Assessment of intrarenal oxygenation in renal donor with blood oxygenation level-dependent magnetic resonance imaging

摘要

Objective To examine change of the apparent relaxation rate R2* values in living kidney donors after uninephrectomy using blood oxygenation level-dependent magnetic resonance imaging. Methods Between July 2011 and January 2012, 45 kidney donors were enrolled into this study. Blood oxygenation level-dependent magnetic resonance imaging scanning was performed before surgery, 3 and 7 days postoperatively. Participants were followed up for 1 year. Results The R2* values in medulla (mR2*) were significantly greater than that of cortex (cR2*), both in resected kidney and remaining one. cR2* values of the remaining kidney was 17.52 ± 1.36 s-1 and then decrease significantly by 8.97% to 15.95 ± 1.14 s-1 at 3 days (P .001) and by 7.82% to 16.15 ± of 1.05 s-1 at 7 days. No significant modification occurred in mR2* after surgery. Multivariate regression analysis showed that the decrease in cR2* values of the remaining kidney was positively associated with sex (r = 0.418), body surface area (r = 0.307), and preoperative cR2* values (r = 0.659). Comparing with glomerular filtration rate at 7 days, a further increment in the glomerular filtration rate was noted at 1 year in patients with cR2* values decrease of ≥10% at 1 week (62.63 ± 11.69 vs 56.97 ± 7.51 mL/min/1.73 m2, P =.02) but not in the other patients (66.43 ± 10.89 vs 62.78 ± 13.74, P =.064). Conclusion Kidney donation will induce early, profound oxygenation modification within the renal cortex of the remaining kidney. Donors with cR2* value decrease of ≥10% at 1 week have a more favorable renal function compensation at 1 year.