1
|
Ali HT, Sula I, AbuHamdia A, Elejla SA, Elrefaey A, Hamdar H, Elfil M. Nervous System Response to Neurotrauma: A Narrative Review of Cerebrovascular and Cellular Changes After Neurotrauma. J Mol Neurosci 2024; 74:22. [PMID: 38367075 PMCID: PMC10874332 DOI: 10.1007/s12031-024-02193-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 01/22/2024] [Indexed: 02/19/2024]
Abstract
Neurotrauma is a significant cause of morbidity and mortality worldwide. For instance, traumatic brain injury (TBI) causes more than 30% of all injury-related deaths in the USA annually. The underlying cause and clinical sequela vary among cases. Patients are liable to both acute and chronic changes in the nervous system after such a type of injury. Cerebrovascular disruption has the most common and serious effect in such cases because cerebrovascular autoregulation, which is one of the main determinants of cerebral perfusion pressure, can be effaced in brain injuries even in the absence of evident vascular injury. Disruption of the blood-brain barrier regulatory function may also ensue whether due to direct injury to its structure or metabolic changes. Furthermore, the autonomic nervous system (ANS) can be affected leading to sympathetic hyperactivity in many patients. On a cellular scale, the neuroinflammatory cascade medicated by the glial cells gets triggered in response to TBI. Nevertheless, cellular and molecular reactions involved in cerebrovascular repair are not fully understood yet. Most studies were done on animals with many drawbacks in interpreting results. Therefore, future studies including human subjects are necessarily needed. This review will be of relevance to clinicians and researchers interested in understanding the underlying mechanisms in neurotrauma cases and the development of proper therapies as well as those with a general interest in the neurotrauma field.
Collapse
Affiliation(s)
| | - Idris Sula
- College of Medicine, Sulaiman Al Rajhi University, Al Bukayriyah, Al Qassim, Saudi Arabia
| | - Abrar AbuHamdia
- Department of Medical Laboratory Science, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine
| | | | | | - Hiba Hamdar
- Medical Learning Skills Academy, Beirut, Lebanon
- Medical University of Plovdiv, Plovdiv, Bulgaria
| | - Mohamed Elfil
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
| |
Collapse
|
2
|
Anderson ED, Talukdar T, Goodwin G, Di Pietro V, Yakoub KM, Zwilling CE, Davies D, Belli A, Barbey AK. Assessing blood oxygen level-dependent signal variability as a biomarker of brain injury in sport-related concussion. Brain Commun 2023; 5:fcad215. [PMID: 37649639 PMCID: PMC10465085 DOI: 10.1093/braincomms/fcad215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 07/02/2023] [Accepted: 08/10/2023] [Indexed: 09/01/2023] Open
Abstract
Mild traumatic brain injury is a complex neurological disorder of significant concern among athletes who play contact sports. Athletes who sustain sport-related concussion typically undergo physical examination and neurocognitive evaluation to determine injury severity and return-to-play status. However, traumatic disruption to neurometabolic processes can occur with minimal detectable anatomic pathology or neurocognitive alteration, increasing the risk that athletes may be cleared for return-to-play during a vulnerable period and receive a repetitive injury. This underscores the need for sensitive functional neuroimaging methods to detect altered cerebral physiology in concussed athletes. The present study compared the efficacy of Immediate Post-concussion Assessment and Cognitive Testing composite scores and whole-brain measures of blood oxygen level-dependent signal variability for classifying concussion status and predicting concussion symptomatology in healthy, concussed and repetitively concussed athletes, assessing blood oxygen level-dependent signal variability as a potential diagnostic tool for characterizing functional alterations to cerebral physiology and assisting in the detection of sport-related concussion. We observed significant differences in regional blood oxygen level-dependent signal variability measures for concussed athletes but did not observe significant differences in Immediate Post-concussion Assessment and Cognitive Testing scores of concussed athletes. We further demonstrate that incorporating measures of functional brain alteration alongside Immediate Post-concussion Assessment and Cognitive Testing scores enhances the sensitivity and specificity of supervised random forest machine learning methods when classifying and predicting concussion status and post-concussion symptoms, suggesting that alterations to cerebrovascular status characterize unique variance that may aid in the detection of sport-related concussion and repetitive mild traumatic brain injury. These results indicate that altered blood oxygen level-dependent variability holds promise as a novel neurobiological marker for detecting alterations in cerebral perfusion and neuronal functioning in sport-related concussion, motivating future research to establish and validate clinical assessment protocols that can incorporate advanced neuroimaging methods to characterize altered cerebral physiology following mild traumatic brain injury.
