A5048584014- Advanced Neuroimaging Techniques and Applications
- Advanced MRI Techniques and Applications
- Traumatic Brain Injury Research
- Traumatic Brain Injury and Neurovascular Disturbances
- Bone and Joint Diseases
- Spinal Cord Injury Research
- Spinal Dysraphism and Malformations
- MRI in cancer diagnosis
- Cervical and Thoracic Myelopathy
- Spine and Intervertebral Disc Pathology
- Cerebral Palsy and Movement Disorders
- Spinal Fractures and Fixation Techniques
- Functional Brain Connectivity Studies
- Medical Imaging and Analysis
- Automotive and Human Injury Biomechanics
- Multiple Sclerosis Research Studies
- Fetal and Pediatric Neurological Disorders
- Glioma Diagnosis and Treatment
- NMR spectroscopy and applications
- Prenatal Substance Exposure Effects
- Medical Imaging Techniques and Applications
- Neurogenesis and neuroplasticity mechanisms
- Memory and Neural Mechanisms
- Cardiac Imaging and Diagnostics
- Neonatal and fetal brain pathology
Medical College of Wisconsin
2016-2025
Milwaukee VA Medical Center
2015-2025
Ontario Neurotrauma Foundation
2021
Marquette University
2017
Baylor College of Medicine
2017
University of Wisconsin–Madison
2017
National Institutes of Health
2009-2015
University of Alberta
2015
National Institute of Biomedical Imaging and Bioengineering
2014
Washington University in St. Louis
2005-2011
The dissociation between magnetic resonance imaging (MRI) and permanent disability in multiple sclerosis (MS), termed the clinicoradiological paradox, can primarily be attributed to lack of specificity conventional, relaxivity-based MRI measurements detecting axonal damage, primary pathological correlate long-term impairment MS. Diffusion tensor (DTI) has shown promise specifically damage demyelination MS its animal model, experimental autoimmune encephalomyelitis (EAE). To quantify DTI...
Diffusion tensor imaging is highly sensitive to the microstructural integrity of brain and has uncovered significant abnormalities following traumatic injury not appreciated through other methods. It hoped that this increased sensitivity will aid in detection prognostication patients with injury. However, pathological substrates such changes are poorly understood. Specifically, decreases fractional anisotropy derived from diffusion consistent axonal injury, myelin or both white matter...
Abstract Diffusion tensor imaging (DTI) has been widely applied to investigate injuries in the central nervous system (CNS) white matter (WM). However, underlying pathological correlates of diffusion changes have not adequately determined. In this study coregistration histological sections MR images and a pixel‐based receiver operating characteristic (ROC) analysis were used compare axial (λ ∥ ) radial ⟂ diffusivities derived from DTI markers axon (phosphorylated neurofilament, SMI‐31)...
Abstract Functional neuroimaging studies of episodic memory retrieval generally measure brain activity while participants remember items encountered in the laboratory (“controlled condition”) or events from their own life (“open autobiographical condition”). Differences activation between these conditions may reflect differences processes, remoteness, emotional content, success, self-referential processing, visual/spatial memory, and recollection. To clarify nature differences, a functional...
Diffusion MRI is arguably the method of choice for characterizing white matter microstructure in vivo. Over typical duration diffusion encoding, displacement water molecules conveniently on a length scale similar to that underlying cellular structures. Moreover, are largely compartmentalized which enables biologically-inspired compartmental models characterize and quantify true biological microstructure. A plethora have been proposed. However, overparameterization mathematical fitting...
Diffusion-weighted MRI (DWI) is a sensitive and reliable marker of cerebral ischemia. Within minutes an ischemic event in the brain, microscopic motion water molecules measured with DWI, termed apparent diffusion coefficient (ADC), decreases within infarcted region. However, although change related to cell swelling, precise pathological mechanism remains elusive. We show that focal enlargement constriction, or beading, axons dendrites are sufficient substantially decrease ADC. first derived...
