Tales Santini¹, Minseok Koo¹, Nadim Farhat¹, Vinicius P. Campos², Salem Alkhateeb¹, Marcelo A. C. Vieira², Meryl A Butters¹, Caterina Rosano¹, Howard J Aizenstein¹, Joseph Mettenburg¹, Enrico M. Novelli¹, and Tamer S Ibrahim^1
1University of Pittsburgh, Pittsburgh, PA, United States, ²University of Sao Paulo, Sao Carlos, Brazil

Sickle cell disease (SCD) is an inherited hemoglobinopathy that can cause organ dysfunction such as cerebral vasculopathy and neurological complications. We explored whether SCD may be also associated with abnormalities in hippocampal subregions. We analyzed 7T MRI images from individuals with SCD and matched controls. Individuals with SCD had a significantly smaller volume of the DG+CA2+CA3 hippocampal region. Other hippocampal subregions also showed a trend towards smaller volumes in the SCD group. Further studies are necessary to investigate the mechanisms that lead to structural changes in the hippocampus subfields and their relationship with cognitive performance in SCD.

Baolin Wu¹, Feifei Zhang¹, Zhiyun Jia^1,2, and Qiyong Gong^1,3
1Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China, ²Department of Nuclear Medicine, West China Hospital of Sichuan University, Chengdu, China, ³Psychoradiology Research Unit of Chinese Academy of Medical Sciences (2018RU011), Chengdu, China

Although patients with end-stage renal disease (ESRD) have shown disrupted connectivity within and between resting-state functional networks, the patterns of change in dynamic functional network connectivity (FNC) remain unclear. The present work is the first study to investigate the dynamic functional connectivity in patients with ESRD. Patients with ESRD showed state-specific FNC disruptions and altered dynamic FNC properties. Furthermore, the total number of transitions was related to cognitive performance in those patients. These findings provided new insights into the pathophysiological mechanism of their cognitive deficits.

Anna Lavrova¹, Wouter Teunissen², Esther Warnert², Martin van den Bent³, Vladimir Cheremisin¹, and Marion Smits^2
1Radiology, Saint Petersburg University, Saint Petersburg, Russian Federation, ²Radiology, Erasmus MC, Rotterdam, Netherlands, ³Neurology, Erasmus MC, Rotterdam, Netherlands

Dynamic susceptibility contrast-enhanced (DSC) perfusion is an established standard in the assessment of brain tumor perfusion. This study aims to assess the feasibility of using non-contrast arterial spin-labeling (ASL) instead of DSC.

Bhaswati Roy¹, Sarah Choi², Matthew J. Freeby ³, and Rajesh Kumar^1,4,5,6
1Anesthesiology, University of California Los Angeles, Los Angeles, CA, United States, ²School of Nursing, University of California Los Angeles, Los Angeles, CA, United States, ³Medicine, Endocrinology - Diabetes and Metabolism, University of California Los Angeles, Los Angeles, CA, United States, ⁴Bioengineering, University of California Los Angeles, Los Angeles, CA, United States, ⁵Radiological Sciences, University of California Los Angeles, Los Angeles, CA, United States, ⁶Brain Research Institute, University of California Los Angeles, Los Angeles, CA, United States

Patients with Type 2 diabetes mellitus (T2DM) show cognitive and mood changes, and brain tissue injury in those regulatory regions. However, underlying cause of tissue damage in cognition and mood regulatory sites, and their associations with these functional deficits in T2DM remain unclear. We evaluated cerebral blood flow (CBF) in T2DM patients over controls, and found changes in the frontal and prefrontal cortices, cerebellum, hippocampus, cingulate, insula, thalamus, and basal-forebrain, sites involved regulating mood and cognition. Significant correlations emerged between CBF and functional deficits in T2DM, including mood and cognition symptoms, implying the altered hemodynamic contributing to the functional deficits.

Shilong Tang¹ and Lisha Nie^2
1Children's Hospital of Chongqing Medical University, Chongqing, China, ²GE Healthcare, MR Research China, Beijing, Beijing, China

In the central nervous system, iron is a cofactor for many metabolic processes and aminergic neurotransmitter synthesis, and iron plays an important role in brain development from the fetal to adolescent stages. There have been many reports about the application of quantitative magnetic susceptibility mapping (QSM) to detect iron content in the normal adult brain at home and abroad and few reports about the application of QSM to detect iron content in the normal brain of children.

