Intensity non-uniformity correction in MR imaging using residual cycle generative adversarial network

• Authors: Xianjin Dai, Emory University; Yang Lei, Emory University; Yingzi Liu, Emory University; Tonghe Wang, Emory University; Lei Ren, Duke University; Walter J Curran, Emory University; Pretesh Patel, Emory University; Tian Liu, Emory University; Xiaofeng Yang, Emory University
• Journal Title: PHYSICS IN MEDICINE AND BIOLOGY
• Volume: Volume 65, Number 21
• Publisher: IOP PUBLISHING LTD | 2020-11-07, Pages 215025-215025
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1088/1361-6560/abb31f
• Subjects: Health Sciences, Oncology; Biology, Radiation
• Keywords: Science & Technology; Technology; Life Sciences & Biomedicine; Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging; Engineering; magnetic resonance imaging (MRI); bias field; intensity non-uniformity; deep learning; generative adversarial network (GAN); BIAS FIELD ESTIMATION; RETROSPECTIVE CORRECTION; FAT-SUPPRESSION; ABDOMINAL MRI; INHOMOGENEITY; SEGMENTATION; DENSITY; TUMORS; N3

Abstract

Correcting or reducing the effects of voxel intensity non-uniformity (INU) within a given tissue type is a crucial issue for quantitative magnetic resonance (MR) image analysis in daily clinical practice. Although having no severe impact on visual diagnosis, the INU can highly degrade the performance of automatic quantitative analysis such as segmentation, registration, feature extraction and radiomics. In this study, we present an advanced deep learning based INU correction algorithm called residual cycle generative adversarial network (res-cycle GAN), which integrates the residual block concept into a cycle-consistent GAN (cycle-GAN). In cycle-GAN, an inverse transformation was implemented between the INU uncorrected and corrected magnetic resonance imaging (MRI) images to constrain the model through forcing the calculation of both an INU corrected MRI and a synthetic corrected MRI. A fully convolution neural network integrating residual blocks was applied in the generator of cycle-GAN to enhance end-to-end raw MRI to INU corrected MRI transformation. A cohort of 55 abdominal patients with T1-weighted MR INU images and their corrections with a clinically established and commonly used method, namely, N4ITK were used as a pair to evaluate the proposed res-cycle GAN based INU correction algorithm. Quantitatively comparisons of normalized mean absolute error (NMAE), peak signal-to-noise ratio (PSNR), normalized cross-correlation (NCC) indices, and spatial non-uniformity (SNU) were made among the proposed method and other approaches. Our res-cycle GAN based method achieved an NMAE of 0.011 0.002, a PSNR of 28.0 1.9 dB, an NCC of 0.970 0.017, and a SNU of 0.298 0.085. Our proposed method has significant improvements (p < 0.05) in NMAE, PSNR, NCC and SNU over other algorithms including conventional GAN and U-net. Once the model is well trained, our approach can automatically generate the corrected MR images in a few minutes, eliminating the need for manual setting of parameters.