Furukawa A, Murata K, Pak K, Yamasaki M, Kawaguchi N, Inoue H, Tomoyoshi T, Abe H, Sako H, Okino K, Kodama M, Nakane Y, Morita R
Dept. of Radiology, Shiga University of Medical Science, and Omihachiman City Hospital.
Nihon Igaku Hoshasen Gakkai Zasshi. 1996 Oct;56(12):807-12.
The purpose of the study was to evaluate the potential of dynamic Gd-DTPA-enhanced MR imaging in assessing of the function of transplanted kidneys. Dynamic MR imaging was performed using the GRASS pulse sequence in 21 subjects (56 examinations), and in each examination 30 images were obtained after a bolus injection of Gd-DTPA. Imaging findings including signal increase and/or signal drop in cortex, signal drop in medulla, and signal drop in calyces were utilized for the evaluation of renal function. Renal function was also evaluated using the following parameters: Ta, time between the initial observation of signal increase in cortex and signal drop in medulla. Tb, time between the initial observation of signal drop in medulla and in calyces; Tc, Ta + Tb, and Max. C/M, maximum ratio of signal intensity between cortex and medulla among 30 images. In the group of patients with normal graft function (Ccr > or = 60ml/min), all imaging findings were observed. In the group of patients with mild graft dysfunction (30ml/min < or = Ccr < 60ml/min), all imaging findings but signal drop in cortex were observed. The time parameters of Ta, Tb, and Tc were significantly larger, and Max. C/M was significantly smaller than those observed in the group with normal graft function. In the group of patients with severe graft dysfunction (Ccr < 30ml/min), almost none of the findings were observed. The investigation in patients in the postoperative state revealed a close correlation of the imaging findings and the values of parameters with changes in graft function over time. The results indicated the usefulness of the method in semiquantitative evaluation of graft function, including that of patients in postoperative state. This study suggests that dynamic Gd-DTPA-enhanced MR imaging could be a valuable method for the management of transplanted kidneys.
本研究的目的是评估动态钆喷酸葡胺（Gd-DTPA）增强磁共振成像（MR成像）在评估移植肾肾功能方面的潜力。对21名受试者（共进行56次检查）使用梯度回波（GRASS）脉冲序列进行动态MR成像，每次检查在静脉注射Gd-DTPA后获取30幅图像。利用皮质信号增强和/或信号下降、髓质信号下降以及肾盏信号下降等成像表现来评估肾功能。还使用以下参数评估肾功能：Ta，皮质信号开始增强至髓质信号下降之间的时间；Tb, 髓质信号开始下降至肾盏信号下降之间的时间；Tc，Ta + Tb；以及最大皮质/髓质信号强度比（Max. C/M），即30幅图像中皮质与髓质信号强度的最大比值。在移植肾功能正常（肌酐清除率Ccr≥60ml/min）的患者组中，观察到了所有成像表现。在移植肾功能轻度受损（30ml/min≤Ccr＜60ml/min）的患者组中，除皮质信号下降外，观察到了所有成像表现。Ta、Tb和Tc的时间参数显著增大，且Max. C/M显著低于移植肾功能正常组。在移植肾功能严重受损（Ccr＜30ml/min）的患者组中，几乎未观察到任何表现。对术后患者的研究表明，成像表现和参数值与移植肾功能随时间的变化密切相关。结果表明该方法在半定量评估移植肾功能（包括术后患者）方面具有实用性。本研究提示，动态Gd-DTPA增强MR成像可能是一种用于移植肾管理的有价值方法。
