Daisuke Sawamura^1,2, Ryusuke Suzuki³, Shinya Sakai¹, Keita Ogawa⁴, Xinnan Li², Hiroyuki Hamaguchi², and Khin Khin Tha^5
1Department of Rehabilitation Science, Hokkaido University, Sapporo, Japan, ²Department of Biomarker Imaging Science, Hokkaido University, Sapporo, Japan, ³Department of Medical Physics, Hokkaido University Hospital, Sapporo, Japan, ⁴Department of Rehabilitation, Hokkaido University Hospital, Sapporo, Japan, ⁵Global Center for Biomedical Science and Engineering, Hokkaido University Faculty of Medicine, Sapporo, Japan

Little is known about how microstructural and functional neuroplasticity occurs upon cognitive training and the relationship between cognitive training-derived brain changes and cognitive performance. This prospective study aimed to elucidate cognitive training-derived neuroplasticity and the mechanism underlying transfer effects using diffusion spectrum imaging (DSI) and resting-state functional MRI (rsfMRI). The results suggest that the right inferior parietal lobule and its neural connections and the right cerebellar vermis may modulate the far-transfer effect.

Michele Guerreri¹, Thomas Villemonteix^2,3, Whitney Stee³, Evelyne Balteau⁴, Philippe Peigneux^3,4, and Hui Zhang^1
1Computer Science & Centre for Medical Image Computing, University College London, London, United Kingdom, ²Laboratoire de Psychopathologie et Neuropsychologie, Saint Denis, Paris 8 Vincennes - St Denis University, Paris, France, ³Neuropsychology and Functional Neuroimaging Research Group (UR2NF) at the Centre for Research in Cognition and Neurosciences (CRCN), Université Libre de Bruxelles, Brussels, Belgium, ⁴Cyclotron Research Centre, University of Liège, Liège, Belgium

We use model-based diffusion MRI to assess microstructural changes associated with short-term plasticity. Neuroplasticity changes are the foundation of experience. These mechanisms include microstructural rearrangements which can manifest even after short learning episodes. DTI has proven effective in highlighting such changes. However, the connection with the underlying microstructural processes remains speculative. Biophysical modelling can help interpreting such changes. We use NODDI and CHARMED models to examine MD changes obtained in a spatial navigation task. NODDI’s FWF and CHARMED’s hMD share similar cortical patterns of decrease as MD. FWF exhibited higher sensitivity than MD and hMD to capture microstructural changes.

Stefanie A. Tremblay^1,2, Anna-Thekla Jäger³, Julia Huck¹, Chiara Giacosa¹, Stephanie Beram¹, Uta Schneider³, Sophia Grahl³, Arno Villringer^3,4,5,6, Christine Lucas Tardif^7,8, Pierre-Louis Bazin^3,9, Christopher J Steele^3,10, and Claudine J. Gauthier^1,2
1Physics, Concordia University, Montreal, QC, Canada, ²Montreal Heart Institute, Montreal, QC, Canada, ³Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, ⁴Clinic for Cognitive Neurology, Leipzig, Germany, ⁵Leipzig University Medical Centre, IFB Adiposity Diseases, Leipzig, Germany, ⁶Collaborative Research Centre 1052-A5, University of Leipzig, Leipzig, Germany, ⁷Biomedical Engineering, McGill University, Montreal, QC, Canada, ⁸Montreal Neurological Institute, Montreal, QC, Canada, ⁹Faculty of Social and Behavioral Sciences, University of Amsterdam, Amsterdam, Netherlands, ¹⁰Psychology, Concordia University, Montreal, QC, Canada

To characterize the temporal dynamics of plasticity, we conducted a longitudinal MRI study at ultra-high field (7T) during the learning process of a sequential visuomotor task, in a learning and control group. WM microstructure was altered in the tracts underlying the primary motor and sensorimotor cortices, and in tracts adjacent to the right supplementary motor area (SMA), where changes in functional connectivity were also found in this cohort. Our study provides evidence for short-term white matter plasticity in the sensorimotor network, where the SMA would play a key role in linking the spatial and motor aspects of motor sequence learning.