Collapse
Affiliation(s)
- Evan D Anderson
- Decision Neuroscience Laboratory, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
- Air Force Research Laboratory, Wright-Patterson AFB, OH 45433, USA
| | - Tanveer Talukdar
- Decision Neuroscience Laboratory, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Grace Goodwin
- Decision Neuroscience Laboratory, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
- Department of Psychology, University of Nevada, Las Vegas, NV 89557, USA
| | - Valentina Di Pietro
- Decision Neuroscience Laboratory, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
- Neurotrauma and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
- NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham NHS Foundation Trust, Birmingham B15 2TH, UK
| | - Kamal M Yakoub
- Neurotrauma and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
- NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham NHS Foundation Trust, Birmingham B15 2TH, UK
| | - Christopher E Zwilling
- Decision Neuroscience Laboratory, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - David Davies
- Neurotrauma and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
- NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham NHS Foundation Trust, Birmingham B15 2TH, UK
| | - Antonio Belli
- Neurotrauma and Ophthalmology Research Group, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
- NIHR Surgical Reconstruction and Microbiology Research Centre, University Hospitals Birmingham NHS Foundation Trust, Birmingham B15 2TH, UK
| | - Aron K Barbey
- Decision Neuroscience Laboratory, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
- Department of Psychology, University of Illinois, Urbana, IL 61801, USA
- Department of Bioengineering, University of Illinois, Urbana, IL 61801, USA
- Center for Brain, Biology, and Behavior, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
| |
Collapse
|
3
|
Kawoos U, Abutarboush R, Zarriello S, Qadri A, Ahlers ST, McCarron RM, Chavko M. N-acetylcysteine Amide Ameliorates Blast-Induced Changes in Blood-Brain Barrier Integrity in Rats. Front Neurol 2019; 10:650. [PMID: 31297080 PMCID: PMC6607624 DOI: 10.3389/fneur.2019.00650] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 06/04/2019] [Indexed: 12/31/2022] Open
Abstract
Traumatic brain injury resulting from exposure to blast overpressure (BOP) is associated with neuropathology including impairment of the blood-brain barrier (BBB). This study examined the effects of repeated exposure to primary BOP and post-blast treatment with an antioxidant, N-acetylcysteine amide (NACA) on the integrity of BBB. Anesthetized rats were exposed to three 110 kPa BOPs separated by 0.5 h. BBB integrity was examined in vivo via a cranial window allowing imaging of pial microcirculation by intravital microscopy. Tetramethylrhodamine isothiocyanate Dextran (TRITC-Dextran, mw = 40 kDa or 150 kDa) was injected intravenously 2.5 h after the first BOP exposure and the leakage of TRITC-Dextran from pial microvessels into the brain parenchyma was assessed. The animals were randomized into 6 groups (n = 5/group): four groups received 40 kDa TRITC-Dextran (BOP-40, sham-40, BOP-40 NACA, and sham-40 NACA), and two groups received 150 kDa TRITC-Dextran (BOP-150 and sham-150). NACA treated groups were administered NACA 2 h after the first BOP exposure. The rate of TRITC-Dextran leakage was significantly higher in BOP-40 than in sham-40 group. NACA treatment significantly reduced TRITC-Dextran leakage in BOP-40 NACA group and sham-40 NACA group presented the least amount of leakage. The rate of leakage in BOP-150 and sham-150 groups was comparable to sham-40 NACA and thus these groups were not assessed for the effects of NACA. Collectively, these data suggest that BBB integrity is compromised following BOP exposure and that NACA treatment at a single dose may significantly protect against blast-induced BBB breakdown.
