Laura Sirucek^1,2,3, Niklaus Zoelch^4,5, and Petra Schweinhardt^1,2
1Department of Chiropractic Medicine, Integrative Spinal Research Group, Balgrist University Hospital, University of Zurich, Zurich, Switzerland, ²University of Zurich, Zurich, Switzerland, ³Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland, ⁴Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland, ⁵Department of Psychiatry, Hospital of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Zurich, Switzerland

Preclinical studies suggest a role of altered γ-aminobutyric acid (GABA)ergic inhibitory tone in the periaqueductal grey (PAG), a key brain area for descending pain modulation, as mechanism contributing to chronic pain. The present ¹H-magnetic resonance spectroscopy study investigated GABA, and glutamate/glutamine, concentrations in the PAG of patients with chronic low back pain (CLBP). Using a point resolved spectroscopy sequence with optimized frequency alignment, adequate spectral quality was achieved and increased GABA concentrations (p=0.027) identified in CLBP patients compared to pain-free controls. This finding supports dysregulations in descending pain modulation as factor contributing to chronic pain in humans.

Yang Yang¹, Yong Li¹, Linwei Zhao¹, Hong Chen¹, Xiaoping Fan¹, and Gaowu Yan^1
1Suining Central Hospital, Chuanshan Suining, China

This study investigated the patterns of volume changes across neurofunctionally distinct hippocampal subfields in patients with chronic insomnia. The results suggested that L1 and R2 atrophy increased the risk of developing chronic insomnia approximately 3-fold, and negative emotion positively acted on the causal path of insomnia severity leading to R1 atrophy. In addition, we developed a practical and visual nomogram of individual competing risks for predicting chronic insomnia risk with high accurate predictive power based on these hippocampal subfields. Neurofunctional hippocampal subfield atrophy was a risk factor leading to chronic insomnia, contributing to understand of the etiology of insomnia.

Yasmin Geiger¹, Marganit Gonen-Shahar², Gabriel Vainstein³, Angela Ruban², and Assaf Tal^1
1Weizmann Institute of Science, Rehovot, Israel, ²Tel Aviv University, Tel Aviv, Israel, ³Maccabi Healthcare, Kefar Sava, Israel

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by irregular levels of hyperactivity, impulsivity and inattention. It is commonly linked to dopamine and norepinephrine balance. Several studies suggested connections to γ-amino butyric acid (GABA) and glutamate (Glu) imbalance in the dorsal anterior cingulate cortex (dACC). Here we use ¹H-MRS to study GABA and glutamate + glutamine (Glx) levels in the dACC of ADHD patients, before and after pharmacological treatment and compared to healthy adults. We found no metabolic difference between ADHD and control group and no change after amphetamine treatment. We found no metabolic correlation to ADHD scores.

Pengfei Zhang¹, Jun Wang¹, Wanjun Hu¹, Laiyang Ma¹, Guangyao Liu¹, Kai Ai², and Jing Zhang^1
1Department of Magnetic Resonance, Lanzhou University Second Hospital, Lanzhou, China, ²Philips Healthcare, Xi'an, China

Classic trigeminal neuralgia (CTN) has been proven related to functional or morphological alterations in critical brain regions. To test the simultaneous changes of the topological properties of structural networks (SN), functional networks (FN), as well as their couplings, we constructed SN using diffusion tensor imaging (DTI) data and FN using resting-state functional magnetic imaging (rs-fMRI) data from 29 CTN patients and 34 healthy controls (HCs). The patients showed the wide disruptions of global and local topological organizations in SN and FN, together with the abnormal coupling relationships. Our findings may provide novel perspectives for understanding the pathophysiological mechanisms of CTN.

Faezeh vedaei¹, Mahdi Alizadeh¹, George Zabrecky ¹, Nancy Wintering ¹, Anthony J. Bazzan ¹, Daniel A. Monti ¹, Andrew B. Newberg ¹, and Feroze B. Mohamed ^1
1Thomas Jefferson University, Philadelphia, PA, United States

This study provides comprehensive evaluation of functional rs-fMRI biomarkers that are associated with chronic mTBI symptoms and predicting treatment outcome and patient recovery. We evaluate the effect of medication and nutrition treatments on brain function and cognitive performance in chronic mTBI patients using resting-state fMRI metrics and neuropsychological test. We propose that treatment strategies compensate mTBI disrupt communication between brain network nodes. Our results help understanding the implication of treatment strategies in chronic mTBI patients and prediction of outcomes in brain function and cognitive recovery.

Jennifer Muller^1,2,3, KiChang Kang¹, Devon Middleton³, Mahdi Alizadeh¹, Faezeh Vedaei¹, George Zabrecky⁴, Daniel Monti⁴, Nancy Wintering⁴, Anthony J. Bazzan⁴, Chengyuan Wu¹, Qianhong Wu², and Feroze B. Mohamed^3
1Neurosurgery, Thomas Jefferson University Hospital, Philadelphia, PA, United States, ²Mechanical Engineering, Villanova University, Villanova, PA, United States, ³Radiology, Thomas Jefferson University Hospital, Philadelphia, PA, United States, ⁴Marcus Institute of Integrative Health, Villanova, PA, United States

Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Currently, non-invasive and longitudinal assessment in TBI is still limited. In the current study, we applied an advanced hybrid diffusion imaging sequence (HYDI) to capture both diffusion tensor imaging and neurite orientation dispersion and density imaging to develop more sensitive biomarkers associated with longitudinal outcomes after TBI. We both contrasting and complementary correlates between diffusion metrics and clinical outcomes, suggesting HYDI to have potential clinical impact for treatment monitoring after TBI.

