Poptani H, Duvvuri U, Miller C G, Mancuso A, Charagundla S, Fraser N W, Glickson J D, Leigh J S, Reddy R
Department of Radiology, University of Pennsylvania, Philadelphia, USA.
Acad Radiol. 2001 Jan;8(1):42-7. doi: 10.1016/S1076-6332(03)80742-0.
The goal of this study was to evaluate the utility of T1rho weighting in magnetic resonance imaging of murine brain tumors.
S91 Cloudman melanoma was implanted in mouse brains (n = 4). A T2-weighted spin-echo (SE) and a T1rho-weighted fast SE-based sequence were performed on a 4-T clinical imager. T2 and T1rho maps were computed. The tumor-to-normal-tissue contrast was compared between T2-weighted, T1rho-weighted, proton-density-weighted, and pre- and postcontrast T1-weighted SE images.
The tumor-tissue contrast of the T1rho-weighted images was similar to that of the T2-weighted images but less than that of the postcontrast T1-weighted images. The T1rho-weighted images provided better definition of tumor boundaries than T2-weighted images. At spin-locking powers of 0.5 and 1.5 kHz, the T1rho of the tumor was 64.0 msec +/- 0.46 and 68.65 msec +/- 0.59, respectively. There was no significant inter- or intra-animal variation in T1rho for tumor or normal brain cortex.
T1rho-weighted imaging performed at low spin-lock strengths qualitatively depicted tumor borders better than proton-density or T2-weighted imaging and could be useful in treatment planning when combined with other imaging sequences.
本研究的目的是评估T1rho加权在小鼠脑肿瘤磁共振成像中的效用。
将S91 Cloudman黑色素瘤植入小鼠脑内（n = 4）。在一台4-T临床成像仪上进行T2加权自旋回波（SE）和基于T1rho加权的快速SE序列成像。计算T2和T1rho图。比较T2加权、T1rho加权、质子密度加权以及对比剂注射前后T1加权SE图像上肿瘤与正常组织的对比度。
T1rho加权图像的肿瘤组织对比度与T2加权图像相似，但低于对比剂注射后T1加权图像。T1rho加权图像比T2加权图像能更好地显示肿瘤边界。在自旋锁定功率为0.5和1.5 kHz时，肿瘤的T1rho分别为64.0毫秒±0.46和68.65毫秒±0.59。肿瘤或正常脑皮质的T1rho在动物间和动物内均无显著差异。
在低自旋锁定强度下进行的T1rho加权成像在定性描绘肿瘤边界方面比质子密度或T2加权成像更好，并且与其他成像序列联合使用时可能对治疗规划有用。