Collapse
Affiliation(s)
- Usmah Kawoos
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States.,Department of Neurotrauma, Naval Medical Research Center, Silver Spring, MD, United States
| | - Rania Abutarboush
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States.,Department of Neurotrauma, Naval Medical Research Center, Silver Spring, MD, United States
| | - Sydney Zarriello
- Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Aasheen Qadri
- Department of Biology, University of Maryland, College Park, MD, United States
| | - Stephen T Ahlers
- Department of Neurotrauma, Naval Medical Research Center, Silver Spring, MD, United States.,Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Richard M McCarron
- Department of Neurotrauma, Naval Medical Research Center, Silver Spring, MD, United States.,Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Mikulas Chavko
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States.,Department of Neurotrauma, Naval Medical Research Center, Silver Spring, MD, United States
| |
Collapse
|
4
|
Luo MY, Guo ZN, Qu Y, Zhang P, Wang Z, Jin H, Ma HY, Lv S, Sun X, Yang Y. Compromised Dynamic Cerebral Autoregulation in Patients With Depression. Front Psychiatry 2019; 10:373. [PMID: 31258489 PMCID: PMC6587060 DOI: 10.3389/fpsyt.2019.00373] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Accepted: 05/13/2019] [Indexed: 01/18/2023] Open
Abstract
Background: Patients with depression tend to have various comorbid neurological symptoms, but the mechanisms remain unclear. The purpose of this study was to analyze the characteristics of dynamic cerebral autoregulation in depressed patients. Methods: Patients (aged ≥ 18 years) who were diagnosed with depression [17-item Hamilton Depression Rating Scale (HAMD) > 17] or suspected of depression (HAMD > 7) were enrolled in this study. Medically healthy volunteers were recruited as controls. The subjects also received the 7-item HAMD. We simultaneously recorded noninvasive continuous arterial blood pressure and bilateral middle cerebral artery blood flow velocity from each subject. Cerebral autoregulation was assessed by analyzing the phase difference using transfer function analysis. Results: This study enrolled 54 patients with suspected depression, 45 patients with depression, and 48 healthy volunteers. The mean phase difference values were significantly lower in the patients with depression (F = 9.071, P < 0.001). In the multiple regression analysis, depression was negatively correlated with the phase difference values. Conclusions: Dynamic cerebral autoregulation was compromised in patients with depression and negatively correlated with the depression score. Improving dynamic cerebral autoregulation may be a potential therapeutic method for treating the neurological symptoms of depression.
Collapse
Affiliation(s)
- Ming-Ya Luo
- Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Zhen-Ni Guo
- Clinical Trial and Research Center for Stroke, Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Yang Qu
- Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Peng Zhang
- Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Zan Wang
- Clinical Trial and Research Center for Stroke, Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Hang Jin
- Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Hong-Yin Ma
- Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Shan Lv
- Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Xin Sun
- Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| | - Yi Yang
- Department of Neurology, First Hospital of Jilin University, Chang Chun, China
| |
Collapse
|
5
|
Abstract
This article reviews possible ways that traumatic brain injury (TBI) can induce migraine-type post-traumatic headaches (PTHs) in children, adults, civilians, and military personnel. Several cerebral alterations resulting from TBI can foster the development of PTH, including neuroinflammation that can activate neural systems associated with migraine. TBI can also compromise the intrinsic pain modulation system and this would increase the level of perceived pain associated with PTH. Depression and anxiety disorders, especially post-traumatic stress disorder (PTSD), are associated with TBI and these psychological conditions can directly intensify PTH. Additionally, depression and PTSD alter sleep and this will increase headache severity and foster the genesis of PTH. This article also reviews the anatomic loci of injury associated with TBI and notes the overlap between areas of injury associated with TBI and PTSD.
