Properties of the Statpac Visual Field Index
Properties of the Statpac Visual Field Index
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DOI：
10.1167/iovs.10-6905
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发表时间：
2011-06-01
影响因子：
4.4
通讯作者：
Chauhan, Balwantray C.
中科院分区：
文献类型：
--
作者：
Artes, Paul H.;O'Leary, Neil;Chauhan, Balwantray C.
目的。比较青光眼患者的视野指数（VFI）与平均偏差（MD）的特点。MD和VFI的计算数据来自一项正在进行的纵向研究，在该研究中，青光眼患者（N = 109,204只眼睛）使用静态自动视距仪观察了9.8年（中位数，21次）。在每只眼睛的一次测试中比较MD和VFI，并选择30个测试的子集将VFI与8位判断剩余视野百分比的专家的判断进行比较。在一段时间内获得的一系列测试中，比较了两个指标之间的变化率、统计显著性、非线性证据和可变性。在单次试验中，MD与VFI密切相关（r = 0.88, P < 0.001）。两个指标之间呈线性关系，但在MDs优于-5.0 dB的视野中，129只眼睛中有29只（22%）出现天花板效应（VFI = 100%）。基于这一关系，对于md为-5、-10和-15 dB的视场，预测vfi分别为91%、76%和60%。在30只眼睛中，有16只（53%）的VFI建议的剩余视野百分比超过了专家主观判断的范围。随着时间的推移，在一系列测试中，这两个指标的变化率密切相关（r = 0.79, P < 0.001），并且随着时间的推移，在相同数量的眼睛中出现了统计学上显著的降低（P < 0.05） （MD 92 [45%], VFI 87[43%]）。在有统计学意义（P < 0.05）的MD或VFI阴性趋势的105只眼中，74只（70%）眼同时有MD或VFI阴性趋势（kappa = 0.69）。MD和VFI的变异性随着损伤的增加而增加，没有证据表明VFI随时间的变化比MD更线性。VFI提供了一个简单易懂的视野损害指标，但它对剩余视野的估计比专家们更乐观。随着时间的推移，这两个指数的变化率密切相关，但VFI对模式偏差概率图的依赖造成了天花板效应，这可能降低了它对早期损伤眼睛变化的敏感性。在这组患者中，没有证据表明VFI优于或低于MD作为视野损害的综合测量。（Invest Ophthalmol Vis Sci. 2011;52:4030-4038） DOI:10.1167/iovs.10-6905
PURPOSE. To compare the properties of the visual field index (VFI) to those of mean deviation (MD) in patients with glaucoma.METHODS. MD and VFI were calculated in data obtained from an ongoing longitudinal study in which patients with glaucoma (N = 109, 204 eyes) were observed for 9.8 years (median, 21 tests) with static automated perimetry. MD and VFI were compared in one test of each eye, and a subset of 30 tests were selected to compare the VFI with the judgments of eight experts who judged the percentage of the remaining visual field. In series of tests obtained over time, rates of change, statistical significance, evidence of nonlinearity, and variability were compared between both indices.RESULTS. In single tests, MD and VFI were closely related (r = 0.88, P < 0.001). The relationship between both indices appeared linear, except in visual fields with MDs better than -5.0 dB where 29 (22%) of 129 eyes exhibited a ceiling effect (VFI = 100%). Based on this relationship, the predicted VFIs for visual fields with MDs of -5, -10, and -15 dB were 91%, 76%, and 60%, respectively. The percentage of remaining visual field suggested by the VFI exceeded the range of the experts' subjective judgments in 16 (53%) of 30 eyes. In series of tests obtained over time, rates of change with the two indices were closely related (r = 0.79, P < 0.001), and statistically significant reductions over time (P < 0.05) occurred in a similar number of eyes (92 [45%] with MD, and 87 [43%] with VFI). Of the 105 eyes with statistically significant (P < 0.05) negative trend in either MD or VFI, 74 (70%) showed such trends with both indices (kappa = 0.69). The variability of MD and VFI increased with damage, and there was no evidence that change over time was more linear with VFI than with MD.CONCLUSIONS. The VFI provides a simple and understandable metric of visual field damage, but its estimates of remaining visual field were more optimistic than those of the experts. Rates of change over time with both indices were closely related, but the reliance of the VFI on pattern deviation probability maps caused a ceiling effect that may have reduced its sensitivity to change in eyes with early damage. In this group of patients there was no evidence to suggest that the VFI is either superior or inferior to the MD as a summary measure of visual field damage. (Invest Ophthalmol Vis Sci. 2011;52:4030-4038) DOI:10.1167/iovs.10-6905