Department of Computing Science, University of Alberta, Canada.
Ultrasonics. 2019 Jul;96:24-33. doi: 10.1016/j.ultras.2019.03.014. Epub 2019 Mar 23.
A Fully Convolutional Network (FCN) based deep architecture called Dual Path U-Net (DPU-Net) is proposed for automatic segmentation of the lumen and media-adventitia in IntraVascular UltraSound (IVUS) frames, which is crucial for diagnosis of many cardiovascular diseases and also for facilitating 3D reconstructions of human arteries. One of the most prevalent problems in medical image analysis is the lack of training data. To overcome this limitation, we propose a twofold solution. First, we introduce a deep architecture that is able to learn using a small number of training images and still achieves a high degree of generalization ability. Second, we strengthen the proposed DPU-Net by having a real-time augmentor control the image augmentation process. Our real-time augmentor contains specially-designed operations that simulate three types of IVUS artifacts and integrate them into the training images. We exhaustively assessed our twofold contribution over Balocco's standard publicly available IVUS 20 MHz and 40 MHz B-mode dataset, which contain 109 training image, 326 test images and 19 training images, 59 test images, respectively. Models are trained from scratch with the training images provided and evaluated with two commonly used metrics in the IVUS segmentation literature, namely Jaccard Measure (JM) and Hausdorff Distance (HD). Experimental results show that DPU-Net achieves 0.87 JM, 0.82 mm HD and 0.86 JM, 1.07 mm HD over 40 MHz dataset for segmenting the lumen and the media, respectively. Also, DPU-Net achieves 0.90 JM, 0.25 mm HD and 0.92 JM, 0.30 mm HD over 20 MHz images for segmenting the lumen and the media, respectively. In addition, DPU-Net outperforms existing methods by 8-15% in terms of HD distance. DPU-Net also shows a strong generalization property for predicting images in the test sets that contain a significant amount of major artifacts such as bifurcations, shadows, and side branches that are not common in the training set. Furthermore, DPU-Net runs within 0.03 s to segment each frame with a single modern GPU (Nvidia GTX 1080). The proposed work leverages modern deep learning-based method for segmentation of lumen and the media vessel walls in both 20 MHz and 40 MHz IVUS B-mode images and achieves state-of-the-art results without any manual intervention. The code is available online at https://github.com/Kulbear/IVUS-Ultrasonic.
提出了一种基于全卷积网络(FCN)的深度学习架构,称为双路径 U-Net(DPU-Net),用于自动分割血管内超声(IVUS)帧中的管腔和血管壁中层-外膜,这对于许多心血管疾病的诊断以及促进人类动脉的 3D 重建至关重要。医学图像分析中最常见的问题之一是缺乏训练数据。为了克服这一限制,我们提出了双重解决方案。首先,我们引入了一种能够使用少量训练图像进行学习并且仍然具有高度泛化能力的深度架构。其次,我们通过实时增强器控制图像增强过程来增强所提出的 DPU-Net。我们的实时增强器包含专门设计的操作,可模拟三种类型的 IVUS 伪影,并将其集成到训练图像中。我们在 Balocco 的标准公开可用的 IVUS 20MHz 和 40MHz B 模式数据集上对我们的双重贡献进行了详尽的评估,该数据集分别包含 109 个训练图像、326 个测试图像和 19 个训练图像、59 个测试图像。模型从零开始使用提供的训练图像进行训练,并使用 IVUS 分割文献中常用的两种度量标准进行评估,即 Jaccard 度量(JM)和 Hausdorff 距离(HD)。实验结果表明,DPU-Net 在分割管腔和中层时,在 40MHz 数据集上分别达到 0.87JM、0.82mmHD 和 0.86JM、1.07mmHD。此外,DPU-Net 在分割管腔和中层时,在 20MHz 图像上分别达到 0.90JM、0.25mmHD 和 0.92JM、0.30mmHD。此外,DPU-Net 在 HD 距离方面的性能优于现有方法 8-15%。DPU-Net 还表现出很强的泛化能力,能够预测测试集中包含大量主要伪影(例如分支、阴影和侧支)的图像,这些伪影在训练集中并不常见。此外,DPU-Net 在单个现代 GPU(Nvidia GTX 1080)上运行时,每帧的分割时间不到 0.03s。所提出的工作利用基于现代深度学习的方法来分割 20MHz 和 40MHz IVUS B 模式图像中的管腔和血管壁中层,并在无需任何人工干预的情况下达到最先进的结果。代码可在 https://github.com/Kulbear/IVUS-Ultrasonic 上获得。