Collapse
|
6
|
Jullienne A, Obenaus A, Ichkova A, Savona-Baron C, Pearce WJ, Badaut J. Chronic cerebrovascular dysfunction after traumatic brain injury. J Neurosci Res 2016; 94:609-22. [PMID: 27117494 PMCID: PMC5415378 DOI: 10.1002/jnr.23732] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 02/11/2016] [Accepted: 02/28/2016] [Indexed: 12/12/2022]
Abstract
Traumatic brain injuries (TBI) often involve vascular dysfunction that leads to long-term alterations in physiological and cognitive functions of the brain. Indeed, all the cells that form blood vessels and that are involved in maintaining their proper function can be altered by TBI. This Review focuses on the different types of cerebrovascular dysfunction that occur after TBI, including cerebral blood flow alterations, autoregulation impairments, subarachnoid hemorrhage, vasospasms, blood-brain barrier disruption, and edema formation. We also discuss the mechanisms that mediate these dysfunctions, focusing on the cellular components of cerebral blood vessels (endothelial cells, smooth muscle cells, astrocytes, pericytes, perivascular nerves) and their known and potential roles in the secondary injury cascade. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Amandine Jullienne
- Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, California
| | - Andre Obenaus
- Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, California
- Department of Physiology, Loma Linda University School of Medicine, Loma Linda, California
- Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, University of California Riverside, Riverside, California
| | | | | | - William J Pearce
- Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California
| | - Jerome Badaut
- Department of Physiology, Loma Linda University School of Medicine, Loma Linda, California
- CNRS UMR5287, University of Bordeaux, Bordeaux, France
| |
Collapse
|
7
|
Logsdon AF, Lucke-Wold BP, Turner RC, Huber JD, Rosen CL, Simpkins JW. Role of Microvascular Disruption in Brain Damage from Traumatic Brain Injury. Compr Physiol 2015; 5:1147-60. [PMID: 26140712 PMCID: PMC4573402 DOI: 10.1002/cphy.c140057] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Traumatic brain injury (TBI) is acquired from an external force, which can inflict devastating effects to the brain vasculature and neighboring neuronal cells. Disruption of vasculature is a primary effect that can lead to a host of secondary injury cascades. The primary effects of TBI are rapidly occurring while secondary effects can be activated at later time points and may be more amenable to targeting. Primary effects of TBI include diffuse axonal shearing, changes in blood-brain barrier (BBB) permeability, and brain contusions. These mechanical events, especially changes to the BBB, can induce calcium perturbations within brain cells producing secondary effects, which include cellular stress, inflammation, and apoptosis. These secondary effects can be potentially targeted to preserve the tissue surviving the initial impact of TBI. In the past, TBI research had focused on neurons without any regard for glial cells and the cerebrovasculature. Now a greater emphasis is being placed on the vasculature and the neurovascular unit following TBI. A paradigm shift in the importance of the vascular response to injury has opened new avenues of drug-treatment strategies for TBI. However, a connection between the vascular response to TBI and the development of chronic disease has yet to be elucidated. Long-term cognitive deficits are common amongst those sustaining severe or multiple mild TBIs. Understanding the mechanisms of cellular responses following TBI is important to prevent the development of neuropsychiatric symptoms. With appropriate intervention following TBI, the vascular network can perhaps be maintained and the cellular repair process possibly improved to aid in the recovery of cellular homeostasis.
Collapse
Affiliation(s)
- Aric F Logsdon
- Department of Pharmaceutical Sciences, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - Brandon P Lucke-Wold
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - Ryan C Turner
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - Jason D Huber
- Department of Pharmaceutical Sciences, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - Charles L Rosen
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - James W Simpkins
- Department of Physiology and Pharmacology, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| |
Collapse
|
8
|
Badaut J, Bix GJ. Vascular neural network phenotypic transformation after traumatic injury: potential role in long-term sequelae. Transl Stroke Res 2013; 5:394-406. [PMID: 24323723 DOI: 10.1007/s12975-013-0304-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 10/23/2013] [Accepted: 10/24/2013] [Indexed: 01/11/2023]
Abstract
The classical neurovascular unit (NVU), composed primarily of endothelium, astrocytes, and neurons, could be expanded to include smooth muscle and perivascular nerves present in both the up- and downstream feeding blood vessels (arteries and veins). The extended NVU, which can be defined as the vascular neural network (VNN), may represent a new physiological unit to consider for therapeutic development in stroke, traumatic brain injury, and other brain disorders (Zhang et al., Nat Rev Neurol 8(12):711-716, 2012). This review is focused on traumatic brain injury and resultant post-traumatic changes in cerebral blood flow, smooth muscle cells, matrix, blood-brain barrier structures and function, and the association of these changes with cognitive outcomes as described in clinical and experimental reports. We suggest that studies characterizing TBI outcomes should increase their focus on changes to the VNN, as this may yield meaningful therapeutic targets to resolve posttraumatic dysfunction.
