Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, People's Republic of China.
Institute of Molecular and Function Imaging, Jinan University, Guangzhou, People's Republic of China.
Abdom Radiol (NY). 2018 Mar;43(3):655-662. doi: 10.1007/s00261-017-1247-8.
Contrast-induced acute kidney injury is a prevalent cause of renal failure, and the noninvasive tools to monitor its progress are lacking. We applied intravoxel incoherent motion (IVIM) DWI to measure the progressive changes in kidney diffusion and perfusion of CI-AKI.
Twenty-four rats received Iopromide (370 mg/ml, 1600 mg iodine/kg) to induce CI-AKI. IVIM DWI was performed on rats (n = 6) at 24 h prior to and 12, 24, 48, 72, and 96 h after the injection using a 3.0 T MRI scanner. The progressive changes in the diffusion (D) and perfusion parameters (D* and f) were studied in the cortex (CO), outer medulla (OM), and inner medulla (IM). For the histology group (n = 18), three rats were sacrificed at each time point.
In the CO, D reduced progressively from 24 to 48 h (P < 0.001) and increased starting from 72 h (P < 0.001). However, D decreased until to 72 h in the medulla (P < 0.001) and increased starting from 96 h (P < 0.001). D* decreased to the bottom at 24 h in the cortex and medulla (P = 0.037) and started to recover at 48 h (P = 0.007). f decreased in the cortex and medulla in an early stage (12 h) (P = 0.035) of CI-AKI and then ascended in the later stage (72 h) (P = 0.017). The H & E staining showed different degrees of serial pathological change including cloudy swelling, atrophy, even necrosis, and interstitial vasodilation of tubule epithelial cells and glomerulus cells.
Our study demonstrates the feasibility of using IVIM DWI to monitor the progress of CI-AKI, implying that IVIM DWI is a useful biomarker in the staging of CI-AKI.
对比剂诱导的急性肾损伤是肾衰竭的一个常见原因，目前缺乏监测其进展的非侵入性工具。我们应用体素内不相干运动（IVIM）DWI 来测量 CI-AKI 患者肾脏扩散和灌注的渐进性变化。
24 只大鼠接受碘普罗胺（370mg/ml，1600mg 碘/kg）注射以诱导 CI-AKI。在注射前 24 小时以及注射后 12、24、48、72 和 96 小时，使用 3.0T MRI 扫描仪对 6 只大鼠进行 IVIM DWI。研究了皮质（CO）、外髓（OM）和内髓（IM）中扩散（D）和灌注参数（D*和 f）的渐进性变化。对于组织学组（n=18），每个时间点处死 3 只大鼠。
在 CO 中，D 值从 24 小时到 48 小时逐渐降低（P<0.001），并从 72 小时开始增加（P<0.001）。然而，D 值在内髓中一直降低到 72 小时（P<0.001），并从 96 小时开始增加（P<0.001）。D*在皮质和髓质中在 24 小时达到最低点（P=0.037），并在 48 小时开始恢复（P=0.007）。f 在 CI-AKI 的早期（12 小时）在皮质和髓质中降低（P=0.035），然后在晚期（72 小时）上升（P=0.017）。H&E 染色显示出不同程度的连续病理变化，包括肾小管上皮细胞和肾小球细胞的混浊肿胀、萎缩、甚至坏死和间质血管扩张。
本研究表明，使用 IVIM DWI 监测 CI-AKI 进展是可行的，这意味着 IVIM DWI 是评估 CI-AKI 分期的有用生物标志物。
