HOAs, Topcon KR-1 W showed a 2.77Sw of 0.079 μm or less and ICCs of 0.761 or more; and iTrace showed a 2.77Sw of 0.105 μm or less and ICCs of 0.805 or more. The ICCs of the internal HOAs of interobserver reproducibility were less than 0.75 except for spherical aberration (SA) (0.862), and interobserver reproducibility of the counterpart showed similar but lower results. For the ocular, corneal and internal HOA measurements, statistically significant differences existed between the Topcon KR-1 W and iTrace (all P < 0.05). No significant differences were observed in the ocular SA and internal coma.
The ray tracing and Hartmann-Shack method aberrometers provided excellent repeatability but less reliable reproducibility in the measurement of HOAs (except for SA). The two aberrometers should not be interchangeable in clinical application because of the significant differences in HOA measurements between them.
评估使用光线追踪像差仪（iTrace）和哈特曼-夏克像差仪（Topcon KR-1W）获得的高阶像差（HOA）测量的精度和一致性。
对诊断测试进行前瞻性评估。本研究纳入了使用这两种设备获得的92名正常受试者右眼的数据。两名观察者进行了3次连续扫描，以确定观察者内重复性和观察者间再现性。大约一周后，一名观察者又进行了3次连续扫描，以获得不同测量时段间的再现性。受试者内标准差（Sw）、重测重复性（TRT）和组内相关系数（ICC）用于评估精度，同时采用Bland-Altman图评估一致性。
对于眼内、角膜和内部HOA的观察者内重复性，Topcon KR-1W的2.77Sw为0.079μm或更低，ICC为0.761或更高；iTrace的2.77Sw为0.105μm或更低，ICC为0.805或更高。除球差（SA）（0.862）外，观察者间再现性的内部HOA的ICC小于0.75，对应部分的观察者间再现性显示出相似但更低的结果。对于眼内、角膜和内部HOA测量，Topcon KR-1W和iTrace之间存在统计学显著差异（所有P < 0.05）。在眼内SA和内部彗差方面未观察到显著差异。
光线追踪和哈特曼-夏克方法像差仪在HOA测量中（SA除外）提供了出色的重复性，但再现性不太可靠。由于两种像差仪在HOA测量上存在显著差异，它们在临床应用中不应互换使用。
