Ji Y, Walstad D, Brown J T, Powers S K
Division of Neurosurgery, University of North Carolina, Chapel Hill 27599-7060.
Photochem Photobiol. 1992 Sep;56(3):385-90. doi: 10.1111/j.1751-1097.1992.tb02175.x.
The effectiveness of intratumoral photoradiation in photodynamic therapy (PDT) using a polyporphyrin photosensitizer was studied in the RT-2 rat glioma model. One week after intracerebral implantation of RT-2 cells, experimental rats received a single i.p. injection of 2 mg/kg of Photofrin. After administration of the photosensitizer (48 h), the tumors were partially resected and the exposed cavity was irradiated with 15 J of laser light at a wavelength of 630 nm. Further treatment with a large craniectomy significantly enhanced rat survival. Control rats which received no photosensitizer but were treated with surgery, alone or in combination with laser irradiation, succumbed from early tumor recurrence. Photodynamic therapy without decompressive surgery resulted in hemorrhagic infarction of residual tumor and adjacent brain with focal cerebral edema which resulted in cerebral herniation and early death. Our results indicate that photodynamic therapy is effective in treating residual brain tumor but at the expense of brain tissue surrounding the tumor. Unless relieved, intracranial pressure from photodynamic therapy-associated cerebral edema in this animal model resulted in shortened survival.
在RT-2大鼠胶质瘤模型中，研究了使用聚卟啉光敏剂的瘤内光辐射在光动力疗法（PDT）中的有效性。在脑内植入RT-2细胞一周后，实验大鼠腹腔注射一次2 mg/kg的卟吩姆钠。给予光敏剂后（48小时），对肿瘤进行部分切除，并用波长为630 nm的15 J激光照射暴露的腔隙。进一步进行大骨瓣切除术显著提高了大鼠的生存率。未接受光敏剂但仅接受手术或手术联合激光照射的对照大鼠因早期肿瘤复发而死亡。未进行减压手术的光动力疗法导致残留肿瘤和邻近脑组织出血性梗死，并伴有局灶性脑水肿，进而导致脑疝和早期死亡。我们的结果表明，光动力疗法在治疗残留脑肿瘤方面是有效的，但以牺牲肿瘤周围的脑组织为代价。在该动物模型中，除非得到缓解，光动力疗法相关脑水肿引起的颅内压会导致生存期缩短。
