Highly accelerated MR parametric mapping by undersampling the k-space and reducing the contrast number simultaneously with deep learning

TL;DR

This paper introduces RG-Net, a deep learning framework that accelerates MR parametric mapping by undersampling k-space data and reducing contrast numbers simultaneously, achieving high-quality results at high acceleration rates.

Contribution

The novel RG-Net combines reconstruction and generative modules to significantly speed up MR parametric mapping while maintaining accuracy, outperforming existing methods.

Findings

RG-Net achieves a high acceleration rate of 17.

It produces high-quality T1ρ maps in knee and brain imaging.

It outperforms competing methods in T1ρ value analysis.

Abstract

Purpose: To propose a novel deep learning-based method called RG-Net (reconstruction and generation network) for highly accelerated MR parametric mapping by undersampling k-space and reducing the acquired contrast number simultaneously. Methods: The proposed framework consists of a reconstruction module and a generative module. The reconstruction module reconstructs MR images from the acquired few undersampled k-space data with the help of a data prior. The generative module then synthesizes the remaining multi-contrast images from the reconstructed images, where the exponential model is implicitly incorporated into the image generation through the supervision of fully sampled labels. The RG-Net was evaluated on the T1\r{ho} mapping data of knee and brain at different acceleration rates. Regional T1\r{ho} analysis for cartilage and the brain was performed to access the performance of RG-Net. Results: RG-Net yields a high-quality T1\r{ho} map at a high acceleration rate of 17. Compared with the competing methods that only undersample k-space, our framework achieves better performance in T1\r{ho} value analysis. Our method also improves quality of T1\r{ho} maps on patient with glioma. Conclusion: The proposed RG-Net that adopted a new strategy by undersampling k-space and reducing the contrast number simultaneously for fast MR parametric mapping, can achieve a high acceleration rate while maintaining good reconstruction quality. The generative module of our framework can also be used as an insert module in other fast MR parametric mapping methods. Keywords: Deep learning, convolutional neural network, fast MR parametric mapping