血啉甲醚光动力疗法治疗兔脉络膜黑色素瘤的实验研究

目的探讨国产新型光敏剂血啉甲醚光动力疗法（PDT）治疗兔脉络膜黑色素瘤的效果。方法选择46只新西兰白兔（46只眼）建立脉络膜黑色素瘤模型。每日注射环孢素A以抑制免疫反应,用间接检眼镜和B超观察肿瘤生长,至瘤体为1．5～4．6mm厚度时,将46只兔（46只眼）分成两组,实验组41只眼,均静脉给予血啉甲醚10mg／kg体重,3h后用波长为630nm的氦氖激光进行照射,激光能量60～150J／cm^2。对照组5只眼,其中1只眼为空白对照,2只眼为血啉甲醚对照,2只眼为激光照射对照。PDT治疗后通过间接检眼镜、B超、彩色眼底照相观察瘤体变化4～5周,实验组16只眼分别在激光照射后24h和1周时处死,摘取眼球做病理检查,以观察疗效。结果实验组中,当激光能量≥70J／cm^2时,肿瘤生长受到明显抑制,其厚度明显缩小;在激光能量为60J／cm^2照射下,仅有部分肿瘤生长受到抑制。对照组兔眼肿瘤均在2～3周内迅速增大,甚至充满整个玻璃体腔。结论国产光敏剂血啉甲醚光动力疗法对脉络膜黑色素瘤具有一定治疗作用。

Photodynamic therapy of pigmented choroidal melanomas in rabbits using hematoporphyrin monomethyl ether

OBJECTIVE: The purpose is to determine the effectiveness of photodynamic therapy of experimental choroidal melanoma in rabbits using hematoporphyrin monomethyl ether (HMME). METHODS: Pigmented choroidal melanomas were established in 46 New Zealand albino rabbit eyes. The animals were treated with daily injection of cyclosponine A. The tumors were followed up with funduscopic examination and ultrasonography until they were 1.5 to 4.6 mm in height. Then the rabbits were divided randomly into two groups. In the treatment group, 41 rabbits were injected intravenously with hematoporphyrin monomethyl ether (HMME, 10 mg/kg). 3 hours later, the tumors were irradiated at 630 nm through an He-Ne laser at estimated total light doses of 60 approximately 150 J/cm(2). Control animals (5 rabbit eyes) were treated with light only (2 rabbit eyes), photosensitizer only (2 rabbit eyes), or observation only (1 rabbit eyes). Each animal then was followed up for 4 to 5 weeks with indirect ophthalmoscopy, ultrasonography, and fundus photography (16 rabbit eyes among the treatment group were extirpated for pathologic examination 24 hours or 1 week after the treatment). In the end, all the rabbits were sacrificed and the pathologic examinations were performed. RESULTS: With the fluences of >or= 70 J/cm(2), all the tumors regressed evidently. With the fluence of 60 J/cm(2), not all the animals showed complete tumor arrest. In the control group, all the tumors showed continuous growth and filled most of the vitreous cavity in 2 to 3 weeks. CONCLUSION: The photodynamic therapy with homemade photosensitizer HMME may have a role in the treatment of pigmented choroidal melanomas.