PDF(Pubmed)
Abstract：
BACKGROUND: There have recently been several clinical studies suggesting that brief periods of exposure to red light (repeated low-level red light, \'RLRL\') may produce a dramatic anti-myopia effect, calling for further investigations into its therapeutic parameters. Unfortunately, many experimental species used in refractive studies develop myopia in response to this wavelength. Tree shrews are the only animal model other than rhesus monkeys that consistently exhibit hyperopic responses to ambient red light. Here, tree shrews were used to study the influence of the spectral purity, duty cycle and intensity of red light on its anti-myopic effect.
METHODS: Juvenile tree shrews (Tupaia belangeri) were raised from 24 to 35 days after eye opening under ambient lighting that was: standard white colony fluorescent light; pure narrow band red light of either 600, 50-100 or 5 lux; red light that was diluted with 10% white light (by lux) or 50% white and 2 s of pure red light that alternated with 2 s of pure white light (50% duty cycle). Refractive measures were taken with a NIDEK ARK-700 autorefractor and axial dimensions with a LenStar LS-900 Axial Biometer.
RESULTS: The pro-hyperopia effect of ambient red light was greatly reduced by even small amounts of concurrent white light \'contamination\', but remained robust if 2-s periods of pure white light alternated with 2 s of red. Finally, the hyperopic effect of red light was maintained at reduced luminance levels in the 50-100 lux range and only failed at 5 lux.
CONCLUSIONS: These results have implications for understanding the mechanisms by which ambient red light affects refractive development, and possibly also for clinical therapies using RLRL. Nevertheless, it remains to be determined if the mechanism of the current clinical RLRL therapy is the same as that operating on tree shrews in ambient red light.
METHODS: Juvenile tree shrews (Tupaia belangeri) were raised from 24 to 35 days after eye opening under ambient lighting that was: standard white colony fluorescent light; pure narrow band red light of either 600, 50-100 or 5 lux; red light that was diluted with 10% white light (by lux) or 50% white and 2 s of pure red light that alternated with 2 s of pure white light (50% duty cycle). Refractive measures were taken with a NIDEK ARK-700 autorefractor and axial dimensions with a LenStar LS-900 Axial Biometer.
RESULTS: The pro-hyperopia effect of ambient red light was greatly reduced by even small amounts of concurrent white light \'contamination\', but remained robust if 2-s periods of pure white light alternated with 2 s of red. Finally, the hyperopic effect of red light was maintained at reduced luminance levels in the 50-100 lux range and only failed at 5 lux.
CONCLUSIONS: These results have implications for understanding the mechanisms by which ambient red light affects refractive development, and possibly also for clinical therapies using RLRL. Nevertheless, it remains to be determined if the mechanism of the current clinical RLRL therapy is the same as that operating on tree shrews in ambient red light.
摘要：
背景：最近有几项临床研究表明，短时间暴露于红光（反复的低水平红光，\'RLRL\')可能会产生戏剧性的抗近视效果，要求对其治疗参数进行进一步调查。不幸的是,屈光研究中使用的许多实验物种都会对这种波长产生近视。树sh是除恒河猴以外唯一对环境红光表现出远视反应的动物模型。这里,使用树sh来研究光谱纯度的影响，占空比和红光强度对其抗近视作用的影响。
方法：睁眼后24至35天，在环境照明下饲养幼树sh（Tupaiabelangeri），该照明为：标准白色菌落荧光灯；600、50-100或5勒克斯的纯窄带红光；用10％白光（按勒克斯）或50％白光稀释的红光和2s纯红光，与50％白光交替循环（交替）。使用NIDEKARK-700自动折光仪进行屈光测量，并使用LenStarLS-900轴向测距仪进行轴向尺寸测量。
结果：即使是少量的同时发生的白光“污染”，也大大降低了环境红光对远视的影响，但如果2秒的纯白色光与2秒的红色交替，则保持稳健。最后,红光的远视效应在50-100勒克斯范围内的亮度水平降低时保持不变，仅在5勒克斯时失效。
结论：这些结果对理解环境红光影响屈光发育的机制具有重要意义。也可能用于使用RLRL的临床治疗。然而，目前的临床RLRL治疗的机制是否与在环境红光下对树sh进行治疗的机制相同尚待确定.
方法：睁眼后24至35天，在环境照明下饲养幼树sh（Tupaiabelangeri），该照明为：标准白色菌落荧光灯；600、50-100或5勒克斯的纯窄带红光；用10％白光（按勒克斯）或50％白光稀释的红光和2s纯红光，与50％白光交替循环（交替）。使用NIDEKARK-700自动折光仪进行屈光测量，并使用LenStarLS-900轴向测距仪进行轴向尺寸测量。
结果：即使是少量的同时发生的白光“污染”，也大大降低了环境红光对远视的影响，但如果2秒的纯白色光与2秒的红色交替，则保持稳健。最后,红光的远视效应在50-100勒克斯范围内的亮度水平降低时保持不变，仅在5勒克斯时失效。
结论：这些结果对理解环境红光影响屈光发育的机制具有重要意义。也可能用于使用RLRL的临床治疗。然而，目前的临床RLRL治疗的机制是否与在环境红光下对树sh进行治疗的机制相同尚待确定.
