Objectives: The automatic detection of acute ischemic stroke (AIS) and hemorrhagic infarction (HI) based on deep learning could avoid missed diagnosis. The fully supervised learning requires the amount of time and the expertise to manually outline lesions, which limits its applicability. The weakly supervised learning has the potential to reduce the labeling workload. The purpose of this study was to evaluate a weakly supervised method in detection of AIS and HI location using DWI.
Methods: We proposed to adopt weakly supervised learning to spatially-locate AIS lesions by residual neural network (ResNet) and visual geometry group (VGG) network. On an AIS dataset, the area under the receiver operating characteristic (ROC) curve (AUC), sensitivity and precision were calculated. Next, ResNet, which presented superior performance on the AIS dataset, was further applied to an HI dataset.
Results: In the AIS dataset, the AUCs of ResNet and VGG on identifying image slices with AIS were 0.97 and 0.94, respectively. On spatially-locating the AIS lesions, ResNet provided higher sensitivity and a lower missed diagnosis rate than VGG, especially for pontine AIS lesions. In the HI dataset, the sensitivity of ResNet was 87.73% for AIS detection, and 86.20% for HI detection, respectively.
Conclusions: Weakly supervised learning can effectively detect the location of AIS and HI lesions in DWI, which is of paramount importance in avoiding misdiagnosis in clinical scenario.