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Dynamic Contrast-Enhanced MR Imaging in the Evaluation of Renal Transplant Preliminary Observations<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
冯逢 孟薇 金阳 杨文领 金征宇
中国医学科学院 中国协和医科大学
北京协和医院放射科, 北京100730
Feng Feng, Wei Meng, Yang Jin, Wenling Yang, Zhengyu Jin
Department of radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College，Beijing 100730, China
ABSTRACT
Objective: To evaluate the role of the dynamic gadolinium-DTPA (Gd-DTPA) enhanced magnetic resonance imaging in assessing the function of the renal allografts.
Methods: Contrast enhanced dynamic MR imaging (FFE sequence, TR/TE=40ms/5ms, flip angle=25°) was performed by using a 1.5-T superconductive magnet system in 11 renal allografts. Among them, there were 6 normal renal allografts, 3 patients with acute rejection, 1 patient with chronic rejection, and 1 patient with regional graft infarction. The time-signal intensity (SI) curves were plotted by applying the ROI in the upper, middle and lower parts of the cortex and the medulla. Mean signal intensity value at the cortex and the medulla of each allograft were obtained. Statistics analysis was made with the SPSS software. The comparison of the peak SI value between the normal renal allografts group and the AR group was made by using Mann-Whitney U test.
Results: In normal renal allografts, time-SI curves showed a rapid increase and slow decay, with a definite peak in cortical SI curves. The medullary curves did not show a definite peak, it slowly reached a steady state and caught up with the cortical curve. The acute rejection episodes showed a blunted upraise and delayed peak of cortical curve and a low-amplitude peak SI of cortex, which had a statistical significance with that of the normal group. The medullary SI curve failed to catch up with the cortical curve.
Conclusion: Dynamic contrast-enhanced MRI was suggested to permit a comprehensive assessment of renal transplants without inducing nephrotoxicity. Further investigation on the MRR to assess the functional state of the renal allograft with various causes of dysfunction is needed.
Key words: Magnetic Resonance Imaging; Renal Allograf; Gadolium-DTPA |
