Bing-Fong Lin¹, Fei Hon¹, Po-Yi Tsai^2,3, and Chia-Feng Lu^1
1Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan, Taipei, Taiwan, ²Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei, Taiwan, Taipei, Taiwan, ³School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, Taipei, Taiwan

Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) provided promising results to facilitate the language recovery in stroke patients with non-fluent aphasia ¹. The contralesional inhibitory LF-rTMS treatment can induce the functional reorganization within language networks and recovery of language function in chronic aphasic stroke ^{2, 3}. This study evaluated the right microstructural integrity of the arcuate fasciculus before the intervention and its association with the language improvement after the LF-rTMS treatment.

Wataru Uchida¹, Koji Kamagata¹, Christina Andica¹, Yuya Saito¹, Kaito Takabayashi¹, Akifumi Hagiwara¹, Shohei Fujita^1,2, Toshiaki Akashi¹, Akihiko Wada¹, Masaaki Hori³, and Shigeki Aoki^1
1Department of Radiology, Juntendo University Graduate School of Medicine, Tokyo, Japan, ²Department of Radiology, The University of Tokyo, Tokyo, Japan, ³Department of Radiology, Toho University Omori Medical Center, Tokyo, Japan

Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) are neurodegenerative disorders associated with corticobasal degeneration pathology. A previous study evaluated white matter (WM) alteration using diffusion tensor imaging; however, the details are unclear due to the crossing fiber. This study evaluated cross-sectional and longitudinal WM changes in PSP and CBS using fixel-based analysis. This study also demonstrated consistent cross-sectional and longitudinal WM degeneration with previous histopathological studies and higher sensitivity than classical magnetic resonance imaging findings in differentiating PSP and CBS. Our results suggest that FBA can be a biomarker to classify PSP and CBS and estimate disease progression.

Peng Wang¹, Xinchun Li¹, Qi Wan¹, Wenjin Zou², Yihao Guo³, Mengzhu Wang⁴, Jianfeng Hu¹, Yu Peng¹, Xiaoying Xia¹, Xiaobin Xie¹, and Jieqiong Liu^1
1Department of Radiology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China, ²The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China, ³MR Collaboration, Siemens Healthineers Ltd., Guangzhou, China, ⁴MR Scientific Marketing, Siemens Healthineers, Guangzhou, China

In the current study, we assessed possible alterations of brain white matter (WM) microstructure in patients with obstructive sleep apnea (OSA) using generalized q-sampling imaging (GQI). We found higher normalized quantitative anisotropy values of the bilateral superior longitudinal fasciculus, uncinate fasciculus, fornix, and corpus callosum bundle in the OSA group vs controls, which were related to multiple clinical indices of OSA.

Yuhao Lin¹, Xiaofei Lv², Jiahui Liang², Yanqiu Feng¹, and Xinyuan Zhang^1
1School of Biomedical Engineering, Southern Medical University, Guangzhou, China, ²Department of Medical Imaging, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Guangzhou, China

Based on the multi-shell diffusion MRI data acquisition and tract-based spatial statistics (TBSS), we conducted a longitudinal study to explore the changing patterns of DKI and NODDI metrics after radiotherapy for nasopharyngeal carcinoma (NPC) patients. We found most of the significant regions showed a “self-recovery” mechanism but the temporal lobe regions show a progressive changing pattern over time after RT. Besides, we also found that the change of DKI metrics has a stronger dose-correlation than DTI and NODDI metrics. Our study indicates the DKI and NODDI metrics can provide more comprehensive brain microstructure changes compared with conventional DTI.

Shuyue Wang¹, Fan Zhang², Peiyu Huang¹, Hui Hong¹, Yeerfan Jiaerken¹, Xinfeng Yu¹, Ruiting zhang¹, Qingze Zeng¹, Yao Zhang¹, Ron Kikinis², Yogesh Rathi², Nikos Makris², Ofer Pasternak², Minming Zhang¹, and Lauren J. O’Donnell^2
1The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China, ²Harvard Medical School, Boston, MA, United States

We assess microstructural alterations in superficial white matter (SWM) in cerebral small vessel disease (CSVD) and evaluate their contributions to the decline in processing speed, which is the main dysfunction in CSVD. We identify that the significant decline in processing speed may relate to the involvement of WMH in the SWM under high burden of disease. The increased extracellular free water may be the main SWM microstructural change under low burden of disease. These observations suggest that the SWM may serve as a potential target for monitoring pathophysiological processes in CSVD. This study extends the current understanding of CSVD-related dysfunction.

