Center for Pervasive Communications and Computing, University of California, Irvine, Irvine, USA.
Edwards Lifesciences Center for Advanced Cardiovascular Technology, University of California, Irvine, Irvine, USA.
J Cardiovasc Magn Reson. 2020 Nov 30;22(1):80. doi: 10.1186/s12968-020-00678-0.
For the growing patient population with congenital heart disease (CHD), improving clinical workflow, accuracy of diagnosis, and efficiency of analyses are considered unmet clinical needs. Cardiovascular magnetic resonance (CMR) imaging offers non-invasive and non-ionizing assessment of CHD patients. However, although CMR data facilitates reliable analysis of cardiac function and anatomy, clinical workflow mostly relies on manual analysis of CMR images, which is time consuming. Thus, an automated and accurate segmentation platform exclusively dedicated to pediatric CMR images can significantly improve the clinical workflow, as the present work aims to establish.
Training artificial intelligence (AI) algorithms for CMR analysis requires large annotated datasets, which are not readily available for pediatric subjects and particularly in CHD patients. To mitigate this issue, we devised a novel method that uses a generative adversarial network (GAN) to synthetically augment the training dataset via generating synthetic CMR images and their corresponding chamber segmentations. In addition, we trained and validated a deep fully convolutional network (FCN) on a dataset, consisting of [Formula: see text] pediatric subjects with complex CHD, which we made publicly available. Dice metric, Jaccard index and Hausdorff distance as well as clinically-relevant volumetric indices are reported to assess and compare our platform with other algorithms including U-Net and cvi42, which is used in clinics.
For congenital CMR dataset, our FCN model yields an average Dice metric of [Formula: see text] and [Formula: see text] for LV at end-diastole and end-systole, respectively, and [Formula: see text] and [Formula: see text] for RV at end-diastole and end-systole, respectively. Using the same dataset, the cvi42, resulted in [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] for LV and RV at end-diastole and end-systole, and the U-Net architecture resulted in [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] for LV and RV at end-diastole and end-systole, respectively.
The chambers' segmentation results from our fully-automated method showed strong agreement with manual segmentation and no significant statistical difference was found by two independent statistical analyses. Whereas cvi42 and U-Net segmentation results failed to pass the t-test. Relying on these outcomes, it can be inferred that by taking advantage of GANs, our method is clinically relevant and can be used for pediatric and congenital CMR segmentation and analysis.
对于患有先天性心脏病(CHD)的患者群体不断增长,提高临床工作流程的效率、诊断的准确性以及分析的效率被认为是尚未满足的临床需求。心血管磁共振(CMR)成像可提供非侵入性和非电离性的 CHD 患者评估。然而,尽管 CMR 数据有利于心脏功能和解剖结构的可靠分析,但临床工作流程主要依赖于 CMR 图像的手动分析,这既耗时又费力。因此,专门为儿科 CMR 图像设计的自动化且准确的分割平台可以显著改善临床工作流程,这也是本工作的目标。
用于 CMR 分析的人工智能(AI)算法的培训需要大型标注数据集,但这些数据集不适用于儿科患者,特别是 CHD 患者。为了解决这个问题,我们设计了一种新方法,该方法使用生成对抗网络(GAN)通过生成合成 CMR 图像及其对应的腔室分割来合成增强训练数据集。此外,我们在一个包含[Formula: see text]例患有复杂 CHD 的儿科患者的数据集上训练和验证了一个深度全卷积网络(FCN),并将其公开提供。我们使用 Dice 度量、Jaccard 指数和 Hausdorff 距离以及临床相关的体积指数来评估和比较我们的平台与包括 U-Net 和 cvi42 在内的其他算法,cvi42 用于临床。
对于先天性 CMR 数据集,我们的 FCN 模型的平均 Dice 度量分别为 LV 在舒张末期和收缩末期的[Formula: see text]和[Formula: see text],以及 RV 在舒张末期和收缩末期的[Formula: see text]和[Formula: see text]。使用相同的数据集,cvi42 得到的结果分别为 LV 和 RV 在舒张末期和收缩末期的[Formula: see text]、[Formula: see text]、[Formula: see text]和[Formula: see text],而 U-Net 架构得到的结果分别为 LV 和 RV 在舒张末期和收缩末期的[Formula: see text]、[Formula: see text]、[Formula: see text]和[Formula: see text]。
我们的全自动方法的腔室分割结果与手动分割具有很强的一致性,并且通过两种独立的统计分析都没有发现显著的统计学差异。而 cvi42 和 U-Net 的分割结果未能通过 t 检验。基于这些结果,可以推断出,通过利用 GANs,我们的方法具有临床相关性,可用于儿科和先天性 CMR 分割和分析。