不同参数竹红菌乙素-光动力治疗对兔脉络膜毛细血管层的生物学效应(英文)

Biological effect of hypocrellin B-photodynamic therapy with different parameters on choriocapillaris in rabbits

背景世界各国都在进行光敏剂开发,治疗脉络膜新生血管(CNV)疾病的工作,本实验是国内少数几家利用国产光敏剂治疗CNV之一。目的观察不同治疗参数竹红菌乙素-光动力治疗(HB-PDT)对青紫蓝兔脉络膜毛细血管层生物学效应以及对视网膜的非选择性损伤,选择适宜PDT治疗方案,为进一步探讨HB-PDT治疗CNV提供先期研究工作。设计随机对照的实验研究。地点和材料实验在北京解放军总医院和北京理工大学完成,以青紫兰兔为实验材料。干预使用光纤连接532nm激光器和裂隙灯显微镜,作为照射系统。青紫兰兔耳缘静脉内注射竹红菌乙素,532nm光线激发光敏剂。使用不同PDT方案进行实验,每组实验眼3例,同时以单纯照光组和单照药物组作为对照。主要观察指标PDT后第1天行视网膜观察、荧光眼底造影和组织学检查,观察照光部位及其表面正常组织的变化。结果在PDT后第1天,单纯照光组和单纯药物对照组眼底和组织学无改变;在HB剂量为1.0mg/kg,532nm连续激光激发光敏剂,功率密度120～700mW/cm2,能量密度14.4～60J/cm2,可以导致脉络膜毛细血管层的闭塞,对视网膜外层有损害,内层无明显改变。HB剂量1.0mg/kg,功率密度300～600mW/cm2,照光时间100～80s,能量密度30～50J/cm2是适宜的治疗方案。

BACKGROUND:Photosensitizer is developed for the treatment of choroidal neovascularization(CNV),which is conducted all over the world.Our study is one of the few national researches that use domestic photosensitizer to treat CNV.OBJECTIVE:To observe the biological effect of hypocrellin B photodynamic therapy(HB PDT) on the choroid and the non selective injury on retina with different therapeutic parameters in rabbit to judge the optimal PDT plan for providing some elementary study in further investigation of HB PDT in the treatment of CNV.DESIGN:A randomized controlled trialSETTING and PARTICLPANTS:Study was conducted in Beijing PLA General Hospital and Beijing University of Technology and Engineering.Experimental subjects were Chichilan Rabbits.INTERVENTIONS:A total of 532 nm laser and Slit Lamp Biomicroscope connected by fibre were set as the irradiation system.HB was injected into the auricle marginal vein of Chichilan rabbits. Photosensitizer was stimulated by 532 nm laser.Different PDT plans were used in the study with 3 cases in each group.MAIN OUTCOME MEASURES:On the 1st day after PDT,the changes of the irradiated sites and the normal tissue on its surface were observed by retinal photography,fluorescent angiography and histological examination.RESULTS:There is no structural change in light only control group and the photosensitizer only control group on the 1st day after PDT.The occlusion of choriocapillaris was induced when the HB dose was 1.0 mg/kg,power density was 120-700 mW/cm2,and energy density was 14.4-60 J/cm2,which caused the damage to the outer retina but no significant changes in the inner retina.The optimal therapeutic parameter was when HB dose was 1.0 mg/kg,power density was 300-600 mW/cm2 and energy density was 14.4-48 J/cm2.CONCLUSION:The biological effect of HB on retina and choroid closely correlates to the dose of photosensitizer,timing of the irradiation,power density and energy density.There is a dose effect relationship between biological effect and energy density.