• Original Article •
BOLD MRI of rat kidney changes during acute unilateral ureteral obstruction at 3.0 T
DOI:10.3969/j.issn.1674-8034.2011.06.010.
| [Abstract] Objective: To evaluate the renal oxygenation changes during acute unilateral ureteral obstruction in rats using blood oxygen level-dependent MR imaging (BOLD MRI) in 3.0 T MR.Materials and Methods: Sixteen healthy SD rats, 3 rats died because of anesthesia, 13 rats were performed kidney T2WI and coronal BOLD imaging respectively before UUO, 1 hour after UUO and 1 hour after release of UUO. Observed the signal and anatomical structure changes among the different groups of renal cortex and medulla, compared the SNR of renal parenchyma among three groups. BOLD images were reconstructed on 4.4 workstation, R2* values were determined in the cortex and medulla of the obstructed and the contralateral nonobstructed kidneys, then comparative analysis of R2* values of renal cortex and medulla among different groups. Compared with the rate of R2* values changes between the mild obstruction and severe obstruction; Analyze the relationship of relief group and no relief group with obstructions and R2* changes.Results: The SNR between left and right renal were the same, and renal anatomy was showed clearly before UUO. After UUO the SNR of 13 rats affected side renal was significantly higher than before, the boundaries of cortex and medulla show blurry, and the pelviectasis in varying degrees. After release of UUO, the SNR higher than the obstruction former group, lower than the obstruction group, the boundaries got clearly, and the renal pelvis recovery in varying degrees. Before UUO, the R2* values of medulla was significantly higher than that of renal cortex, but during the UUO was associated with a decreased R2* in medulla, and after release of obstruction the medulla R2* were increased slowly. The R2* showed no statistical difference in the cortex and nonobstructed kidneys among three groups. The rates of R2* change in mild obstruction slightly less than in severe obstruction. The obstruction and the R2* changes in relief group were lower than those in no relief group.Conclusions: 3.0 T BOLD MRI provides a useful tool in UUO which is associated with altered renal oxygen consumption. |
| [Keywords] Magnetic resonance imaging；Renal；Acute unilateral ureteral obstruction；Blood oxygen level-dependent |
XING Jin-zi Department of Radiology, the First Affiliated Hospital of Dalian Medical University, Dalian 116011, China
LIU Ai-lian* Department of Radiology, the First Affiliated Hospital of Dalian Medical University, Dalian 116011, China
SONG Qing-wei Department of Radiology, the First Affiliated Hospital of Dalian Medical University, Dalian 116011, China
YANG Chun-yang Dalian Medical University, Dalian 116011, China
*Correspondence to: Liu AL, E-mail: cjr.liuailian@vip.163.com
Conflicts of interest None.
| Received 2011-07-02 |
| Accepted 2011-10-20 |
| DOI: 10.3969/j.issn.1674-8034.2011.06.010 |
| DOI:10.3969/j.issn.1674-8034.2011.06.010. |
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