使用表面线圈的磁共振成像中自旋-自旋质子弛豫时间的双指数分析

Two-exponential analysis of spin-spin proton relaxation times in MR imaging using surface coils.

作者信息

Schad L R, Brix G, Semmler W, Gückel F, Lorenz W J

机构信息

Institute of Radiology and Pathophysiology, German Cancer Research Center, Heidelberg.

出版信息

Magn Reson Imaging. 1989 Jul-Aug;7(4):357-62. doi: 10.1016/0730-725x(89)90484-0.

DOI:10.1016/0730-725x(89)90484-0

PMID:2554085

Abstract

Proton relaxation time measurements were performed on a standard whole body MR imager operating at 1.5 T using a conventional surface coil of the manufacturer. A combined CP/CPMG multiecho, multislice sequence was used for the T1 and T2 relaxation time measurements. Two repetition times of 2000 ms (30 echoes) and 600 ms (2 echoes) with 180 degrees-pulse intervals of 2 tau = 22 ms were interleaved in this sequence. A two-exponential T2 analysis of each pixel of the spin-echo images was computed in a case of an acoustic neurinoma. The two-exponential images show a "short" component (T2S) due to white and gray matter and a "long" component (T2S) due to the cerebrospinal fluid. In the fatty tissue two components with T2S = 35 +/- 3 ms and T2L = 164 +/- 7 ms were measured. Comparing with Gd-DTPA imaging the relaxation time images show a clear differentiation of vital tumor tissue and cerebrospinal fluid.

摘要

使用制造商的传统表面线圈，在一台1.5T的标准全身磁共振成像仪上进行质子弛豫时间测量。采用CP/CPMG组合多回波、多层序列进行T1和T2弛豫时间测量。在该序列中交错使用两个重复时间，分别为2000ms（30个回波）和600ms（2个回波），180度脉冲间隔为2τ = 22ms。对于听神经瘤病例，对自旋回波图像的每个像素进行双指数T2分析。双指数图像显示，由于白质和灰质产生一个“短”成分（T2S），由于脑脊液产生一个“长”成分（T2L）。在脂肪组织中，测量到两个成分，T2S = 35±3ms，T2L = 164±7ms。与钆喷酸葡胺成像相比，弛豫时间图像清晰地显示了存活肿瘤组织和脑脊液的差异。