Department of Computer Science, University College London, London, United Kingdom.
Computational Imaging, Centrum Wiskunde and Informatica (CWI), Amsterdam, Netherlands.
Magn Reson Med. 2019 Feb;81(2):1143-1156. doi: 10.1002/mrm.27480. Epub 2018 Sep 8.
Real-time assessment of ventricular volumes requires high acceleration factors. Residual convolutional neural networks (CNN) have shown potential for removing artifacts caused by data undersampling. In this study, we investigated the ability of CNNs to reconstruct highly accelerated radial real-time data in patients with congenital heart disease (CHD).
A 3D (2D plus time) CNN architecture was developed and trained using synthetic training data created from previously acquired breath hold cine images from 250 CHD patients. The trained CNN was then used to reconstruct actual real-time, tiny golden angle (tGA) radial SSFP data (13 × undersampled) acquired in 10 new patients with CHD. The same real-time data was also reconstructed with compressed sensing (CS) to compare image quality and reconstruction time. Ventricular volume measurements made using both the CNN and CS reconstructed images were compared to reference standard breath hold data.
It was feasible to train a CNN to remove artifact from highly undersampled radial real-time data. The overall reconstruction time with the CNN (including creation of aliased images) was shown to be >5 × faster than the CS reconstruction. In addition, the image quality and accuracy of biventricular volumes measured from the CNN reconstructed images were superior to the CS reconstructions.
This article has demonstrated the potential for the use of a CNN for reconstruction of real-time radial data within the clinical setting. Clinical measures of ventricular volumes using real-time data with CNN reconstruction are not statistically significantly different from gold-standard, cardiac-gated, breath-hold techniques.
实时评估心室容积需要高加速因子。残差卷积神经网络(CNN)已显示出去除因数据欠采样而产生的伪影的潜力。在这项研究中,我们研究了 CNN 在重建先天性心脏病(CHD)患者高加速径向实时数据方面的能力。
使用从 250 例 CHD 患者先前采集的屏气电影图像中创建的合成训练数据,开发并训练了一个 3D(2D 加时间)CNN 架构。然后,使用该训练好的 CNN 重建实际的实时、微小黄金角(tGA)径向 SSFP 数据(13 倍欠采样),这些数据是在 10 例新的 CHD 患者中采集的。同样的实时数据也使用压缩感知(CS)进行重建,以比较图像质量和重建时间。使用 CNN 和 CS 重建图像进行的心室容积测量与参考标准屏气数据进行了比较。
可以训练 CNN 从高度欠采样的径向实时数据中去除伪影。CNN 的整体重建时间(包括创建混淆图像)比 CS 重建快 5 倍以上。此外,从 CNN 重建图像测量的双心室容积的图像质量和准确性优于 CS 重建。
本文证明了在临床环境中使用 CNN 进行实时径向数据重建的潜力。使用 CNN 重建实时数据进行的临床心室容积测量与金标准、心脏门控、屏气技术没有统计学上的显著差异。