Waterman F M, Tupchong L, Nerlinger R E, Matthews J
Department of Radiation Oncology and Nuclear Medicine, Thomas Jefferson University Hospital, Philadelphia, PA 19107.
Int J Radiat Oncol Biol Phys. 1991 Jun;20(6):1255-62. doi: 10.1016/0360-3016(91)90236-w.
The response of tumor blood flow during local hyperthermia was studied at 40 different points in 15 superficial human tumors. Hyperthermia was administered for 60 minutes by use of 915 MHz microwaves. Blood flow was determined from the rate of thermal clearance by use of the bioheat equation. The rate of thermal clearance was sampled at 10-15 minutes intervals by turning the applied power off for 30 seconds. A correction was made for thermal conduction from orthogonal profiles of the tumor temperature. No measurements were made during the first 10-15 minutes of heating. The response of tumor blood flow was found to be independent of temperature in the range of 40-44 degrees C. The mean blood flow rate increased 10-15% between 15 and 30 minutes, but remained nearly constant thereafter. The coefficient of variation in this pattern is 15-20%. No evidence of a sharp reduction in flow was observed. Furthermore, the mean temperature elevation, net forward power, and rate of thermal conduction all remained nearly constant with time, providing further evidence of stability in the blood flow rate. Data obtained in one tumor suggest that a reduction in flow may occur at temperatures above 44 degrees C. The mean blood flow rates obtained in this study range from 0-34 ml/100g/min with an average value of 15 ml/100g/min.
在15例人体浅表肿瘤的40个不同部位研究了局部热疗期间肿瘤血流的反应。使用915兆赫微波进行60分钟的热疗。利用生物热方程根据热清除率测定血流。通过关闭施加功率30秒，以10 - 15分钟的间隔对热清除率进行采样。对肿瘤温度的正交剖面的热传导进行了校正。在加热的前10 - 15分钟内未进行测量。发现在40 - 44摄氏度范围内肿瘤血流的反应与温度无关。平均血流速率在15至30分钟之间增加了10 - 15%，但此后几乎保持恒定。这种模式的变异系数为15 - 20%。未观察到血流急剧减少的迹象。此外，平均温度升高、净向前功率和热传导速率均随时间几乎保持恒定，进一步证明了血流速率的稳定性。在一个肿瘤中获得的数据表明，在温度高于44摄氏度时可能会出现血流减少。本研究中获得的平均血流速率范围为0 - 34毫升/100克/分钟，平均值为15毫升/100克/分钟。
