Imaging end-stage kidney disease in adults. Low-field MR imaging with magnetization transfer vs. ultrasonography.
OBJECTIVE
To 1) assess the potential of magnetization transfer (MT)-weighted MR imaging to improve the often poor visibility of native kidneys in patients with a renal transplant; and 2) compare low-field MR imaging and ultrasonography (US) for imaging these fibrotic kidney remnants.


METHODS
Seventy-two native kidneys of 36 patients were prospectively 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 surroundings 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 images in producing contrast between the kidney remnants and their fatty surroundings. 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.


CONCLUSIONS
MT imaging, due to its unique protein-specific signal depression, offers significantly improved visualization and delineation of end-stage kidneys. US, because its better availability and cost-benefit ratio, remains the method-of-choice compared to low-field MR imaging in detecting cysts in multicystic kidneys. MR investigation is helpful in selected patients and may be used as an alternative.
Department of Diagnostic Radiology, University Hospital of Turku, Finland.
S
S
Kajander
T
T
Kallio
A
A
Alanen
M
M
Komu
J
J
Forsström
D000328:Adult; D000368:Aged; D006801:Humans; D007668:Kidney / Q000000981:diagnostic imaging / Q000473:pathology; D052177:Kidney Diseases, Cystic / Q000175:diagnosis / Q000000981:diagnostic imaging; D007676:Kidney Failure, Chronic / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D016030:Kidney Transplantation; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D011446:Prospective Studies; D014463:Ultrasonography