Xinnan Li¹, Daisuke Sawamura², Hiroyuki Hamaguchi¹, Yuta Urushibata³, Thorsten Feiweier⁴, Keita Ogawa⁵, and Khin Khin Tha^1,6
1Department of Biomarker Imaging Science, Graduate School of Biomedical Science and Engineering, Hokkaido University, Sapporo, Japan, ²Department of Functioning and Disability, Faculty of Health Sciences, Hokkaido University, Sapporo, Japan, ³Siemens Healthcare K.K., Tokyo, Japan, ⁴Siemens Healthcare GmbH, Erlangen, Germany, ⁵Department of Rehabilitation, Hokkaido University Hospital, Sapporo, Japan, ⁶Global Center for Biomedical Science and Engineering, Faculty of Medicine, Hokkaido University, Sapporo, Japan

A four-week neurocognitive training of spatial attention and working memory was conducted in 21 volunteers. A change in tissue microstructure was tested by using double diffusion encoding MRI, which revealed a decrease in μFA in the left middle frontal gyrus. This decrease showed a significant negative correlation with the changes in the response time as assessed by the orienting attention network test.

Nicolas Delinte¹, Claire Gosse^2,3, Laurence Dricot³, Quentin Dessain¹, Mathieu Simon¹, Benoit Macq¹, Marie Van Reybroeck^2,3, and Gaetan Rensonnet^1
1ICTEAM, UCLouvain, Louvain-la-Neuve, Belgium, ²IPSY, UCLouvain, Louvain-la-Neuve, Belgium, ³IoNS, UCLouvain, Brussels, Belgium

Dyslexia is a deviant development of both reading and spelling abilities affecting 5-12 % of children, yet the microstructural changes it induces in the white matter (WM) remain incompletely understood. This study analyzed multi-shell diffusion MRI on a population of 17 dyslexic children and 18 controls. Advanced models (Diamond & Microstructure Fingerprinting), able to separately characterize intersecting fascicles within a voxel, obtained stronger correlations with children's reading and spelling performances than traditional DTI and showed increased sensitivity. The novel indices, obtained from these models, suggested refined interpretations of the microstructural characteristics of dyslexia in WM pathways. 

Davood Karimi¹, Onur Afacan¹, Clemente Velasco-Annis¹, Camilo Jaimes¹, Caitlin Rollins¹, Simon Warfield¹, and Ali Gholipour^1
1Boston Children's Hospital, Harvard Medical School, Boston, MA, United States

Diffusion weighted magnetic resonance imaging (DW-MRI) of fetal brain is challenged by fetal and maternal motion, low signal-to-noise ratio and short scan times. Hence, there is a need for methods that can accurately estimate the parameters of interest from small numbers of noisy measurements. We propose a deep learning method for accurate and robust estimation of color fractional anisotropy as a measure of brain architecture from fetal DW-MRI scans. We also propose methods for simulating realistic training data. Evaluations on an independent cohort of fetal DW-MRI scans show that the proposed method is significantly more accurate than standard methods.

Xueyuan Wang¹, Bohao Zhang², Xianglong Liu³, Kaiyu Shang⁴, Jinxia Guo⁴, Xin Zhao¹, and Xiaoan Zhang^1
1Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China, Zhengzhou, China, ²College of Chemistry, Zhengzhou University, Zhengzhou, China, Zhengzhou, China, ³Zhengzhou Central Hospital Affiliated to Zhengzhou University, Zhengzhou, China, Zhengzhou, China, ⁴GE Healthcare, MR Research China, Beijing, China, Beijing, China

Diffusion tensor imaging (DTI) is currently the only non-invasive technology available to evaluate the damage to the cerebral white matter (WM) fibers in neonates, which can reflect the occurrence of damage through the decrease of FA values. This study aims to validate the value of diffusion tensor imaging (DTI) to diagnose and predict hypoxic-ischemic brain injury (HIBD) of preterm infants to assist clinical diagnosis and treatment.

Jess E Reynolds^1,2, Emma Tarasoff³, R Marc Lebel^1,4, Bryce L Geeraert¹, and Catherine Lebel^1
1Department of Radiology, University of Calgary, Calgary, AB, Canada, ²Telethon Kids Institute, The University of Western Australia, Perth, Australia, ³Department of Neuroscience, University of Calgary, Calgary, AB, Canada, ⁴GE Healthcare, Calgary, AB, Canada

There is a need to better understand white matter development across early childhood, as it is a time of rapid brain development that supports ongoing cognitive and behavioral maturation. Here, we aimed to apply NODDI and qihMT techniques longitudinally to provide a more specific understanding of early brain development. Consistent with diffusion MRI research, these advanced diffusion and non-diffusion methods indicated earlier development of central tracts compared to more peripheral regions. NODDI and qiHMT metrics demonstrate that white matter development during early childhood is dominated by increasing axon density, alongside ongoing myelination and slightly decreasing axon coherence.

