Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg Eppendorf, Hamburg, Germany.
Department of Radiology, Charité - Universitätsmedizin Berlin, Campus Mitte, Campus Mitte, Humboldt-Universität zu Berlin, Freie Universität Berlin, Berlin Institute of Health (BIH), BIH Biomedical Innovation Academy, Berlin, Germany.
Transl Stroke Res. 2021 Dec;12(6):958-967. doi: 10.1007/s12975-021-00891-8. Epub 2021 Feb 6.
We hypothesized that imaging-only-based machine learning algorithms can analyze non-enhanced CT scans of patients with acute intracerebral hemorrhage (ICH). This retrospective multicenter cohort study analyzed 520 non-enhanced CT scans and clinical data of patients with acute spontaneous ICH. Clinical outcome at hospital discharge was dichotomized into good outcome and poor outcome using different modified Rankin Scale (mRS) cut-off values. Predictive performance of a random forest machine learning approach based on filter- and texture-derived high-end image features was evaluated for differentiation of functional outcome at mRS 2, 3, and 4. Prediction of survival (mRS ≤ 5) was compared to results of the ICH Score. All models were tuned, validated, and tested in a nested 5-fold cross-validation approach. Receiver-operating-characteristic area under the curve (ROC AUC) of the machine learning classifier using image features only was 0.80 (95% CI [0.77; 0.82]) for predicting mRS ≤ 2, 0.80 (95% CI [0.78; 0.81]) for mRS ≤ 3, and 0.79 (95% CI [0.77; 0.80]) for mRS ≤ 4. Trained on survival prediction (mRS ≤ 5), the classifier reached an AUC of 0.80 (95% CI [0.78; 0.82]) which was equivalent to results of the ICH Score. If combined, the integrated model showed a significantly higher AUC of 0.84 (95% CI [0.83; 0.86], P value <0.05). Accordingly, sensitivities were significantly higher at Youden Index maximum cut-offs (77% vs. 74% sensitivity at 76% specificity, P value <0.05). Machine learning-based evaluation of quantitative high-end image features provided the same discriminatory power in predicting functional outcome as multidimensional clinical scoring systems. The integration of conventional scores and image features had synergistic effects with a statistically significant increase in AUC.
我们假设基于影像学的机器学习算法可以分析急性脑出血(ICH)患者的非增强 CT 扫描。这项回顾性多中心队列研究分析了 520 例急性自发性 ICH 患者的非增强 CT 扫描和临床数据。使用不同的改良 Rankin 量表(mRS)截断值,将出院时的临床结局分为良好结局和不良结局。基于随机森林机器学习方法的预测性能,基于滤波和纹理衍生的高端图像特征,对 mRS 2、3 和 4 的功能结局进行区分。将生存(mRS ≤ 5)的预测与 ICH 评分的结果进行比较。所有模型均采用嵌套 5 折交叉验证方法进行调整、验证和测试。仅使用图像特征的机器学习分类器的受试者工作特征曲线下面积(ROC AUC)为 0.80(95%CI[0.77;0.82]),用于预测 mRS ≤ 2,0.80(95%CI[0.78;0.81]),用于预测 mRS ≤ 3,0.79(95%CI[0.77;0.80]),用于预测 mRS ≤ 4。针对生存预测(mRS ≤ 5)进行训练后,分类器达到了 0.80(95%CI[0.78;0.82])的 AUC,与 ICH 评分的结果相当。如果结合使用,综合模型的 AUC 显著更高,为 0.84(95%CI[0.83;0.86],P 值<0.05)。因此,在约登指数最大截断值时,灵敏度显著更高(77%比 74%,特异性为 76%,P 值<0.05)。基于机器学习的定量高端图像特征评估在预测功能结局方面具有与多维临床评分系统相同的区分能力。常规评分与图像特征的整合具有协同效应,AUC 有统计学显著增加。