Tanaka K, Kikuchi Y, Yamada Y
Central Laboratory for Research & Education, Asahikawa Medical College, Japan.
Med Biol Eng Comput. 1995 Jan;33(1):38-43. doi: 10.1007/BF02522943.
Proton spin-lattice relaxation time T1 of the localised tumour portion and its neighbouring portion of tumour-bearing mice legs is successively observed before and after radiotherapy by applying the previously proposed magnetic focusing method. Changes in T1 values are also compared with the histological radiation effects. For un-irradiated tumours, T1 increases gradually with tumour growth. T1 of the tumour portion shows significant decrease after radiotherapy. The decrease in the T1 values of the tumour clearly depends on the single radiation dose of 30, 45 and 60 Gy, respectively. A rapid decrease in the T1 values of the tumour occurs prior to the decrease in tumour volume. These decreases in the T1 values of the tumour after radiotherapy correspond positively to the increase of the histological radiation effects. After the reduction in the T1 values of the irradiated tumour portion, a successive increase in T1 values is observed and suggests local recurrence of the tumour. These results show that localised T1 relaxation time is a good reflection of the tissue response to radiotherapy.
通过应用先前提出的磁聚焦方法，在放疗前后相继观察荷瘤小鼠腿部局部肿瘤部分及其相邻部分的质子自旋晶格弛豫时间T1。还将T1值的变化与组织学辐射效应进行比较。对于未照射的肿瘤，T1随肿瘤生长而逐渐增加。放疗后肿瘤部分的T1显著降低。肿瘤T1值的降低明显分别取决于30、45和60 Gy的单次辐射剂量。肿瘤T1值的快速降低发生在肿瘤体积减小之前。放疗后肿瘤T1值的这些降低与组织学辐射效应的增加呈正相关。照射后肿瘤部分的T1值降低后，观察到T1值相继增加，提示肿瘤局部复发。这些结果表明，局部T1弛豫时间很好地反映了组织对放疗的反应。