Thijs Dhollander¹, Claire Kelly^1,2, Ian Harding^3,4, Wasim Khan³, Richard Beare¹, Jeanie Cheong^2,5,6, Lex Doyle^2,5,6,7, Marc Seal^1,7, Deanne Thompson^1,2,7, and Peter Anderson^2,8
1Developmental Imaging, Murdoch Children's Research Institute, Melbourne, Australia, ²Victorian Infant Brain Studies (VIBeS), Murdoch Children's Research Institute, Melbourne, Australia, ³Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Australia, ⁴Monash Biomedical Imaging, Monash University, Melbourne, Australia, ⁵Newborn Research, The Royal Women's Hospital, Melbourne, Australia, ⁶Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia, ⁷Department of Paediatrics, The University of Melbourne, Melbourne, Australia, ⁸Turner Institute for Brain and Mental Health and School of Psychological Sciences, Monash University, Melbourne, Australia

While many studies have used diffusion MRI to investigate white matter microstructure, fewer studies have investigated cortical grey matter microstructure. We investigated cortical microstructural tissue and fluid composition using diffusion tissue signal fractions from Single-Shell 3-Tissue Constrained Spherical Deconvolution, in a cohort of preterm-born children at 13 years of age (n=130). Compared with term-born controls (n=45), we identified several cortical regions exhibiting a relative shift from a grey matter-like composition towards a more fluid-like composition, potentially reflecting reduced cell density and increased free-water content. This illustrates the utility of 3-tissue compositional analysis for studying cortical microstructure in neurodevelopment.

Benjamin T Newman^1,2, James T Patrie³, and T Jason Druzgal^1
1Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, VA, United States, ²Brain Institute, University of Virginia, Charlottesville, VA, United States, ³Department of Public Health Sciences, University of Virginia, Charlottesville, VA, United States

Understanding how the brain develops during adolescence is important for evaluating neuronal developments that affect mental health throughout the lifespan. This study uses 3-tissue constrained spherical deconvolution (3T-CSD) to examine the relationship between brain diffusion microstructure in deep white matter ROIs and pubertal development in a cross-sectional group of 4752 adolescents. An anisotropic diffusion signal fraction was found to have a negative correlation, while an intracellular isotropic diffusion signal fraction had a positive correlation with pubertal development across the majority of axonal ROIs. These results provide evidence for complex microstructural changes in brain development within the white matter skeleton.

Suheyla Cetin-Karayumak¹, Fan Zhang¹, Tashrif Billah², Sylvain Bouix¹, Steve Pieper³, Lauren J. O'Donnell¹, and Yogesh Rathi^1
1Brigham and Women's Hospital and Harvard Medical School, Boston, MA, United States, ²Brigham and Women's Hospital, Boston, MA, United States, ³Isomics, Boston, MA, United States

This study presents our harmonization efforts on the multi-site diffusion MRI data of the ~12,000 adolescents from the Adolescent Brain Cognitive Development (ABCD) study, collected from 22 sites using Siemens, GE and Philips scanners. On the minimally preprocessed diffusion MRI data provided by the ABCD study - release 3, we first applied brain masking using our deep learning tool which showed 99% Dice overlap performance compared to the manually corrected masks. Next, we harmonized the dMRI data from 22 sites (with 45 scanner settings) using our previously-validated software. The harmonized diffusion MRI data will be shared through the NIMH data archive.

Loxlan Wesley Kasa^1,2, Terry Peters^1,2,3,4, Seyed M Mirsattari^3,4,5, Ali R Khan^1,2,3, and Roy AM Haast^1
1Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada, ²School of Biomedical Engineering, Western University, London, ON, Canada, ³Department of Medical Biophysics, Western University, London, ON, Canada, ⁴Department of Medical Imaging, Western University, London, ON, Canada, ⁵Department of CNS, Western University, London, ON, Canada

The role of the temporal pole (TP) in nonlesional temporal lobe epilepsy (‘MRI-’) has been underappreciated. Better understanding of the possible white matter (WM) microstructural changes within the TP in MRI- is important for informing resective surgery. The purpose of this study was to evaluate the use of diffusion kurtosis imaging (DKI), to detect abnormalities at specific regions along WM fibre bundles proximal to the TP in MRI- and lesional TLE (‘MRI+’). DKI was able to detect possible microstructural changes near TP in both MRI+ and MRI- subjects not clearly visible using diffusion tensor imaging metrics.