Collapse
Affiliation(s)
- J Badaut
- Department of Pediatrics, Loma Linda University School of Medicine, Coleman Pavilion, Room A1120, 11175 Campus Street, Loma Linda, CA, 92354, USA,
| | | |
Collapse
|
9
|
Bigler ED. Neuroimaging biomarkers in mild traumatic brain injury (mTBI). Neuropsychol Rev 2013; 23:169-209. [PMID: 23974873 DOI: 10.1007/s11065-013-9237-2] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 08/07/2013] [Indexed: 12/14/2022]
Abstract
Reviewed herein are contemporary neuroimaging methods that detect abnormalities associated with mild traumatic brain injury (mTBI). Despite advances in demonstrating underlying neuropathology in a subset of individuals who sustain mTBI, considerable disagreement persists in neuropsychology about mTBI outcome and metrics for evaluation. This review outlines a thesis for the select use of sensitive neuroimaging methods as potential biomarkers of brain injury recognizing that the majority of individuals who sustain an mTBI recover without neuroimaging signs or neuropsychological sequelae detected with methods currently applied. Magnetic resonance imaging (MRI) provides several measures that could serve as mTBI biomarkers including the detection of hemosiderin and white matter abnormalities, assessment of white matter integrity derived from diffusion tensor imaging (DTI), and quantitative measures that directly assess neuroanatomy. Improved prediction of neuropsychological outcomes in mTBI may be achieved with the use of targeted neuroimaging markers.
Collapse
Affiliation(s)
- Erin D Bigler
- Department of Psychology, Brigham Young University, 1001 SWKT, Provo, UT 84602, USA.
| |
Collapse
|
10
|
Metting Z, Cerliani L, Rödiger LA, van der Naalt J. Pathophysiological concepts in mild traumatic brain injury: diffusion tensor imaging related to acute perfusion CT imaging. PLoS One 2013; 8:e64461. [PMID: 23704986 PMCID: PMC3660324 DOI: 10.1371/journal.pone.0064461] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Accepted: 04/12/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND A subgroup of patients with mild traumatic brain injury (TBI) experiences residual symptoms interfering with their return to work. The pathophysiological substrate of the suboptimal outcome in these patients is a source of debate. OBJECTIVE To provide greater insight into the pathophysiological mechanisms of mild TBI. METHODS Diffusion tensor imaging (DTI) was performed during follow-up of 18 patients with mild TBI and compared with healthy control subjects. DTI data of the patient group were also compared with perfusion CT imaging in the acute phase of injury. RESULTS In patients with mild TBI, a trend was observed for a decreased fractional anisotropy (FA) in widespread bilateral frontal white matter areas with increased mean diffusivity (MD) in the parieto-temporal regions, compared to healthy control subjects. Cerebral blood volume (CBV) correlated significantly with FA in several white matter tracts including the corpus callosum, the internal capsule, the inferior fronto-occipital fascicle, the corticospinal tract, the superior and the inferior longitudinal fascicle. CONCLUSION In mild TBI with normal conventional imaging significant associations between cerebral perfusion in the acute phase of injury and DTI analyses in the chronic phase of injury were discerned. The pathophysiological concept of these findings is being outlined.
