High resolution MR imaging of the knee at 3T

目的。检查3.0-T磁共振设备以获得高质量、高分辨率的膝关节图像。一个人的身体和五个猪的膝盖用3.0-T设备进行了成像。获得了几组T1加权自旋回波图像，面内分辨率为0.195x0.39 mm，采集时间约为5min。用1.0-T成像机以相同的成像方案对猪的两个膝关节进行成像，并在3T和1T时测量图像的信噪比。3-T磁共振系统提供了膝关节的详细轮廓。内侧副韧带的深层以及内侧副韧带和外侧副韧带下的相关细小纤维被划定。精确显示前交叉韧带的胫骨附着，半月板游离缘的不规则，以及与外侧副韧带和股二头肌肌腱一起的联合肌腱形成。与1-T单元相比，3-T单元的信噪比提高1.39倍至1.72倍。由于获得详细图像的潜在优势，3-T磁共振系统建议用于精细显示膝关节形态的实用价值。

Purpose. To examine the 3.0-T MR unit to obtain high quality, high resolution images of the knee joint.Subjects and Methos. One human cadaveric and five porcine knees were imaged with the 3.0-T unit. Sets of T1-weighted spin echo images were obtained with in-plane resolution of 0.195x0.39mm and an acquisition time of approximately 5min. Two porcine knees were also imaged with the 1.0-T unit with an identical imaging protocol and the signal-to-noise ratios were measured on both images at 3T and 1T.Results. The 3-T MR system provided detailed delineation of the knees. Deep layers of the medial collateral ligament and associated fine fibers beneath the medial and lateral collateral ligament were demarcated. Precise demonstration of the tibial attachment of the anterior cruciate ligament, irregularity of the meniscal free edge, and conjoint tendon formation together with the lateral collateral ligament and the biceps femoris tendon, were demonstrated. Compared to 1-T unit, the signal-to-noise ratio with 3-T was increased by a factor of 1.39 to 1.72.Conclusion. Due to the potential advantage of obtaining detailed images, the 3-T MR system suggests practical utility for fine demonstration of the knee morphology.