Marshall A Dalton¹, Jinglei Lv¹, Arkiev D'Souza¹, and Fernando Calamante^1
1The University of Sydney, Sydney, Australia

The hippocampus is a brain structure central to a broad range of cognitive functions including episodic memory. In recent years, we have developed a greater understanding of the structural and functional connectivity of the human hippocampus. Despite these advances, we lack a detailed understanding of structure-function relationships of cortico-hippocampal connectivity. We addressed this gap by combining high-quality data from the Human Connectome Project with cutting-edge fibre-tracking and track-weighted dynamic functional connectivity methods to quantitatively characterise the relationship between anatomical and functional connectivity of the human hippocampus. Our results contribute to ongoing efforts to characterise structure-function relationships of the hippocampus.

Miaomiao Wang¹, Congcong Liu¹, Xianjun Li¹, and Jian Yang^1
1the first affiliated hospital of Xi'an Jiaotong university, Xi'an, China

Punctate white matter lesion (PWML) is the most common injury in neonates. Due to newborns are a vulnerable population, the limited imaging protocols are not sufficient to fully understand the injury. Le Bihan et.al recently proposed a virtual MR elastography (vMRE) method based on multiple b-values diffusion sequences, which is attractive for evaluation of brain development and injury. This study aims to quantitatively assess the stiffness of PWML using vMRE. Compared with white matter regions, a significant increased virtual sheer stiffness is observed in lesions, and it may be a feasible clinical evaluation of the pathophysiological state of brain tissue.

Bowen Li¹, Huajun She¹, Quan Chen², Zhijun Wang¹, and Yiping P. Du^1
1School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China, ²Department of Radiology, Stanford University, Stanford, CA, United States

A grouping sparse coding (Group-SC) model is used in this study for the acceleration of myelin water content quantification. Images with improved quality are obtained using the Group-SC algorithm, in the aspect of minimal artefacts and good data consistency with fully-sampled labels. Myelin water fraction (MWF) maps reconstructed using Group-SC demonstrate more natural spatial distribution of myelin water in the brain. The proposed Group-SC algorithm has demonstrated its potential for the acceleration of the myelin water content quantification at R = 6.

Ryuna Kurosawa¹, Hajime Yokota², Takafumi Yoda¹, Takayuki Sada¹, Koji Matsumoto¹, Takashi Namiki³, Masami Yoneyama³, Guillaume Gilbert⁴, Yoshitada Masuda¹, and Takashi Uno^2
1Department of Radiology, Chiba Univercity Hospital, Chiba, Japan, ²Diagnostic Radiology and Radiation Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan, ³Philips Japan, Tokyo, Japan, ⁴Philips Canada, Mississauga, ON, Canada

Demyelination assessment with MRI for multiple sclerosis (MS) is a reliable biomarker for monitoring disease progression. Recently, inhomogeneous magnetization transfer (ihMT) combined sequencing has been developed for myelin-specific imaging. The purpose of this study was to evaluate ihMT in delineating MS lesions in the spinal cord by comparing the conventional imaging methods. The lesion-to-white matter contrast-to-noise ratio (CNR) on ihMT was significantly higher than the other methods. The qualitative analysis revealed clarity of lesion detection, but false positives were a concern. Our results in MS patients suggest that ihMT may be a helpful sequence for lesion detection.

Xiaoli Mai¹, Jilei Zhang², Junting Zou¹, Yuanyuan Xie³, Bin Wang³, and Bing Zhang^1
1Radiology Department, Nanjing Drum Tower Hospital, the affiliated hospital of Nanjing University Medical School, Nanjing, China, ²Philips Healthcare, Shanghai, China, ³Nanjing Drum Tower Hospital, Nanjing, China

Stromal cell transplantation plays an important role in the treatment of traumatic spinal cord injury (SCI). The multi-parameter MRI, including DTI, T2 , T2* mapping and QSM , of all beagles were performed before and after operation. We found that the transplanted stromal stem cells with Ruicun-labeled in the injured spinal cord could be quantified by QSM within 28 days after transplantation. FA value can be used to quantitatively evaluate the integrity of spinal fibers and the recovery of spinal nerve function. Thus, MRI can used to track  the dynamic changes of SPIONS labeled stromal stem cells transplanted.