Collapse
Affiliation(s)
- Zwany Metting
- Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands.
| | | | | | | |
Collapse
|
11
|
Mayer AR, Mannell MV, Ling J, Gasparovic C, Yeo RA. Functional connectivity in mild traumatic brain injury. Hum Brain Mapp 2011; 32:1825-35. [PMID: 21259381 DOI: 10.1002/hbm.21151] [Citation(s) in RCA: 351] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 07/13/2010] [Accepted: 07/29/2010] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVES Research suggests that the majority of mild traumatic brain injury (mTBI) patients exhibit both cognitive and emotional dysfunction within the first weeks of injury, followed by symptom resolution 3-6 months postinjury. The neuronal correlates of said dysfunction are difficult to detect with standard clinical neuroimaging, complicating differential diagnosis and early identification of patients who may not recover. This study examined whether resting state functional magnetic resonance imaging (fMRI) provides objective markers of injury and predicts cognitive, emotional, and somatic complaints in mTBI patients semiacutely (<3 weeks postinjury) and in late recovery (3-5 month) phases. METHODS Twenty-seven semiacute mTBI patients and 26 gender, age, and education-matched controls were studied. Fifteen of 27 patients returned for a follow-up visit 3-5 months postinjury. The main dependent variables were spontaneous fluctuations (temporal correlation) in the default-mode (DMN) and fronto-parietal task-related networks as measured by fMRI. RESULTS Significant differences in self-reported cognitive, emotional, and somatic complaints were observed (all P < 0.05), despite normal clinical (T1 and T2) imaging and neuropsychological testing results. Mild TBI patients demonstrated decreased functional connectivity within the DMN and hyper-connectivity between the DMN and lateral prefrontal cortex. Measures of functional connectivity exhibited high levels of sensitivity and specificity for patient classification and predicted cognitive complaints in the semi-acute injury stage. However, no changes in functional connectivity were observed across a 4-month recovery period. CONCLUSIONS Abnormal connectivity between the DMN and frontal cortex may provide objective biomarkers of mTBI and underlie cognitive impairment.
Collapse
Affiliation(s)
- Andrew R Mayer
- The Mind Research Network, Albuquerque, New Mexico 87106, USA.
| | | | | | | | | |
Collapse
|
12
|
Mayer AR, Mannell MV, Ling J, Elgie R, Gasparovic C, Phillips JP, Doezema D, Yeo RA. Auditory orienting and inhibition of return in mild traumatic brain injury: a FMRI study. Hum Brain Mapp 2010; 30:4152-66. [PMID: 19554558 DOI: 10.1002/hbm.20836] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The semiacute phase of mild traumatic brain injury (mTBI) is associated with deficits in the cognitive domains of attention, memory, and executive function, which previous work suggests may be related to a specific deficit in disengaging attentional focus. However, to date, there have only been a few studies that have employed dynamic imaging techniques to investigate the potential neurological basis of these cognitive deficits during the semiacute stage of injury. Therefore, event-related functional magnetic resonance imaging was used to investigate the neurological correlates of attentional dysfunction in a clinically homogeneous sample of 16 patients with mTBI during the semiacute phase of injury (<3 weeks). Behaviorally, patients with mTBI exhibited deficits in disengaging and reorienting auditory attention following invalid cues as well as a failure to inhibit attentional allocation to a cued spatial location compared to a group of matched controls. Accordingly, patients with mTBI also exhibited hypoactivation within thalamus, striatum, midbrain nuclei, and cerebellum across all trials as well as hypoactivation in the right posterior parietal cortex, presupplementary motor area, bilateral frontal eye fields, and right ventrolateral prefrontal cortex during attentional disengagement. Finally, the hemodynamic response within several regions of the attentional network predicted response times better for controls than for patients with mTBI. These objective neurological findings represent a potential biomarker for the behavioral deficits in spatial attention that characterize the initial recovery phase of mTBI.
Collapse
Affiliation(s)
- Andrew R Mayer
- The Mind Research Network, Albuquerque, New Mexico 87106, USA.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Neuropsychology and clinical neuroscience of persistent post-concussive syndrome. J Int Neuropsychol Soc 2008; 14:1-22. [PMID: 18078527 DOI: 10.1017/s135561770808017x] [Citation(s) in RCA: 262] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Revised: 08/16/2007] [Accepted: 08/16/2007] [Indexed: 01/17/2023]
Abstract
On the mild end of the acquired brain injury spectrum, the terms concussion and mild traumatic brain injury (mTBI) have been used interchangeably, where persistent post-concussive syndrome (PPCS) has been a label given when symptoms persist for more than three months post-concussion. Whereas a brief history of concussion research is overviewed, the focus of this review is on the current status of PPCS as a clinical entity from the perspective of recent advances in the biomechanical modeling of concussion in human and animal studies, particularly directed at a better understanding of the neuropathology associated with concussion. These studies implicate common regions of injury, including the upper brainstem, base of the frontal lobe, hypothalamic-pituitary axis, medial temporal lobe, fornix, and corpus callosum. Limitations of current neuropsychological techniques for the clinical assessment of memory and executive function are explored and recommendations for improved research designs offered, that may enhance the study of long-term neuropsychological sequelae of concussion.
