METHODS: Twenty domestic pigs with RAS were scanned with CT and BOLD MRI before and 4 weeks after PTRA. Stenotic (STK) and contralateral (CLK) kidney volume, blood flow (RBF), and glomerular filtration rate (GFR) were determined, and BOLD-MRI R2 * maps were generated before and after administration of furosemide, a tubular reabsorption inhibitor. Radiomics features were extracted from pre-PTRA BOLD maps and Robust features were determined by Intraclass correlation coefficients (ICC). Prognostic models were developed to predict post-PTRA renal function based on the baseline functional and BOLD-radiomics features, using Lasso-regression for training, and testing with resampling.
RESULTS: Twenty-six radiomics features passed the robustness test. STK oxygenation distribution pattern did not respond to furosemide, whereas in the CLK radiomics features sensitive to oxygenation heterogeneity declined. Radiomics-based model predictions of post-PTRA GFR (r = 0.58, p = 0.007) and RBF (r = 0.68; p = 0.001) correlated with actual measurements with sensitivity and specificity of 92% and 67%, respectively. Models were unsuccessful in predicting post-PTRA systemic measures of renal function.
CONCLUSIONS: Several radiomics features are sensitive to cortical oxygenation patterns and permit estimation of post-PTRA renal function, thereby distinguishing subjects likely to respond to PTRA and stenting.
方法:在PTRA之前和之后4周用CT和BOLDMRI扫描了20头RAS的家猪。狭窄(STK)和对侧(CLK)肾脏体积,血流量(RBF),测定肾小球滤过率(GFR),和BOLD-MRIR2*图在施用呋塞米之前和之后生成,肾小管重吸收抑制剂.从PTRA之前的BOLD图中提取影像组学特征,并通过组内相关系数(ICC)确定稳健特征。基于基线功能和BOLD-影像组学特征,开发了预测PTRA后肾功能的预后模型。使用Lasso回归进行训练,并通过重新采样进行测试。
结果:二十六个影像组学特征通过了稳健性测试。STK氧合分布模式对呋塞米无反应,而在CLK影像组学中,对氧合异质性敏感的特征下降了。基于影像组学的PTRA后GFR(r=0.58,p=0.007)和RBF(r=0.68;p=0.001)的模型预测与实际测量相关,灵敏度和特异性分别为92%和67%,分别。模型无法成功预测PTRA后肾功能的全身测量。
结论:一些影像组学特征对皮质氧合模式敏感,并允许评估PTRA后的肾功能,从而区分可能对PTRA和支架术有反应的受试者。