College of Medicine, The Ohio State University, Columbus, OH, USA.
Graefes Arch Clin Exp Ophthalmol. 2011 Sep;249(9):1345-52. doi: 10.1007/s00417-011-1706-9. Epub 2011 May 21.
To examine and quantify any change in the dark adaptation (DA) function of normal subjects due to learning effect on test-retest.
Sixteen normal subjects (12 women, four men) whose ages ranged between 24 and 52 years (mean 34.6 ± 6.7 years) were studied. The interval period between test and retest ranged between 0.92 and 2.37 months (mean 1.38 ± 0.40 months). DA was measured with a Goldmann-Weekers (GW) dark adaptometer, and subjects were pre-adapted using a light intensity of 2,700 cd/m(2) Ganzfeld background for 5 minutes. Exponential non-linear regression analysis was used to determine seven parameters of DA function. These were time of cone-rod break, cone and rod final thresholds, and magnitude of change and time constant of the cone and rod limbs.
The mean cone-rod break time with 95% confidence intervals (CI) was 0.098 (CI: -0.527, 0.330) minutes faster on retest (p = 0.630)). Fourteen of the 16 subjects demonstrated an increase or 'worsening' of their final cone and rod thresholds on the second visit. The mean final threshold differences on retest for the cone limb was 0.105 (CI: 0.032, 0.179) log cd/m(2) (p = 0.008) and 0.093 (CI: -0.039, 0.225,) log cd/m(2) (p = 0.155) for the rod limb. The magnitude of change for the cone limb was 0.016 (CI: -0.122, 0.155) log cd/m(2) (p = 0.805) and -0.196 (CI: -0.435, 0.827) log cd/m2 (p = 0.518) for the rod limb, while the time constant on retest for the cone limb was -0.021 (CI: -0.128, 0.169) minutes, (p = 0.770) and 0.276 (CI: -0.424, 0.976) minutes (p = 0.410) for the rod limb.
None of the DA parameters that were examined demonstrated a learning effect of clinical significance between test and retest. None of the changes in mean from test to retest for the seven parameters were found to be statistically significant, and the changes were clinically negligible. Therefore, any change among patients that may occur in dark adaptation between a visit interval may be considered real, and not due to the effect of learning.
通过测试-再测试，研究并量化正常受试者的暗适应（DA）功能因学习效应而发生的任何变化。
研究了 16 名年龄在 24 至 52 岁之间（平均 34.6±6.7 岁）的正常受试者（12 名女性，4 名男性）。测试和再测试之间的间隔时间为 0.92 至 2.37 个月（平均 1.38±0.40 个月）。使用 Goldmann-Weekers（GW）暗适应计测量 DA，受试者在 2700 cd/m2 的 Ganzfeld 背景光强度下预先适应 5 分钟。采用指数非线性回归分析来确定 DA 功能的七个参数。这些参数包括视锥-视杆转换时间、视锥和视杆最终阈值以及视锥和视杆支腿的变化幅度和时间常数。
16 名受试者中有 14 名在第二次就诊时表现出最终视锥和视杆阈值的增加或“恶化”。再测试时，视锥支腿的最终阈值差异平均为 0.105（CI：0.032，0.179）log cd/m2（p=0.008），视杆支腿的最终阈值差异平均为 0.093（CI：-0.039，0.225）log cd/m2（p=0.155）。视锥支腿的变化幅度平均为 0.016（CI：-0.122，0.155）log cd/m2（p=0.805），视杆支腿的变化幅度平均为-0.196（CI：-0.435，0.827）log cd/m2（p=0.518）。再测试时，视锥支腿的时间常数为-0.021（CI：-0.128，0.169）分钟（p=0.770），视杆支腿的时间常数为 0.276（CI：-0.424，0.976）分钟（p=0.410）。
在测试和再测试之间，没有一个 DA 参数显示出具有临床意义的学习效应。七个参数中，从测试到再测试的平均值变化均无统计学意义，变化程度在临床可忽略范围内。因此，在就诊间隔期间，患者的暗适应中出现的任何变化都可能是真实的，而不是由于学习效果的影响。
