Objectives: To test the feasibility of a single MR-based examination allowing for the comprehensive assessment of renal anatomy, function, and vascular status in candidates for kidney transplantation.
Materials and methods: Twelve healthy potential kidney donors (mean age: 47 +/- 14 [standard deviation] years, 3 men and 9 women) participated in the study, which was approved by the local ethics committee. MR-nephrography was performed using a navigator-gated T1-weighted saturation-recovery sequence (TrueFISP: TR/TE = 621.31 milliseconds/1.27 milliseconds, Flip angle = 70 degrees, TI = 300 milliseconds, BW = 977 Hz/Px, or TurboFLASH: TR/TE = 528 milliseconds/1.15 milliseconds, Flip angle = 8 degrees, TI = 300 milliseconds, BW = 600 Hz/Px). Images were acquired up to 60 minutes after the injection of 4 mL of gadobutrol. The glomerular filtration rate (GFR) was evaluated from the renal clearance of gadobutrol within the extra cellular fluid volume by exponential fitting of time-signal curves measured over the liver. MR-angiography was performed using a T1-weighted 3D-Flash sequence. The overall measuring time was 70 to 80 minutes. For each subject, GFR data were compared with the results of renal scintigraphy with Tc-labeled DTPA from the same day.
Results: Kidney anatomy and vascular status were successfully assessed in all subjects. The results of MR-angiography were in excellent accordance with the surgical findings. MR-nephrography presented a good agreement to the scintigraphy (mean GFR from MR-nephrography = 117 +/- 24 mL/min per 1.73 m; mean GFR from scintigraphy = 116 +/- 26 mL/min per 1.73 m). The Bland-Altman-plot showed a mean difference in measurements pairs of -1 +/- 12 mL/min per 1.73 m. The absolute paired difference ranged between 0 and 22 mL/min per 1.73 m.
Conclusions: The study showed the feasibility of the comprehensive assessment of renal anatomy, function, and vascular morphology, using 1 single MR examination. The proposed protocol may find immediate clinical application in the preoperative assessment of potential kidney donors.