植入乳腺腺癌的大鼠在0.063 - 4.85特斯拉磁场下的体内弛豫时间和氢密度

In vivo relaxation times and hydrogen density at 0.063-4.85 T in rats with implanted mammary adenocarcinomas.

作者信息

Chen J H, Avram H E, Crooks L E, Arakawa M, Kaufman L, Brito A C

机构信息

Radiologic Imaging Laboratory, University of California, San Francisco 94080.

出版信息

Radiology. 1992 Aug;184(2):427-34. doi: 10.1148/radiology.184.2.1620841.

DOI:10.1148/radiology.184.2.1620841

PMID:1620841

Abstract

Magnetic resonance (MR) imaging at 0.063 T, 0.17 T, 0.35 T, 2.94 T, and 4.85 T was performed in rats with implanted mammary adenocarcinomas (and in control rats) to study hydrogen density and the effects of magnetic field strength on T1 and T2 relaxation times in vivo. T1 increased by an order of magnitude and T2 decreased by a factor of two between the lowest and highest field strengths. Only about half of the increased water content of tumor, compared with that of muscle, was reflected in increased hydrogen density. The sensitivity of relaxation time change was increased at the lower field strengths. These results are of significance in understanding the effects of field strength on lesion detectability, contrast, and signal-to-noise ratio.

摘要

对植入乳腺腺癌的大鼠（以及对照大鼠）进行了0.063 T、0.17 T、0.35 T、2.94 T和4.85 T的磁共振（MR）成像，以研究氢密度以及磁场强度对体内T1和T2弛豫时间的影响。在最低和最高场强之间，T1增加了一个数量级，T2减少了一半。与肌肉相比，肿瘤增加的含水量中只有约一半反映在氢密度增加上。在较低场强下，弛豫时间变化的敏感性增加。这些结果对于理解场强对病变可检测性、对比度和信噪比的影响具有重要意义。