Yamada K, Shrier D A, Rubio A, Yoshiura T, Iwanaga S, Shibata D K, Patel U, Numaguchi Y
Department of Diagnostic Radiology, University of Rochester Medical Center, NY 14642, USA.
Radiology. 1998 Jun;207(3):593-8. doi: 10.1148/radiology.207.3.9609878.
To demonstrate the normal and abnormal appearance of the mamillothalamic tract (MTT) on cranial magnetic resonance (MR) images.
Two formalin-fixed normal human brain specimens sectioned in axial and coronal planes were used to demonstrate the normal anatomy of the MTT. MR images were obtained in 32 volunteers. Proton-density-weighted coronal and axial pulse sequences were used. The images were evaluated for visualization quality and size and signal intensity of the MTTs in correlation with the specimens. Abnormal MTTs were identified on cranial MR images in two patients, and the imaging findings were analyzed. The clinical history of the patients was also reviewed to determine the effect of these findings on patient care.
Normal MTTs were easily identified on MR studies of cadaveric brains and of the brains of the human volunteers. On MR images, normal MTTs were commonly symmetric in appearance, with signal intensity equal to that of other normal fiber tracts. The abnormal MTTs showed high signal intensity on images obtained with a long repetition time or asymmetric volume loss and were associated with atrophy of the ipsilateral mamillary body.
Normal MTTs are readily visible on conventional MR images. Abnormality of the MTT is a very subtle finding but may be a marker of a limbic system abnormality.
在头颅磁共振（MR）图像上显示乳头丘脑束（MTT）的正常及异常表现。
使用两个在轴向和冠状面切片的福尔马林固定的正常人类脑标本，以显示MTT的正常解剖结构。对32名志愿者进行了MR成像。采用质子密度加权冠状和轴向脉冲序列。评估图像的可视化质量以及MTT的大小和信号强度，并与标本进行对比。在两名患者的头颅MR图像上发现了异常的MTT，并对影像学表现进行了分析。还回顾了患者的临床病史，以确定这些发现对患者治疗的影响。
在尸体脑和人类志愿者脑的MR研究中，正常的MTT很容易识别。在MR图像上，正常的MTT通常外观对称，信号强度与其他正常纤维束相同。异常的MTT在长重复时间获得的图像上显示高信号强度或不对称体积减小，并与同侧乳头体萎缩有关。
正常的MTT在常规MR图像上很容易看到。MTT的异常是一个非常细微的发现，但可能是边缘系统异常的一个标志。
