Dai Hongyan, Zhao Chun, Xiong Yuxin, He Qian, Su Wei, Li Jianbo, Yang Ying, Lin Ruyun, Xiang Shutian, Shao Juwei
Department of Radiology, The Affiliated Hospital of Yunnan University, NO.176 Qingnian Road, Kunming, 650021, Yunnan, China.
Department of Endocrinology and Metabolism, The Affiliated Hospital of Yunnan University, Kunming, Yunnan, China.
Insights Imaging. 2022 Jun 29;13(1):110. doi: 10.1186/s13244-022-01249-w.
To assess the potential of intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) in monitoring renal changes in a diabetic nephropathy (DN) rat model with acute kidney injury (CI-AKI) induced by iso-osmotic contrast media (IOCM) and low-osmotic contrast media (LOCM).
A diabetic nephropathy rat model was established, and the animals were randomly split into the LOCM group and IOCM group (n = 13 per group), with iopamidol and iodixanol injection, respectively (4 g iodine/kg). MRI including IVIM and DKI was performed 24 h before contrast medium injections (baseline) and 1, 24, 48, and 72 h after injections. Changes in pure molecular diffusion (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), mean diffusion (MD), mean kurtosis (MK), serum creatinine (SCr) and urea nitrogen (BUN), histopathology alterations, and α-smooth muscle actin (α-SMA) expression were assessed. Inter-observer agreement was evaluated using the intraclass correlation coefficient (ICC).
Compared against baseline levels, significant decreases in D, D*, and f were observed in all anatomical kidney compartments after contrast injection (p < 0.05). MD in the cortex (CO) and outer medullary (OM) gradually decreased, and MK in OM gradually increased 24-72 h after injection. D, D*, f, and MD were negatively correlated with the histopathologic findings and α-smooth muscle actin (α-SMA) expression in all anatomical kidney compartments. Inter-observer reproducibility was generally good (ICCs ranging from 0.776 to 0.979).
IVIM and DKI provided noninvasive imaging parameters, which might offer effective detection of CI-AKI in DN.
评估体素内不相干运动（IVIM）和扩散峰度成像（DKI）在监测由等渗造影剂（IOCM）和低渗造影剂（LOCM）诱导的急性肾损伤（CI-AKI）糖尿病肾病（DN）大鼠模型肾脏变化中的潜力。
建立糖尿病肾病大鼠模型，将动物随机分为LOCM组和IOCM组（每组n = 13），分别注射碘帕醇和碘克沙醇（4 g碘/kg）。在注射造影剂前24小时（基线）以及注射后1、24、48和72小时进行包括IVIM和DKI的MRI检查。评估纯分子扩散（D）、伪扩散系数（D*）、灌注分数（f）、平均扩散（MD）、平均峰度（MK）、血清肌酐（SCr）和尿素氮（BUN）的变化、组织病理学改变以及α-平滑肌肌动蛋白（α-SMA）表达。使用组内相关系数（ICC）评估观察者间的一致性。
与基线水平相比，注射造影剂后所有肾脏解剖区域的D、D和f均显著降低（p < 0.05）。皮质（CO）和外髓质（OM）的MD逐渐降低，注射后24 - 72小时OM中的MK逐渐增加。所有肾脏解剖区域的D、D、f和MD与组织病理学结果及α-平滑肌肌动蛋白（α-SMA）表达呈负相关。观察者间的可重复性总体良好（ICC范围为0.776至0.979）。
IVIM和DKI提供了非侵入性成像参数，可能对DN中的CI-AKI进行有效检测。