Abstract Recent studies have suggested that axonal damage, and not demyelination, is the primary cause of long‐term neurological impairment in multiple sclerosis its animal model, experimental autoimmune encephalomyelitis (EAE). The axial radial diffusivities derived from diffusion tensor imaging shown promise as non‐invasive surrogate markers damage respectively. In this study, vivo spinal cords mice with chronic EAE was performed to determine if diffusivity correlated disability assessed...
Noninvasive assessment of the progression axon damage is important for evaluating disease and developing neuroprotective interventions in multiple sclerosis patients. We examined thecellular responses correlated with diffusion tensor imaging-derivedaxial (λ∥) radial (λ⊥) diffusivity values throughout acute (4 weeks) chronic (12 stages demyelination after 6 weeks recovery using cuprizone corpus callosum model C57BL/6 Thy1-YFP-16 mice. The rostrocaudal pathological alterations enabled...
After central nervous system injury, inflammatory macrophages (M1) predominate over anti-inflammatory (M2). The temporal profile of M1/M2 phenotypes in and microglia after traumatic brain injury (TBI) rats is unknown. We subjected female to severe controlled cortical impact (CCI) examined the postinjury time course their brains. motor cortex (2.5 mm left laterally 1.0 anteriorly from bregma) anesthetized Wistar (ages 8 10 weeks; N = 72) underwent histologically moderate CCI with a 5-mm...
ORIGINAL RESEARCH article Front. Integr. Neurosci., 01 February 2013 | https://doi.org/10.3389/fnint.2013.00003
Accurate diagnosis of spinal cord injury (SCI) severity must be achieved before highly aggressive experimental therapies can tested responsibly in the early phases after trauma. These studies demonstrate for first time that axial diffusivity (λ||), derived from diffusion tensor imaging (DTI) within 3 h SCI, accurately predicts long-term locomotor behavioral recovery mice. Female C57BL/6 mice underwent sham laminectomy or graded contusive injuries at T9 vertebral level (5 groups, n = 8 each...
The incidence of traumatic brain injury (TBI) among military personnel is at its highest point in U.S. history. Experimental animal models blast have provided a wealth insight into injury. mechanisms neurotrauma caused by blast, however, are still under debate. Specifically, it unclear whether the shockwave absence head motion sufficient to induce trauma. In this study, consequences were investigated rat model primary TBI. Animals exposed shockwaves with peak overpressures either 100 or 450...
Diffusion-weighted imaging (DWI) of tissue water is a sensitive and specific indicator acute brain ischemia, where reductions the diffusion are observed acutely in stroke lesion core. Although these changes have been long attributed to cell swelling, precise nature biophysical mechanisms remains uncertain.The potential cause after was investigated using an advanced DWI technique, oscillating gradient spin-echo DWI, that enables much shorter times can improve specificity for alterations...
Functional magnetic resonance imaging (fMRI) studies have demonstrated alterations during task-induced brain activation in spinal cord injury (SCI) patients. The interruption to structural integrity of the and resultant disrupted flow bidirectional communication between might contribute observed dynamic reorganization (neural plasticity). However, effect SCI on resting-state connectivity patterns remains unclear. We undertook a prospective fMRI (rs-fMRI) study explore changes cortical...
Abstract In a companion paper by Cohen-Adad et al . we introduce the spine generic quantitative MRI protocol that provides valuable metrics for assessing spinal cord macrostructural and microstructural integrity. This was used to acquire single subject dataset across 19 centers multi-subject 42 (for total of 260 participants), spanning three main manufacturers: GE, Philips Siemens. Both datasets are publicly available via git-annex. Data were analysed using Spinal Cord Toolbox produce...
Abstract Multiple sclerosis (MS) is an autoimmune disease of the CNS characterized by disruption blood-brain barrier (BBB). This breach in immune privilege allows undeterred trafficking myelin-specific lymphocytes into where they induce demyelination. Although mechanism BBB compromise not known, chemokine CXCL12 has been implicated as a molecular component whose pattern expression specifically altered during MS and which correlates with severity. The inflammatory cytokine IL-1β recently...