Fedel Machado-Rivas^1,2, Lina Acosta Buitrago³, Jungwhan J Choi^1,2, Onur Afacan^1,2, Clemente Velasco-Annis¹, Simon K Warfield^1,2, Ali Gholipour^1,2, and Camilo Jaimes^1,2
1Radiology, Boston Children's Hospital, Boston, MA, United States, ²Radiology, Harvard Medical School, Boston, MA, United States, ³Universidad del Rosario, Bogota, Colombia

Brain growth trajectories of fetal subjects with congenital diaphragmatic hernia (CDH) were compared to typically developing fetuses. T2-weighted SSFSE acquisitions were reconstructed to a super-resolution volume and atlas-based segmentations of brain structures were propagated. Gestational age, sex, segment volumes, and morphological hernia metrics (for CDH subjects)  were analyzed in 71 fetuses with CDH and in 50 controls. We found lower brain volumes relative to normal fetuses in the developing white matter, hippocampus, diencephalon, and deep gray structures. Metrics associated with greater hernia severity were associated with lower volumes. Furhermore, our analysis shows that right-sided hernias were associated with lower volumes. 
 

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

MR neurography (MRN) is a useful technique to evaluate damaged peripheral nerves showing increased signal intensity and enlarged nerve diameter. Although various MRN sequences have been developed, the inter-rater reliability of MRN have rarely been evaluated. Therefore, the purpose of this study was to evaluate inter-rater reliability of sciatic nerve evaluation with MRN sequences: T2WI, 3D-STIR, T2-FFE, 3D-iNerveVIEW, Diffusion-neurography, DTI, and pcDSDE. Measured diameters varied among the sequences. 3D-iNerveVIEW showed a high inter-rater reliability for signal measurements. In MRN, it is important to understand the characteristics of each sequence.

Celine Berger^1,2, Claudia Lenz^1,2, Melanie Bauer^1,2, Eva Scheurer^1,2, and Christoph Birkl^3
1Institute of Forensic Medicine, Department of Biomedical Engineering, Basel, Switzerland, ²Institute of Forensic Medicine, Health Department Basel-Stadt, Basel, Switzerland, ³Department of Neuroradiology, Medical University of Innsbruck, Austria

White matter R₂^* imaging is sensitive to the fiber orientation with respect to the main magnetic field. This study compared fiber orientation dependent R₂^* of white matter in post mortem (pm) in situ and in vivo based on an identical technical approach using diffusion tensor imaging to estimate the fiber angle. R₂^* increased with increasing fiber angle in both groups, whereby a decreased R₂^* orientation sensitivity was observed post mortem compared to in vivo. This may be mainly caused by the decreased pm brain temperature compared to in vivo conditions leading to reduced diffusion and by tissue decomposition after death.

Nikhil Deveshwar^1,2 and Peder E. Z. Larson^1,2
1Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, ²UC Berkeley - UCSF Graduate Program in Bioengineering, Berkeley and San Francisco, CA, United States

This work presents a study detailing the reproducibility of ultrashort-T₂* measurements using a novel UTE relaxometry method. Generated parameter maps show similar looking structures in terms of intensity and definition. Furthermore, the distributions of the ultrashort-T₂* fractional component in various brain ROIs show similar distributions and have low coefficients of variance. These results suggest the proposed UTE relaxometry method is reproducible and can reliably measure parameters of the brain ultrashort-T₂* component.

Ethan Danielli^1,2, David Stillo^1,2, Rachelle Ho^3,4, Carol DeMatteo^3,5, Geoffrey B Hall⁴, Nicholas A Bock⁴, John F Connolly^1,4,5,6, and Michael D Noseworthy^1,2,5,7,8
1School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada, ²Imaging Research Centre, St. Joseph's Healthcare Hamilton, Hamilton, ON, Canada, ³School of Rehabilitation Sciences, McMaster University, Hamilton, ON, Canada, ⁴Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, ON, Canada, ⁵ARiEAL Research Centre, McMaster University, Hamilton, ON, Canada, ⁶Department of Linguistics, McMaster University, Hamilton, ON, Canada, ⁷Department of Electrical and Computer Engineering, McMaster University, Hamilton, ON, Canada, ⁸Department of Radiology, McMaster University, Hamilton, ON, Canada

Although concussion diagnosis is often subjective, DTI can effectively quantify brain white matter damage. In this study, demographic and DTI metrics were compared between 26 paediatric concussion subjects against 49 healthy age and sex matched controls. FA was significantly reduced in injured brain regions and correlated with younger age and worsened symptoms. RD was significantly increased in injured brain regions and correlated with younger age and the interaction between time to scan and PCSS score. Based on these results, age affects concussion severity in younger children resulting in worse symptoms and a greater number of abnormal brain regions.

