Engelhardt R T, Johnson G A
Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
Magn Reson Med. 1996 May;35(5):781-6. doi: 10.1002/mrm.1910350520.
The application of T1 rho an an alternative contrast parameter in high-field magnetic resonance histology (MRH) has been investigated. Spectroscopic measurements of T1 rho were performed on 5.75% agar and 1.0 mM MnCI2 phantoms at 9.4 T to validate the accuracy of the imaging measurements. Image studies were performed at 2.0 and 9.4 T on perfusion-fixed 17.5-day-old mouse embryos. T1, T2, and T1 rho relaxation times were calculated for the phantoms and muscle, diencephalon, and liver tissues. The 5.75% agar phantom and all tissues showed T1 rho dispersion with B1L, whereas the 1.0 mM MnCI2 phantom showed no significant B1L dependence. T1 rho dispersion with B(O) was observed arising from the effects of diffusion through susceptibility-induced gradients. T1 rho shows promise as a contrast parameter in high-field MRH because it is capable of producing T2-like contrast without the susceptibility artifacts associated with T2-weighted images.
已对T1 rho作为高场磁共振组织学（MRH）中一种替代对比参数的应用进行了研究。在9.4 T下对5.75%琼脂和1.0 mM MnCI2模型进行T1 rho的光谱测量，以验证成像测量的准确性。在2.0和9.4 T下对灌注固定的17.5天大的小鼠胚胎进行图像研究。计算了模型以及肌肉、间脑和肝脏组织的T1、T2和T1 rho弛豫时间。5.75%琼脂模型和所有组织均显示出与B1L相关的T1 rho色散，而1.0 mM MnCI2模型则未显示出明显的B1L依赖性。观察到由于通过磁化率诱导梯度的扩散效应而产生的与B(O)相关的T1 rho色散。T1 rho有望成为高场MRH中的一种对比参数，因为它能够产生类似T2的对比，而不会出现与T2加权图像相关的磁化率伪影。
