光敏剂漂白特性在鲜红斑痣光动力治疗中的作用

Effect of Photosensitizer Photobleaching on Vascular Selectivity of Photodynamic Therapy

目的 监测光动力治疗过程中鲜红斑痣组织内光敏剂含量的动态变化 ,探讨光敏剂漂白特性在光动力疗法微血管选择机制中的作用。方法 鲜红斑痣病人 34例 ,男性 15例 ,女性 19例 ,静脉注射血啉甲醚和血卟啉衍生物 5mg/kg后给予铜蒸气激光照射。使用三倍频Nd∶YAG激光和光学多通道分析仪 (OMA)在治疗前和治疗中的多个时间点对治疗区皮肤组织进行荧光光谱检测 ,绘制成时间 -荧光强度曲线。结果 治疗区皮肤组织中光敏剂荧光强度在激光照射开始后迅速下降 ,血啉甲醚荧光强度的下降速率和下降幅度均显著大于血卟啉衍生物。结论 治疗区皮肤组织中光敏剂的漂白速度明显大于光敏剂的补充扩散速度 ,光敏剂漂白可能是光动力疗法微血管选择效应的主要机制。

Objective To investigate the photobleaching characteristics of hematoporphyrin monomethyl ether(HMME) and hematoporphyrin derivative (HpD), and to assess the relationship between photosensitizer photobleaching and vascular selective mechanism of photodynamic therapy (PDT). Methods Thirty four port wine stain(PWS) patients were irradiated by copper vapor laser with power densities 100 mW/cm 2 and energy densities from 200 to 300 J/cm 2 after 5 mg/kg HMME or HpD intravenous injection. Photosensitizer fluorescenece of tissue was excited by Nd∶YAG laser (wavelength 355 nm) and analyzed by using an optical multichannel analyzer (OMA). Results The fluorescenece intensity of photosensitizer in superficial layers of PWS skin descended rapidly after laser irridiation. The descent speed and amplitude of fluorescenece intensity of HMME was more than that of HpD. Conclusions The photobleaching speed of photosensitizer in PWS skin was quicker than the diffusion speed of photosensitizer, and the photobleaching characteristics of photosensitizer was very important for vascular selective effect of PDT.