Department of Medical Imaging, The Ottawa Hospital, The University of Ottawa, Ottawa, ON, Canada.
Department of Radiology, NYU Langone Health, New York, USA.
Abdom Radiol (NY). 2019 Dec;44(12):3800-3810. doi: 10.1007/s00261-019-02085-1.
Magnetic resonance imaging of the upper tract (pyelocalyces and ureters) or MR Urography (MRU) is technically possible and when performed correctly offers similar visualization of the upper tracts and for detection of non-calculous diseases of the collecting system similar specificity but with lower sensitivity compared to CTU. MRU provides the ability to simultaneously image the kidneys and urinary bladder with improved soft tissue resolution, better tissue characterization and when combined with assessment of the upper tract, a comprehensive examination of the urinary system. MRU requires meticulous attention to technical details and is a longer more demanding examination compared to CTU. Advances in MR imaging techniques including: parallel imaging, free-breathing motion compensation techniques and compressed sensing can dramatically shorten examination times and improve image quality and patient tolerance for the exam. This review article discusses updates in the MRU technique, summarizes clinical indications and opportunities for MRU in clinical practice and reviews advantages and disadvantages of MRU compared to CTU.
上尿路（肾盂和输尿管）磁共振成像或磁共振尿路成像（MRU）在技术上是可行的，当正确执行时，它可以提供类似的上尿路可视化效果，并具有与 CTU 相似的特异性，用于检测非结石性收集系统疾病，但敏感性较低。MRU 提供了同时对肾脏和膀胱成像的能力，具有改善的软组织分辨率、更好的组织特征，并且当与上尿路评估相结合时，可以对泌尿系统进行全面检查。MRU 需要对技术细节进行细致的关注，与 CTU 相比，它是一项更长、更具挑战性的检查。磁共振成像技术的进步，包括并行成像、自由呼吸运动补偿技术和压缩感知技术，可以显著缩短检查时间，提高图像质量和患者对检查的耐受性。本文综述了 MRU 技术的最新进展，总结了 MRU 在临床实践中的适应证和应用机会，并比较了 MRU 与 CTU 的优缺点。