Collapse
|
14
|
Rafols JA, Morgan R, Kallakuri S, Kreipke CW. Extent of nerve cell injury in Marmarou's model compared to other brain trauma models. Neurol Res 2007; 29:348-55. [PMID: 17626729 DOI: 10.1179/016164107x204657] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
OBJECTIVES We sought to determine the extent of nerve cell injury in the Marmarou's acceleration impact model of diffuse brain injury. METHODS Sensitive markers for cell injury including immunostaining for beta-amyloid precursor protein (beta-APP, a marker for diffuse axonal injury, DAI), Fluoro-Jade (FJ) histochemistry and electron microscopy (EM) were used in sham-operated and traumatized brains. RESULTS APP immunostaining confirmed and extended previous findings of DAI in association and subcortical fiber systems in the white matter after injury. Increasing FJ labeling of neurons in layers II-III of sensorimotor cortex (smCx) from 4 to 48 hours after trauma and scattered labeled cells were found in the lower cortical layers. EM confirmed the presence of dystrophic pyramidal neurons in layers II-III of smCx 24 and 48 hours post-trauma. DISCUSSION Taken together, the data revealed significant nerve cell injury without apparent cell death in this model.
Collapse
Affiliation(s)
- José A Rafols
- Department of Anatomy and Cell Biology, Scott Hall, Room No. 9312, Wayne State University School of Medicine, 540 E. Canfield, Detroit, MI 48201, USA.
| | | | | | | |
Collapse
|
15
|
Ohlsson M, Svensson M. Early decompression of the injured optic nerve reduces axonal degeneration and improves functional outcome in the adult rat. Exp Brain Res 2006; 179:121-30. [PMID: 17103208 DOI: 10.1007/s00221-006-0775-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Accepted: 10/23/2006] [Indexed: 11/30/2022]
Abstract
The putative beneficial role of an early decompression of injured CNS tissue following trauma remains controversial. In this study, we approach this scientific query using a standardized injury of the optic nerve in adult rats. Adult Sprague-Dawley rats were subjected to a standardized optic nerve constriction injury by applying a loose ligature around the nerve for 5 min, 1, 6 or 24 h. All animals were sacrificed at 28 dpi. Viable axons distal to the injury were quantified using semithin sections, and regenerative fibers were studied using antisera to neurofilament and GAP43. Axonal degeneration and glial scar development were analyzed using Fluoro-Jade staining and anti-GFAP, respectively. Visual function was studied with visual evoked potentials (VEP). No significant differences were observed between 1 and 6 h of optic nerve compression. However, the number of viable axons analyzed with neurofilament and on semithin sections, decreased significantly between 6 and 24 h, paralleled by an increase in Fluoro-Jade labeled axonal debris (P < 0.001). GFAP-IR density was significantly higher (P < 0.001) in the 24 h compression group in comparison to 6 h. VEP showed preserved, but impaired visual function in animals subjected to compression up to 6 h, compared to an abolished cortical response at 24 h. Regenerative GAP43-positive sprouts were occasionally found distal to the lesion in animals subjected to compression up to 6 h, but not at 24 h. These findings suggest that early optic nerve decompression within hours after the initial trauma is beneficial for functional outcome.
Collapse
Affiliation(s)
- Marcus Ohlsson
- Department of Clinical Neuroscience, Section of Neurosurgery, Karolinska Institutet, Karolinska Hospital, Solna, Stockholm 171 76, Sweden.
| | | |
Collapse
|