Jodi Karlyn Watt^1,2,3, Stefan Pszczolkowski^1,2,3, Yue Xing^1,2,3, Christopher Tench^1,2,3, Dorothee Auer^1,2,3, and Alzheimer's Disease Neuroimaging Initiative^4
1Division of Clinical Neuroscience, University of Nottingham, Nottingham, United Kingdom, ²Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom, ³NIHR Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, United Kingdom, ⁴Alzheimer's Disease Neuroimaging Initiative, Los Angeles, CA, United States

A functional biomarker of age-related cognitive decline is yet to be elucidated but would be desirable to better understand detrimental and protective processes in order to promote cognitive health for the elderly. Challenges arise from multiple sources of variance across individuals and within brain perfusion maps with an unknown link between local or network function and clinical tests of global cognition. Principal Component Analysis provides the opportunity to address some of these knowledge gaps, by defining this relationship and relating this to underlying anatomical regions. 

Tasfiya Islam¹, Mengting Liu¹, Dae Lim Koo², Ryan Cabeen¹, Eunyeon Joo³, and Hosung Kim^1
1USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States, ²Department of Neurology, Boramae Medical Center, Seoul National University College of Medicine, Seoul, Korea, Republic of, ³3Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Samsung Biomedical Research Institute, Seoul, Korea, Republic of

     Obstructive sleep apnea (OSA) possibly affects individuals cognitively. To identify potential neurocognitive drawbacks for these patients, diffusion MRI and T1 neuroimaging data were collected from 148 OSA and healthy subjects. Structural brain networks were constructed using diffusion MR images. Network topological characteristics and localized connectivity were performed on diffusion related network along with brain and behavior relationships. It was found that the OSA individuals generally had greater modularity network measure, and impaired connectivity in several regions in the frontal lobe. Also, some of the brain connections and behavior relationships that were established in healthy subjects were disrupted for OSA patients.

Cong Sun¹, Aocai Yang¹, Jiaguang Song², Minhui Ouyang³, Jinxia Zhu⁴, Lei Xue⁵, Hao Huang^3,6, and Gunagbin Wang^1
1Radiology, Shandong Medical Imaging Research Institute, Cheeloo College of Medicine, Shandong University, Jinan, China, ²Ultrasound, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, China, ³Radiology Research, Children’s Hospital of Philadelphia, Philadelphia, PA, United States, ⁴MR Collaboration, Healthcare Siemens Ltd., Beijing, China, ⁵MR Application, Siemens Healthineers Ltd., Jinan, China, ⁶Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States

We investigated the early changes of brain oxygenic metabolism in fetuses with complex congenital heart disease (CHD) and in normal fetuses across gestational ages. Using quantitative susceptibility mapping (QSM), we measured the venous blood oxygen saturation (SvO2) in utero of 22 fetuses with complex CHD and 88 healthy pregnancy controls. The SvO2 in normal fetuses was found to have no age-related change. SvO2 values were significantly higher in the CHD fetuses (80.8%±4.6%) than in the gestational age-matched normal fetuses (75.7%±8.0%) (p=0.038); which is evidence of altered human fetal brain oxygenic metabolism during the early stages of brain development.

Jan Kufer¹, Christine Preibisch^1,2, Samira Epp¹, Jens Goettler^1,3, Kilian Weiss⁴, Mikkel Bo Hansen⁵, Claus Zimmer¹, Kim Mouridsen⁵, Fahmeed Hyder³, and Stephan Kaczmarz^1,3
1Department of Neuroradiology, School of Medicine, Technical University of Munich (TUM), Munich, Germany, ²Department of Neurology, School of Medicine, Technical University of Munich (TUM), Munich, Germany, ³Department of Radiology & Biomedical Imaging (MRRC), Yale University, New Haven, CT, United States, ⁴Philips Healthcare, Hamburg, Germany, ⁵Department of Clinical Medicine, Aarhus University, Aarhus, Denmark

Clinical imaging of the oxygen extraction fraction (OEF) is highly promising to improve stratification of patients with various neurological diseases. Measurement of OEF by multiparametric quantitative blood oxygen level dependent (mqBOLD)-MRI could greatly increase clinical applicability compared to the current gold standard PET. Furthermore, oxygen extraction capacity (OEC) has recently emerged as another MRI-based biomarker of cerebral oxygenation. However, studies comparing both MRI techniques to PET reference data are still lacking. Here, we present data from an MRI study in young healthy volunteers, demonstrating good agreement of both, MRI-based OEF and OEC, with PET data from a similar subject group.

