Imaging end-stage kidney disease in adults - Low-field MR imaging with magnetization transfer vs. ultrasonography

Purpose: To 1) assess the potential of magnetization transfer (MT)-weighted MR imaging to improve the often poor visibility of native kidneys in patie nts with a renal transplant; and 2) compare low-held MR imaging and ultraso nography (US) for imaging these fibrotic kidney remnants. Material and Methods: Seventy-two native kidneys of 36 patients were prospe ctively evaluated with US and MR. In low-field (0.1 T) MR imaging, T1-, T2- and MT-weighted sequences were used. MT-weighted images were compared with T2-weighted images in their ability to delineate the kidneys from their su rroundings whereas US and MR were compared for detection of renal cysts and possible solid tumors. Results. MT-weighted images proved superior to conventional T2-weighted ima ges in producing contrast between the kidney remnants and their fatty surro undings, Although US revealed a few small renal cysts that were not seen at MR images, no statistical difference was found between the two modalities in this respect. Conclusion: MT imaging, due to its unique protein-specific signal depressio n, offers significantly improved Visualization and delineation of end-stage kidneys. US, because its better availability and cost-benefit ratio, remai ns the method-of-choice compared to low-field MR imaging in detecting cysts in multicystic kidneys. MR investigation is helpful in selected patients a nd may be used as an alternative.