Martins Otikovs¹, Debbie Anaby², Shai Shrot², Noam Nissan², and Lucio Frydman^1,3
1Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel, ²Sheba Medical Center, Ramat Gan, Israel, ³Azrieli National Center for Brain Imaging, Weizmann Institute of Science, Rehovot, Israel

Cholesteatomas are destructive lesions growing in the middle ear, in need of periodic assessments. Diffusion weighted imaging (DWI) at 3T provides clear contrast of these growths, facilitating their detection. However, the close presence of air-tissue interfaces within the ear channel results in geometric distortions that have led to adoption of non-EPI based methods for these high field evaluations. Herein we present results from initial DWI experiments performed for imaging cholesteatomas, which point out the value of Spatiotemporal Encoding (SPEN) DWI methods as promising alternatives to retrieve high-contrast, high-definition images.

Ahmed Radwan^1,2, Louise Emsell^1,2,3,4, Evy Cleeren⁵, Silvia Kovacs⁶, Anais Van Hoylandt⁵, Ronald Peeters⁶, Steven De Vleeschouwer^2,5,7, Tom Theys^2,5,7, Patrick Dupont^2,8, and Stefan Sunaert^1,2,6
1Imaging and pathology, Translational MRI, KU Leuven, Leuven, Belgium, ²Department of Neurosciences, KU Leuven, Leuven Brain Institute, Leuven, Belgium, ³Department of Neurosciences, Neuropsychiatry, KU Leuven, Leuven, Belgium, ⁴Geriatric Psychiatry, University Psychiatric Center (UPC) - Leuven, Leuven, Belgium, ⁵Department of Neurosurgery, University Hospitals Leuven, Leuven, Belgium, ⁶Department of Radiology, University Hospitals Leuven, Leuven, Belgium, ⁷Department of Neurosciences, Research Group Experimental Neurosurgery and Neuroanatomy, KU Leuven, Leuven, Belgium, ⁸Department of Neurosciences, Laboratory for cognitive neurology, KU Leuven, Leuven, Belgium

Accurate presurgical brain mapping enables preoperative risk assessment and intraoperative guidance to minimize postoperative deficits. Here we compare mapping accuracy of task-based fMRI (tbfMRI), BOLD and Functionnectome resting state fMRI (rsfMRI), DTI and constrained spherical deconvolution (CSD)-based tractography in 21 preoperative neurosurgical patients using intraoperative electrical stimulation (DES) as the ground truth for functional mapping. Accuracy was estimated based on minimum distance between MRI-based mapping and positive DES coordinates. We report that CSD outperforms DTI, and rsfMRI performs similarly to tbfMRI using DES. This demonstrates the potential benefits of using CSD and rsfMRI in clinical practice.

Azadeh Tabari^1,2, Min Lang^1,2, Daniel Polak^3,4, Daniel Nicolas Splitthoff⁴, Bryan Clifford⁵, Wei-Ching Lo⁵, Lawrence L. Wald^2,3,6, Stephen Cauley^2,3, Otto Rapalino^1,2, Pamela Schaefer^1,2, John Conklin^1,2,3, and Susie Y. Huang^1,2,3,6
1Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, ²Harvard Medical School, Boston, MA, United States, ³A. A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States, ⁴Siemens Healthcare GmbH, Erlangen, Germany, ⁵Siemens Medical Solutions, Malvern, PA, United States, ⁶Harvard-MIT Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States

Patient motion can degrade diagnostic image quality to the point that scans must be re-acquired, or patients called back. In this work, we performed a systematic clinical evaluation of SAMER, a highly efficient retrospective motion mitigation approach. 62 patients from emergency and inpatient care settings were scanned at 3T, and 14 cases were identified with a range of patient motion. Two neuro-radiologists performed blinded review of the images before and after motion correction, rating the images for motion severity. In 13 of the 14 cases, reduced motion severity and improved visualization of anatomy/pathology was obtained after SAMER motion mitigation.

Parimal Pravin Joshi¹, Yi Zhang^2,3, Xirui Pravin Hou², Cuimei Xu², Paul Bottomley², Hanzhang Lu², and Peiying Liu^1
1Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, United States, ²Department of Radiology, Johns Hopkins University School of medicine, Baltimore, MD, United States, ³Department of Biomedical Engineering, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China

Cerebrovascular reactivity (CVR) is typically measured with hypercapnic challenges, which require considerable subject cooperation. Recent CVR mapping approaches using resting-state BOLD data are promising, but their sensitivity is low in subjects with minimal spontaneous changes in breathing pattern. Performed in conjunction with resting-state BOLD scans, intermittent breath modulation enhances variations in breathing pattern while requiring minimal subject compliance, and is a promising tool for CVR mapping without gas inhalation. Here we conducted simultaneous fMRI-EEG experiments to investigate origins of the global BOLD signal fluctuations during intermittent breath modulation, to verify the validity of this new approach.