Combination therapy for malignant brain tumor model using the stereotactic laser hyperthermia and the new photodynamic therapy

对于立体激光热疗，将Ultra Line^<TM>光纤（贺利氏激光超声公司，CA）插入6F硅胶球囊导管，用生理盐水充气，使激光光纤周围的肿瘤组织缺氧。缺氧增强了对肿瘤的热效应。将激光功率设置为5瓦，在温度为45ºC的条件下，将组织与激光光纤保持10mm的距离。对大鼠植入式皮下胶质瘤进行45分钟的高温治疗。结果：肿瘤热致损伤呈扇形病变，以100‰的角度向外延伸。通过旋转球囊导管内的激光纤维，可以治疗整个肿瘤。针对新的光动力疗法，用表皮样癌细胞制作脑肿瘤模型。光动力疗法采用Exima染料激光器（Hamamatsu Photonics k.k., Japan）。脑肿瘤MRI确诊后，静脉注射光叶素^<<环绕dr >> (4mg/Kg)。激光经皮照射150焦耳。4天后，组织学检查显示肿瘤在距皮质12mm处出现凝固性坏死。由于激光热疗的边界呈波浪形区，联合治疗对边界区域的肿瘤是有效的。结论：联合治疗颅内小恶性肿瘤（直径小于10mm）创伤小、治疗彻底。

To the stereoctic laser hyperthermia, an Ultra Line^<TM> fiber (Heraeus Laser Sonics, CA) was inserted into a 6F silicone balloon catheter, which was inflated with physiologic saline to make the tumor tissue surrounding the laser fiber hypoxic. The hypoxia enhances the thermal effect on the tumor. The laser power was set at 5 watts and a computer, programd with specific parameters using feedback control was used to maintain the tissue 10 mm distant from the laser fiber at a temperature of 45ﾟC.Forty five minutes of hyperthermic treatment was applied to an implanted subcutaneous glioma in rat.Results : The thermal induced damaged in the tumor appeared as a fan-shaped lesion extending at a 100ﾟ angle from the laser beam axis. The entire tumor could be treated by rotating the laser fiber in the balloon catheter.To the new photodynamic therapy, the brain tumor model was made with epidermoid carcinoma cells. The photodyramic therapy was used Exima Dye Laser (Hamamatsu Photonics K.K., Japan).After the brain tumor was confirmed by MRI,the photophyrin^<<encircledR>> (4mg/Kg) was injected into the vein. The Laser was irradiated with 150 Joule percutaneously. After four days, the histological examination revealed the coagulation mecrosis of the tumor within the 12 mm from the cortex.As the boderline by the laser hyperthermic treatment showed the wave-shaped zone, the combination therapy is effective to treat the tumor at the border line area.Conclusion : These showed that the small intracranial malignant tumor (within 10 mm in diameter) can treated by using the combination therapy in less invasively and completly.