Benedictor Alexander Nguchu¹, Jing Zhao ^2,3, Yanming Wang¹, Jean de Dieu Uwisengeyimana¹, Xiaoxiao Wang¹, Bensheng Qiu¹, and Hongjun Li^2,3
1Hefei National Lab for Physical Sciences at the Microscale and the Centers for Biomedical Engineering, University of Science and Technology of China, Hefei, China, ²Department of Radiology, Beijing Youan Hospital, Capital Medical University, Beijing, China, ³School of Biological Science and Medical Engineering, Beihang University, Beijing, China

The brain activity underlying cognitive processing can be affected by HIV. We examine the ALPS index, a measure reflecting glymphatic system activity, along the perivascular space and its relationship with cognitive performance in middle-aged HIV infected patients successfully adhering to antiretroviral therapy. We found that the ALPS index was increased significantly in middle-aged HIV-infected patients receiving cART and was correlated with attention and working memory. The duration on cART was also associated with some cognitive measures. These findings suggest that ALPS index might provide an impetus for understanding cognitively relevant diffusivity changes following HIV  or long-term use of cART.

JIA-WEI Liang¹, Tang-Jun Li², Yao-Wen Liang³, Ting-Chun Lin³, Yi-Chen Lin³, Jiunn-Horng Kang^2,4, You-Yin Chen^3,5, and Yu-Chun Lo^5
1Department of Biomedical Optoelectronic, Taipei Medical University, Taipei, Taiwan, ²College of Medicine, Taipei Medical University, Taipei, Taiwan, ³Department of Biomedical Engineering, National Yang Ming University, Taipei, Taiwan, ⁴Department of Physical Medicine & Rehabilitation, Taipei Medical University, Taipei, Taiwan, ⁵Ph.D. Program for Neural Regenerative Medicine, Taipei Medical University, Taipei, Taiwan

Recently, neuroinflammation was proposed as an important role in fibromyalgia. However, the correlation between neuroinflammation and functional connection in fibromyalgia patients remained unclear. Fibromyalgia patients and healthy control participants were recruited to investigate the mechanism of fibromyalgia. Independent component analysis, diffusion kurtosis MRI and cortical thickness estimation were applied in this study. The finding implied that neuroinflammation and structural change of brain were associated with the abnormal functional connection in fibromyalgia.

Abdulaziz Alshehri^1,2, Oun Al-iedani^1,2, Jameen Arm^1,2, Neda Gholizadeh¹, Thibo Billiet³, Rodney Lea², Jeannette Lechner-Scott^1,2,4, and Saadallah Ramadan^1,2
1University of Newcastle, Newcastle, Australia, ²Hunter Medical Research Institute, Newcastle, Australia, ³Icometrix, Leuven, Australia, ⁴John Hunter Hospital, Newcastle, Australia

This study is to evaluate DTI parameters in RRMS patients with age and sex-matched HCs, and to correlate these DTI metrics values in total-brain white matter (TBWM) and white matter lesion (WML) in comparison to white matter-related volumetric measures with clinical symptoms showing the differentiation and significant P-values. DTI parameters showed a stronger correlation with clinical parameters than white matter-related volumetric measurements in RRMS. Importantly, more DTI parameters (16 metrics) with stronger clinical correlations were obtained than volume measurements (5 metrics).

Koji Kamagata¹, Christina Andica¹, Kaito Takabayashi¹, Yuya Saito¹, Wataru Uchida^1,2, Shohei Fujita¹, Toshiaki Akashi¹, Akihiko Wada¹, Kouhei Kamiya³, Masaaki Hori³, and Shigeki Aoki^1
1Department of Radiology, Juntendo University Graduate School of Medicine, Tokyo, Japan, ²Department of Radiological Sciences, Tokyo Metropolitan University, Tokyo, Japan, ³Department of Radiology, Toho University Omori Medical Center, Tokyo, Japan

Corticobasal syndrome (CBS) and progressive supranuclear palsy (PSP) are neurodegenerative disorders characterized by the deposition of the abnormal 4 microtubule-binding domain (4R) tau protein in specific brain regions. Voxel-based morphometry (VBM) has been widely used in CBS and PSD; however, the detection of pathological changes of these diseases is challenging in the early stages, including with VBM. In this study, we used free-water imaging (FWI) to evaluate gray matter (GM) microstructural changes in CBS and PSP. We determined that FWI could detect GM abnormalities, which likely reflected tau-related pathology in CBS and PSP patients more sensitively than VBM.

