Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400 Copenhagen, Denmark.
Int J Mol Sci. 2016 Feb 29;17(3):309. doi: 10.3390/ijms17030309.
Daylight-mediated photodynamic therapy (daylight PDT) is a simple and pain free treatment of actinic keratoses. Weather conditions may not always allow daylight PDT outdoors. We compared the spectrum of five different lamp candidates for indoor "daylight PDT" and investigated their ability to photobleach protoporphyrin IX (PpIX). Furthermore, we measured the amount of PpIX activating daylight available in a glass greenhouse, which can be an alternative when it is uncomfortable for patients to be outdoors. The lamps investigated were: halogen lamps (overhead and slide projector), white light-emitting diode (LED) lamp, red LED panel and lamps used for conventional PDT. Four of the five light sources were able to photobleach PpIX completely. For halogen light and the red LED lamp, 5000 lux could photobleach PpIX whereas 12,000 lux were needed for the white LED lamp. Furthermore, the greenhouse was suitable for daylight PDT since the effect of solar light is lowered only by 25%. In conclusion, we found four of the five light sources and the greenhouse usable for indoor daylight PDT. The greenhouse is beneficial when the weather outside is rainy or windy. Only insignificant ultraviolet B radiation (UVB) radiation passes through the greenhouse glass, so sun protection is not needed.
日光介导的光动力疗法（日光 PDT）是一种简单且无痛的治疗光化性角化病的方法。但天气条件并不总是允许在户外进行日光 PDT。我们比较了五种不同的室内“日光 PDT”候选灯的光谱，并研究了它们对原卟啉 IX（PpIX）的光漂白能力。此外，我们还测量了玻璃温室中可用的激活日光的 PpIX 量，当患者在户外感到不适时，这可以作为替代方法。所研究的灯包括：卤素灯（头顶灯和幻灯机）、白色发光二极管（LED）灯、红色 LED 灯板以及用于传统 PDT 的灯。五种光源中的四种能够完全光漂白 PpIX。对于卤素灯和红色 LED 灯，需要 5000 勒克斯才能光漂白 PpIX，而白色 LED 灯则需要 12000 勒克斯。此外，温室适合进行日光 PDT，因为太阳光的影响仅降低了 25%。总之，我们发现五种光源中的四种和温室可用于室内日光 PDT。当室外天气多雨或刮风时，温室很有用。只有少量的紫外线 B 辐射（UVB）能够穿透温室玻璃，因此不需要防晒。
