University of Houston College of Optometry, Houston, Texas, USA.
Texas Institute for Measurement, Evaluation, and Statistics, Houston, Texas, USA.
Ophthalmic Physiol Opt. 2023 Sep;43(5):1016-1028. doi: 10.1111/opo.13165. Epub 2023 May 19.
Refractions based on the optimisation of single-value wavefront-derived metrics may help determine appropriate corrections for individuals with Down syndrome where clinical techniques fall short. This study compared dioptric differences between refractions obtained using standard clinical techniques and two metric-optimised methods: visual Strehl ratio (VSX) and pupil fraction tessellated (PFSt), and investigated characteristics that may contribute to the differences between refraction types.
Thirty adults with Down syndrome (age = 29 ± 10 years) participated. Three refractive corrections (VSX, PFSt and clinical) were determined and converted to vector notation (M, J , J ) to calculate the dioptric difference between pairings of each type using a mixed model repeated measures approach. Linear correlations and multivariable regression were performed to examine the relationship between dioptric differences and the following participant characteristics: higher order root mean square (RMS) for a 4 mm pupil diameter, spherical equivalent refractive error and Vineland Adaptive Behavior Scales (a measure of developmental ability).
The least squares mean estimates (standard error) of the dioptric differences for each pairing were as follows: VSX versus PFSt = 0.51 D (0.11); VSX versus clinical = 1.19 D (0.11) and PFSt versus clinical = 1.04 D (0.11). There was a statistically significant difference in the dioptric differences between the clinical refraction and each of the metric-optimised refractions (p < 0.001). Increased dioptric differences in refraction were correlated with increased higher order RMS (R = 0.64, p < 0.001 [VSX vs. clinical] and R = 0.47, p < 0.001 [PFSt vs. clinical]) as well as increased myopic spherical equivalent refractive error (R = 0.37, p = 0.004 [VSX vs. clinical] and R = 0.51, p < 0.001 [PFSt vs. clinical]).
The observed differences in refraction demonstrate that a significant portion of the refractive uncertainty is related to increased higher order aberrations and myopic refractive error. Methodology surrounding clinical techniques and metric-optimisation based on wavefront aberrometry may explain the difference in refractive endpoints.
基于单值波前衍生指标优化的验光可能有助于为唐氏综合征患者确定适当的矫正方法，因为临床技术存在局限性。本研究比较了使用标准临床技术和两种基于指标优化的方法（视觉斯特雷尔比（VSX）和瞳孔分数镶嵌（PFSt））获得的验光结果之间的屈光度差异，并探讨了可能导致不同类型验光结果差异的特征。
30 名唐氏综合征成人（年龄=29±10 岁）参与了研究。确定了三种矫正方法（VSX、PFSt 和临床），并将其转换为矢量符号（M、J、J），使用混合模型重复测量方法计算每种类型配对之间的屈光度差异。进行线性相关性和多变量回归分析，以检查屈光度差异与以下参与者特征之间的关系：瞳孔直径为 4mm 时的高阶均方根（RMS）、等效球镜屈光度和 Vineland 适应行为量表（一种发育能力的衡量标准）。
每种配对的屈光度差异最小二乘均值估计值（标准误差）如下：VSX 与 PFSt 差异为 0.51D（0.11）；VSX 与临床差异为 1.19D（0.11），PFSt 与临床差异为 1.04D（0.11）。临床验光与两种基于指标优化的验光之间的屈光度差异存在统计学显著性差异（p<0.001）。屈光度差异增加与高阶 RMS 增加相关（R=0.64，p<0.001 [VSX 与临床]和 R=0.47，p<0.001 [PFSt 与临床]），以及近视等效球镜屈光度增加相关（R=0.37，p=0.004 [VSX 与临床]和 R=0.51，p<0.001 [PFSt 与临床]）。
观察到的验光差异表明，屈光不确定性的很大一部分与高阶像差和近视屈光不正有关。围绕临床技术的方法学以及基于波前像差的指标优化可能解释了验光终点的差异。
