兔脉络膜黑色素瘤光动力学治疗的研究

Photodynamic therapy of pigmented choroidal melanomas in rabbits

目的 评价第二代光敏物质 (benzoporphyrinderivative ,BPD)在兔脉络膜色素性黑色素瘤光动力学治疗中的疗效。方法 对 4 4只新英格兰大白兔眼 ,建立脉络膜色素性黑色素瘤模型 ,每日注射环孢素A行免疫抑制治疗。当黑色素瘤生长厚度达 2 0～ 4 6mm时 ,将 4 4只兔分成 3组 ,治疗Ⅰ组 (14只兔 )及治疗Ⅱ组 (2 0只兔 ) ,静脉给予BPD 1mg/kg ,通过氩离子 染料激光进行光动力学治疗 ,波长为 6 92nm ,照射剂量为 6 0～ 15 0J/cm2 ;对照组 (10只兔 )中的 6只兔仅给予激光照射 ,4只兔为空白对照。治疗后 4～ 6周处死兔 ,取其眼球观察脉络膜黑色素瘤光动力学治疗效果。结果 34只脉络膜黑色素瘤兔经光动力学治疗后 ,治疗Ⅰ组肿瘤厚度为 <3mm ,激光照射剂量 6 0～ 80J/cm2 ,与对照组比较 ,差异有非常显著意义 (P <0 0 0 1) ;治疗Ⅱ组肿瘤厚度为 3 0～ 4 6mm ,激光照射剂量为 >80J/cm2 ,与对照组比较 ,差异有非常显著意义 (P <0 0 0 1)。对照组兔眼肿瘤在 2～ 3周时充满整个玻璃体腔。

Objective To evaluate the effect of photo dynamic therapy in the destruction of experimental pigmented choroidal melanoma using a liposomal preparation of benzoporphyrin derivative (BPD), verteporfin. Methods Pigmented choroidal tumors were established in 44 New Zealand albino rabbit eyes. Animals were treated with daily injections of cyclosporine. Funduscopic examinations and ultrasonography were used to follow the tumor growth. When the tumor exceeded 2 mm in thickness (tumor height ranged from 2 0-4 6 mm), the rabbits were divided into three groups. In the 10 rabbits in the control group, 6 were treated with laser 120-150 J/cm 2 for tumors with the height range of 2 1-3 0 mm without photo dynamic therapy, and 4 were not treated at all. The benzoporphyrin derivative was injected intravenously (1 mg/kg) for the rabbits in treatment groupⅠ(14 rabbits) and Ⅱ (20 rabbits), and 692 nm argon pumped dye laser at different light doses 60-150 J/cm 2 was used to irradiate the tumors. After the treatment for 4-6 weeks, the rabbits were sacrificed and the therapeutic results were observed. Results In treatment group I, the irradiation dose was 60-80 J/cm 2 and the tumor height was <3 mm, in comparison with that of the control group the difference being very significant ( P <0.001). In the treatment group Ⅱ, the thickness of the tumor was 3 0-4 6 mm and the irradiation dose was >80 J/cm 2( P <0 001, companed with the control group). In contrast, the tumor grew continuously in all the animals in the control group and filled most of the vitreous cavity by 2-3 weeks. Conclusion These data suggest that photodynamic therapy have a role in the management of pigmented choroidal melanomas