Vision Science Research Program, Toronto Western Hospital, Toronto, Canada.
Invest Ophthalmol Vis Sci. 2011 Mar 30;52(3):1887-93. doi: 10.1167/iovs.10-6059.
The authors examined the fixation stability of patients with age-related macular degeneration (AMD) and large interocular acuity differences, testing them in monocular and binocular viewing conditions. The relationship between fixation stability and visual performance during monocular and binocular viewing was also studied.
Twenty patients with AMD participated. Their monocular and binocular distance acuities were measured with the ETDRS charts. Fixation stability of the better and worse eye were recorded monocularly with the MP-1 microperimeter (Nidek Technologies Srl., Vigonza, PD, Italy) and binocularly with an EyeLink eye tracker (SR Research Ltd., Mississauga, Ontario, Canada). Additional recordings of monocular fixations were obtained with the EyeLink in viewing conditions when one eye viewed the target while the fellow eye was covered by an infrared filter so it could not see the target.
Fixation stability of the better eye did not change across viewing conditions. Fixation stability of the worse eye was 84% to 100% better in the binocular condition than in monocular conditions. Fixation stability of the worse eye was significantly larger (P < 0.05) than that of the better eye when recorded monocularly with the MP-1 microperimeter. This difference was dramatically reduced in the binocular condition but remained marginally significant (95% confidence interval, -0.351 to -0.006). For the better eye, there was a moderate relationship between fixation stability and visual acuity, both monocular and binocular, in all conditions in which this eye viewed the target.
Fixational ocular motor control and visual acuity are driven by the better-seeing eye when patients with AMD and large interocular acuity differences perform the tasks binocularly.
作者检查了年龄相关性黄斑变性（AMD）和较大眼间视力差异患者的固视稳定性，分别在单眼和双眼观察条件下对其进行测试。还研究了单眼和双眼观察期间固视稳定性与视觉表现之间的关系。
20 名 AMD 患者参与了这项研究。他们的单眼和双眼远视力通过 ETDRS 图表进行测量。使用 MP-1 微视野计（日本尼德克公司，维戈扎，PD）对较好眼和较差眼的固视稳定性进行单眼记录，使用 EyeLink 眼动追踪器（加拿大安大略省密西沙加市 SR Research Ltd.）进行双眼记录。在一只眼睛注视目标而另一只眼睛被红外滤光片覆盖而无法看到目标的情况下，使用 EyeLink 在单眼观察条件下获得额外的单眼注视记录。
较好眼的固视稳定性在不同观察条件下没有变化。在双眼条件下，较差眼的固视稳定性比单眼条件下提高了 84%至 100%。使用 MP-1 微视野计单眼记录时，较差眼的固视稳定性明显大于（P<0.05）较好眼。在双眼条件下，这种差异显著减小，但仍具有边缘显著性（95%置信区间，-0.351 至-0.006）。对于较好眼，在该眼注视目标的所有情况下，单眼和双眼的固视稳定性与视力均呈中度相关。
当 AMD 患者和较大眼间视力差异患者进行双眼任务时，固视眼动控制和视力由视力较好的眼睛驱动。