Tzu-chen Yeh^1,2, Chou-ming Cheng³, and Chi-che Chou^3
1Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan, ²Institue of Brain Science, National Yang-Ming University, Taipei, Taiwan, ³Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan

Carbogen-based cerebrovascular reserve (CO₂-CVR), derived from 90 normal subjects, was constructed for data-based approaches or analysis. Tissue, territorial and cortical specificities of CO₂-CVR were evaluated by regions of interest (ROI) approaches. Global ratio of GM/WM CO2-CVR was about 1.57. Territorial and cortical specificities of CO₂-CVR demonstrated (1) limited CO₂-CVR in territories of posterior circulation which supported the pathophysiology of posterior reversible encephalopathy syndrome and (2) vital function in distal territories of anterior cerebral artery as verified by cortical parcellation with the highest of CO₂-CVR at ventral portion of Brodmann area 23 (co-localized with posterior cingulate cortices of default mode network).

Thomas Troalen¹, Arnaud Le Troteur², Sylviane Confort-Gouny², Patrick Vioux², Claire Costes², Lauriane Pini², Jean-Philippe Ranjeva², Maxime Guye², and Ludovic de Rochefort^2
1Siemens Healthcare SAS, Saint-Denis, France, ²CRMBM UMR7339 CNRS Aix-Marseille Université, Marseille, France

Advanced quantitative susceptibility mapping techniques allow to jointly estimate R2* and QSM in the brain. This work aims at comparing several multi gradient-recalled echo sequences in terms of coil setup and acceleration factors using available product sequences and modern hardware. In addition, an automatic and standardized post-processing pipeline is proposed for clinical studies. We show that quantitative values do not differ from the head coil and acceleration factor that were used, thus allowing for a millimetric whole brain coverage within 5 minutes scan time.

Eva YW Cheung¹, Patrick KC Chiu², YF Shea², Joseph SK Kwan³, and Henry KF Mak^1
1The University of Hong Kong, Hong Kong, Hong Kong, ²Queen Mary Hospital, Hong Kong, Hong Kong, ³Imperial College London, London, United Kingdom

Interhemispheric functional connectivity and 18F-flutametamol PET 

Archith Rajan¹, Apurva Shah¹, Madhura Ingalhalikar¹, and Nandini C Singh^2
1Symbiosis Centre for Medical Image Analysis, Symbiosis International(Deemed) University, Pune, India, ²Language,Literacy and Music Lab, National Brain Research Centre, Gurgaon, India

Pre-existing structural connectivity could well explain predisposition to musical aptitude. The study aimed to associate Individual differences in High Angular Resolution Diffusion Imaging (HARDI) derived structural connectivity to music perception abilities as assessed by the performance in a music perception test. An increased whole brain connectivity was found to be associated with increased performance especially in the sequential music perception measures that comprised of Standard Rhythm, Embedded Rhythm, Accent and Melody. A prevalence of interhemispheric connectivity over intrahemispheric connectivity was also observed. Distinct structural connectivity patterns could thus be a determinant of sequential processing aptitude in music.

Jiaen Liu¹, Peter van Gelderen¹, Jacco A. de Zwart¹, and Jeff H. Duyn^1
1AMRI, LFMI, NINDS, National Institutes of Health, Bethesda, MD, United States

High-resolution T₂*-weighted 7 T MRI can be used to delineate intracortical structure owning to its high signal-to-noise and contrast-to-noise ratio. However, subject motion remains a major challenge to obtain reliable high-resolution data; the long scan time and increased sensitivity of T₂*-weighted signal at 7 T to motion and motion-induced B₀ fluctuation make high-resolution T₂*-weighted MRI particularly motion sensitive. In this study, the performance of a previously developed navigator-based motion and B₀ correction approach was evaluated for intracortical imaging.

Yan-Chao Liu¹, Bo-Hao Zhang², De-Sheng Xuan², Xue-Yuan Wang², Kai-Yu Wang³, Xin Zhao², and Xiao-An Zhang^2
1Department of Radiology, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China, ²Department of Radiology, the Third Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China, Zhengzhou, China, ³MR Research China, GE Healthcare, Beijing 100000, PR China, Beijing, China

Fetal brain development is an ongoing process, and it is necessary to find a sensitive monitoring tool to detect potential brain developmental abnormalities earlier. In this work, T1Mapping allowed quantitative assessment of fetal brain development.