Kroeker R M, Stewart C A, Bronskill M J, Henkelman R M
Department of Medical Biophysics, University of Toronto, Ontario, Canada.
Magn Reson Med. 1988 Jan;6(1):24-36. doi: 10.1002/mrm.1910060104.
In vivo measurements of T1 and T2 values in two experimental tumors growing in the legs of mice were made during tumor growth and after treatment of the tumor with either X-rays or cyclophosphamide. The T1 and T2 values were obtained by fitting the data to continuous distributions of relaxation times. This technique gives broad distributions of relaxation times which are characterized by a number of peaks with characteristic T1 and T2 values. Before treatment, the T1 and T2 values increased before a palpable tumor mass could be detected. The response to subcurative doses of either treatment method was a reduction in the T1 and T2 values and a parallel reduction in tumor weight. Although local recurrence was characterized by the same pattern of tumor growth as was observed before treatment, therapy was found to give higher relaxation time values than those measured in untreated tumors. The higher relaxation time values of tumor-bearing legs were the result of redistribution of the peaks in the distribution and not changes in the relaxation times of the individual peaks.
在小鼠腿部生长的两种实验性肿瘤的T1和T2值的体内测量是在肿瘤生长期间以及用X射线或环磷酰胺治疗肿瘤后进行的。通过将数据拟合到弛豫时间的连续分布来获得T1和T2值。该技术给出了弛豫时间的广泛分布，其特征在于具有特征性T1和T2值的多个峰。在治疗前，在可触及肿瘤块之前T1和T2值就升高了。两种治疗方法的亚治愈剂量的反应是T1和T2值降低以及肿瘤重量平行降低。尽管局部复发的特征是与治疗前观察到的相同的肿瘤生长模式，但发现治疗后的弛豫时间值高于未治疗肿瘤中的测量值。荷瘤腿部较高的弛豫时间值是分布中峰重新分布的结果，而不是各个峰的弛豫时间的变化。
