Centre for Optometry and Vision Science Research, Ulster University, Northern Ireland, United Kingdom.
University of Houston College of Optometry, Houston, Texas.
Optom Vis Sci. 2020 Mar;97(3):198-206. doi: 10.1097/OPX.0000000000001486.
Pupillometry protocols evaluating rod/cone- and melanopsin-driven responses often use mydriatics to ensure maximal stimulus exposure; however, retinal effects of mydriatics are not fully understood. We demonstrate that dilation with either atropine or phenylephrine results in similar enhancements of rod/cone- and melanopsin-driven pupil responses.
The purposes of this study were to compare the effects of atropine, a muscarinic antagonist, and phenylephrine, an adrenergic agonist, on consensual pupil responses and to assess the repeatability of pupil metrics without mydriasis.
Right eye pupil responses of 20 adults aged 21 to 42 years were recorded before and 45 minutes after instillation of 0.5% atropine or 2.5% phenylephrine in the left eye. Stimuli were presented to the left eye and included six alternating 1-second 651-nm "red" and 456-nm "blue" flashes. Metrics included baseline pupil diameter, maximal constriction, 6- and 30-second post-illumination pupil responses, and early (0 to 10 seconds) and late (10 to 30 seconds) areas under the curve.
Dilation of the stimulated eye with either mydriatic significantly increased the 6-second post-illumination pupil response and early and late areas under the curve for blue stimuli, and early area under the curve for red stimuli (P < .05 for all). Melanopsin-driven post-illumination pupil responses, achieved with either phenylephrine or atropine, did not significantly differ from each other (P > .05 for all). Without mydriasis, intersession intraclass correlation coefficients for pupil metrics were 0.63 and 0.50 (6- and 30-second post-illumination pupil responses, respectively) and 0.78 and 0.44 (early and late areas under the curve, respectively) for blue stimuli, with no significant difference between sessions (P > .05 for all).
Dilation with phenylephrine or atropine resulted in similar enhancements of the rod/cone- and melanopsin-driven pupil responses, despite differing mechanisms. Early pupil metrics without mydriasis demonstrated moderate to good intersession repeatability.
评估视杆/视锥细胞和黑素视蛋白驱动反应的瞳孔测量协议通常使用散瞳剂以确保最大的刺激暴露；然而，散瞳剂对视网膜的影响尚未完全了解。我们证明，用阿托品或苯肾上腺素散瞳都会导致视杆/视锥细胞和黑素视蛋白驱动的瞳孔反应相似的增强。
本研究的目的是比较阿托品（一种毒蕈碱拮抗剂）和苯肾上腺素（一种肾上腺素能激动剂）对瞳孔的影响，并评估无散瞳时瞳孔测量的可重复性。
20 名年龄在 21 至 42 岁的成年人右眼的瞳孔反应在左眼滴入 0.5%阿托品或 2.5%苯肾上腺素前后 45 分钟进行记录。刺激物被呈现给左眼，包括六个交替的 1 秒 651nm“红色”和 456nm“蓝色”闪光。指标包括基础瞳孔直径、最大收缩、6 秒和 30 秒光照后瞳孔反应以及早期（0 到 10 秒）和晚期（10 到 30 秒）曲线下面积。
用任何一种散瞳剂散瞳都会显著增加受刺激眼的 6 秒光照后瞳孔反应以及蓝色刺激的早期和晚期曲线下面积，并增加红色刺激的早期曲线下面积（所有 P 值均<.05）。用苯肾上腺素或阿托品获得的视蛋白驱动的光照后瞳孔反应彼此之间没有显著差异（所有 P 值均>.05）。无需散瞳，瞳孔指标的两次试验间组内相关系数为 0.63 和 0.50（分别为 6 秒和 30 秒光照后瞳孔反应）和 0.78 和 0.44（分别为早期和晚期曲线下面积），两次试验间无显著差异（所有 P 值均>.05）。
尽管作用机制不同，但用苯肾上腺素或阿托品散瞳都会导致视杆/视锥细胞和黑素视蛋白驱动的瞳孔反应相似的增强。无需散瞳的早期瞳孔指标具有中等至良好的两次试验间可重复性。