Xiaoyi He^1,2, Weiqiang Dou³, Hansen Schie¹, and Junying Wang^1,2
1Department of Medical Imaging, Shandong Provincial Qianfishan Hospital, The First Hospital Affiliated with Shandong First Medical University, Jinan, China, ²Shandong First Medical University, Taian, China, ³GE Healthcare, MR Research China, Beijing, China

This study aimed to investigate whether the combined 3D-arterial spin labeling (3D-ASL) and diffusion kurtosis imaging (DKI) can distinguish Binswanger’s disease (BD) patients from healthy subjects. 35 BD patients and 33 age/gender-matched controls were scanned in DKI and ASL at 3T. Compared with healthy subjects, significant alterations were found in almost all DKI & ASL relevant parameters on the major lesions and partial non-lesion regions of BD. With these findings, we thus proved that the combined DKI and 3D-ASL can be effectively tools exploring pathophysiological mechanisms and performing robust diagnostic accuracy for BD patients.

Sisi Li¹, Ke Wang², Xiao Han³, Jinchao Wang³, Wen Jiang³, Xiaodong Ma⁴, Bing Wu⁵, Yandong Liu³, Wei Liang³, and Hua Guo^1
1Center for Biomedical Imaging Research, Beijing, China, ²Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, United States, ³Beijing Jishuitan Hospital, Beijing, China, ⁴University of Minnesota, Minnesota, Minnesota, MN, United States, ⁵GE Healthcare, MR Research China, Beijing, China

Degenerative cervical myelopathy (DCM) is a chronic disease of spinal cord. The sensitivity of conventional structural T1W and T2W MRI to the diagnosis of DCM is low. Diffusion tensor imaging (DTI) can provide quantitative assessments for pre- and post-surgery spinal cord functions. However, the prognostic value of DTI metrics at the level-of-most-compression (LMC) remains controversial. Additionally, it is difficult to differentiate the clinical utility of various tracts at LMC due to severe compressions and limited resolution. This retrospective cohort follow-up study aimed to investigate the correlation of DTI metrics with clinical assessment in different tracts at non-compressed C2 level.

Daichi Murayama¹, Takayuki sakai¹, Masami Yoneyama², and Shigehiro Ochi^3
1Radiology, Eastern Chiba Medical Center, Chiba, Japan, ²Philips Japan, Tokyo, Japan, ³Eastern Chiba Medical Center, Chiba, Japan

Postoperative complications such as vertebral decompression can lead to hematoma formation and infection. The differentiation of hematoma from infection as a postoperative follow-up is important in assessing future treatment options and the need for surgery. The aim of this study was to differentiate between spinal epidural hematoma, spinal epidural abscess and pyogenic spondylitis based on the ADC and T2 values obtained using DRM. The T2 and diffusion weighted T2 (ΔT2) values were significantly higher in abscesses than in hematomas, and even higher in pyogenic spondylitis.DRM allows to differentiate hematoma from infection.

Johann ME Jende¹, Zoltan Kender¹, Christoph Mooshage¹, Sabine Heiland¹, Peter Nawroth¹, Martin Bendszus¹, Stefan Kopf¹, and Felix T Kurz^1
1Heidelberg University Hospital, Heidelberg, Germany

Nerve damage in distal polyneuropathy first becomes clinically apparent in in the legs and later in hands and arms. Previous studies could show, however, that peripheral nerve lesions in the leg predominate in the thigh and that upper limb nerve function can be impaired in early stages of the disease. We show that a decrease in sciatic nerve fractional anisotropy is associated with impaired nerve function in both upper and lower limbs for patients with diabetes and patients with prediabetes. Our findings therefore suggest that structural nerve damage in diabetic polyneuropathy already occurs at early, subclinical stages of the disease.