Department of Vision Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Invest Ophthalmol Vis Sci. 2010 May;51(5):2764-9. doi: 10.1167/iovs.09-4717. Epub 2009 Dec 10.
A sustained pupilloconstriction is often observed after the cessation of a bright visual stimulus. This post-illumination pupil response (PIPR) is produced by the intrinsically photosensitive retinal ganglion cells (ipRGCs). The present study was designed to examine the characteristics of the PIPR in a normal population without ocular disease.
Thirty-seven subjects (mean age, 48.6 years) were tested by presenting a 60 degrees, 10-second light stimulus (13 log quanta/cm(2)/s retinal irradiance) and recording pupillary responses for 50 seconds after light cessation. The light stimuli (470 [blue] and 623 [red] nm) were presented by an optical system to one eye after dilation, while the consensual pupil response of the fellow, undilated eye was recorded by infrared pupillometry.
A positive PIPR was seen in all subjects tested. The population average of the PIPR for 470-nm light was 1.5 mm (SEM 0.10, P < 0.05) and the net PIPR (blue PIPR minus red PIPR) was 1.4 mm (SEM 0.09, P < 0.0001). The net PIPR correlated positively with baseline pupil diameter (P < 0.05), but not significantly with age, race, or sex (P > 0.05) in the test population.
All normal subjects displayed a significant PIPR for a 10-second, 470-nm light stimulus, but not a 623-nm stimulus, which is consistent with the proposed melanopsin-mediated response. In most normal individuals, the amplitude of the PIPR was substantial. This test has the potential to be used as a tool in evaluating subjects with inner retinal dysfunction or melanopsin-related disorders.
在停止明亮视觉刺激后，常观察到持续的瞳孔收缩。这种光后瞳孔反应（PIPR）是由内在感光视网膜神经节细胞（ipRGCs）产生的。本研究旨在检查无眼部疾病的正常人群中 PIPR 的特征。
对 37 名受试者（平均年龄 48.6 岁）进行测试，通过呈现 60 度、10 秒的光刺激（视网膜辐照度为 13 对数量子/cm(2)/s），并在光停止后记录 50 秒的瞳孔反应。光刺激（470[蓝色]和 623[红色]nm）通过光学系统呈现给一只散瞳后的眼睛，而未散瞳的对侧眼睛的协同瞳孔反应则通过红外瞳孔测量法记录。
所有测试的受试者均出现阳性 PIPR。470nm 光的人群平均 PIPR 为 1.5mm（SEM 0.10，P<0.05），净 PIPR（蓝 PIPR 减去红 PIPR）为 1.4mm（SEM 0.09，P<0.0001）。净 PIPR 与基础瞳孔直径呈正相关（P<0.05），但与受试人群的年龄、种族或性别无显著相关性（P>0.05）。
所有正常受试者对 10 秒 470nm 光刺激均显示出显著的 PIPR，但对 623nm 刺激无反应，这与拟议的黑视素介导反应一致。在大多数正常个体中，PIPR 的幅度相当大。该测试有可能成为评估内视网膜功能障碍或黑视素相关疾病患者的工具。