Meng-Ze Zhang¹, Han-Qiang Ou-Yang^1,2,3, Chun-Jie Wang¹, Jian-Fang Liu¹, Dan Jin¹, Xian-Chang Zhang⁴, Qiang Zhao¹, Xiao-Guang Liu^1,2,3, Zhong-Jun Liu^1,2,3, Ning Lang¹, Xing-Wen Sun¹, Liang Jiang^1,2,3, and Hui-Shu Yuan^1
1Peking University Third Hospital, Beijing, China, ²Engineering Research Center of Bone and Joint Precision Medicine, Beijing, China, ³Beijing Key Laboratory of Spinal Disease Research, Beijing, China, ⁴MR Collaboration, Siemens Healthineers Ltd, Beijing, China

This study used radiomics based on T2*-weighted imaging (T2*WI) and neurite orientation dispersion and density imaging (NODDI) to predict the short-term recovery of patients with cervical spondylotic myelopathy (CSM). By classifying patients into good and poor outcomes based on the 3-month recovery rate, we found both T2*WI- and NODDI-based radiomic features to have good prognostic power. Furthermore, radiomic score based on NODDI was an independent predictor, whereas the other features were not. These findings suggest that radiomics based on NODDI has good prognostic power for CSM.

Xin Ge^1,2, Xueying Huang², Aijun Wang², Kai Zhu², Xiaocheng Wei³, Min Li⁴, Ying Shen^1,2, Wenxiao Liu^1,2, Peng Yong^1,2, Ruirui Lv^1,2, Xuhong Yang^1,2, and Xiaodong Wang^2
1Ningxia Medical University, Yinchuan, China, ²General Hospital of Ningxia Medical University, Yinchuan, China, ³GE Healthcare, MR Research, Beijing, China, Beijing, China, ⁴GE Healthcare, MR Enhancement Application, Beijing, China, Beijing, China

This work sought to investigate the performance of synthetic MRI, ASL and DWI in differentiating LGGs from HGGs as compared to conventional MRI. It was concluded that the T1 and PD from synthetic MRI can be used as novel quantitative imaging biomarkers for grading gliomas. Combining T1, PD, CBF and ADC may explore as an effective strategy to improve the ability for discriminating gliomas grade, and outperformed conventional approaches.

Peng Wang¹, Yang Gao¹, Qiong Wu¹, Jinlong He¹, Shenghui Xie¹, Shaoyu Wang², and Huapeng Zhang^2
1Radiology, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China, ²Siemens Healthineers, Shanghai, China

Although surgery is still the most effective treatment for diffuse glioma, patients with unresectable primary, recurrent, or multicentric illness have few options. In some cases, genotyping predictions may be useful for targeted therapy. We performed pretreatment MRI scans and genetic sequencing of tumor tissue, as well as correlation analysis, to see if essential molecular genetic events linked with diffuse glioma may be predicted in advance and noninvasively. The findings revealed that the MAP-MRI model can reliably predict tumor genotyping with high robustness and diagnostic validity, implying that it could be useful in the development of more standardized treatment.

Tomohiko Horie¹, Natsuo Konta¹, Masateru Kawakubo², Hiroshi Hamano³, Han Soo Chang⁴, Tetsu Niwa⁵, Kagayaki Kuroda⁶, and Mitsunori Matsumae^4
1Department of Radiology, Tokai University Hospital, Isehara, Japan, ²Department of Health Sciences, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan, ³Philips Japan, Shinagawa, Japan, ⁴Department of Neurosurgery, Tokai University School of Medicine, Isehara, Japan, ⁵Department of Radiology, Tokai University School of Medicine, Isehara, Japan, ⁶6) Department of Human and Information Science, School of Information Science and Technology, Tokai University, Hiratsuka, Japan

There are still many unclear issues in the motions of the spinal cord. This study is the first report to use optical flow analysis for quantitative evaluation of spinal cord motions. In the study of healthy volunteers, we found large displacement of the upper thoracic spinal cord. The study of clinical cases revealed that the spinal cord displacement changed before and after surgery. Therefore, these results suggested that quantitative evaluation of spinal cord motions is feasible using optical flow analysis.

Shuang Hu¹, BoWen Hou¹, YiTong Li¹, Yao Zhang¹, Weiyin Vivian Liu², and XiaoMing Li^1
1Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology, Wuhan,China, China, ²GE Healthcare, Beijing, China., China

Lumbar radiculopathy is a worldwide cause of disability. Mechanical compression of nerve root may lead to nerve inflammatory changes. Peripheral blood vessels overlapping with inflammatory changes can make radiologists confused and result misdiagnosis. To differ lesions from vessels in lumbosacral plexus nerve imaging, three-dimensional motion-sensitized driven equilibrium prepared rapid gradient echo (3D-MERGE) and three-dimensional multiecho in the steady-state acquisition (3D-MENSA) were investigated. Our study showed 3D-MENSA images showed greater nerve-to-vein CNR and CR than 3D-MERGE and the measurement repeatability of the same observer was good. Overall, 3D-MENSA sequence provided images with superior vascular suppression and offered better conspicuity of LSP.