Luo Kai, Yu Anding, Fu Qinglin, Pan Liang, Dou Weiqiang, Zhang Jinggang, Chen Jie
Department of Radiology, The Third Affiliated Hospital of Soochow University, Changzhou, China.
MR Research China, GE Healthcare, Beijing, China.
Quant Imaging Med Surg. 2023 Apr 1;13(4):2441-2450. doi: 10.21037/qims-22-838. Epub 2023 Mar 3.
There were no effective noninvasive methods to diagnose renal ischemia-reperfusion injury (IRI), which is a major clinical problem. The objective of this study was to explore the feasibility of the quantitative susceptibility mapping (QSM) technique in evaluating the dynamic changes in the renal IRI process.
A total of 36 New Zealand rabbits were randomly assigned to the IRI group (n=30) and the sham group (n=6). All rabbits underwent magnetic resonance imaging (MRI) examination, including T2-weighted imaging and QSM before the operation (pre-IRI) and 1, 12, 24, and 48 h after the operation (IRI-1h, IRI-12h, IRI-24h, and IRI-48h, respectively). Regions of interest were manually delineated in the outer medulla. All specimens were stained with hematoxylin and eosin (HE) and glutathione peroxidase 4 (GPX4). The pathological score of renal injury and the average optical density value of GPX4 were calculated. The repeated measurement analysis of variance (ANOVA) and Spearman correlation analysis were used to compare the differences between the susceptibility values and determine the correlation.
In the IRI group, the susceptibility values of the outer medulla at the pre-IRI, IRI-1h, IRI-12h, IRI-24h, and IRI-48h time points were (42.83±7.83)×10, (-5.33±6.28)×10, (6.50±3.94)×10, (12.00±3.74)×10, and (22.00±6.81)×10 ppm, respectively. The susceptibility values significantly differed among the different time points (P<0.001). The susceptibility values had a negative correlation with the scores of cell edema (ρ=-0.61; P=0.002) and the average optical density value of GPX4 (ρ=-0.70; P<0.001). The susceptibility values had a positive correlation with iron content (ρ=0.79; P<0.001), the scores of cell necrosis (ρ=0.71; P<0.001), interstitial inflammation (ρ=0.60; P=0.002), cast (ρ=0.75; P<0.001), and the total pathological score of renal injury (ρ=0.51; P=0.01).
QSM can be used as a noninvasive method to assess the dynamic changes of the outer medulla in the early stage of renal IRI in rabbits.
肾缺血再灌注损伤（IRI）是一个主要的临床问题，目前尚无有效的非侵入性诊断方法。本研究的目的是探讨定量磁化率成像（QSM）技术评估肾IRI过程中动态变化的可行性。
将36只新西兰兔随机分为IRI组（n = 30）和假手术组（n = 6）。所有兔子均接受磁共振成像（MRI）检查，包括术前（IRI前）以及术后1、12、24和48小时（分别为IRI - 1h、IRI - 12h、IRI - 24h和IRI - 48h）的T2加权成像和QSM。在外髓质手动勾勒感兴趣区域。所有标本用苏木精和伊红（HE）以及谷胱甘肽过氧化物酶4（GPX4）染色。计算肾损伤的病理评分和GPX4的平均光密度值。采用重复测量方差分析（ANOVA）和Spearman相关性分析比较磁化率值之间的差异并确定相关性。
在IRI组中，外髓质在IRI前、IRI - 1h、IRI - 12h、IRI - 24h和IRI - 48h时间点的磁化率值分别为（42.83±7.83）×10、（ - 5.33±6.28）×10、（6.50±3.94）×10、（12.00±3.74）×10和（22.00±6.81）×10 ppm。不同时间点的磁化率值有显著差异（P < 0.001）。磁化率值与细胞水肿评分（ρ = - 0.61；P = 0.002）和GPX4的平均光密度值（ρ = - 0.70；P < 0.001）呈负相关。磁化率值与铁含量（ρ = 0.79；P < 0.001）、细胞坏死评分（ρ = 0.71；P < 0.001）、间质炎症（ρ = 0.60；P = 0.002）、管型（ρ = 0.75；P < 0.001）以及肾损伤的总病理评分（ρ = 0.51；P = 0.01）呈正相关。
QSM可作为一种非侵入性方法评估兔肾IRI早期外髓质的动态变化。
