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Suskauer SJ, Huisman TAGM. Neuroimaging in pediatric traumatic brain injury: current and future predictors of functional outcome. ACTA ACUST UNITED AC 2009; 15:117-23. [PMID: 19489082 DOI: 10.1002/ddrr.62] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Although neuroimaging has long played a role in the acute management of pediatric traumatic brain injury (TBI), until recently, its use as a tool for understanding and predicting long-term brain-behavior relationships after TBI has been limited by the relatively poor sensitivity of routine clinical imaging for detecting diffuse axonal injury (DAI). Newer magnetic resonance-based imaging techniques demonstrate improved sensitivity to DAI. Early research suggests that these techniques hold promise for identifying imaging predictors and correlates of chronic function, both globally and within specific neuropsychological domains. In this review, we describe the principles of new, advanced imaging techniques including diffusion weighted and diffusion tensor imaging, susceptibility weighted imaging, and (1)H-magnetic resonance spectroscopy. In addition, we summarize current research demonstrating their early success in establishing relationships between imaging measures and functional outcomes after TBI. With the ongoing research, these imaging techniques may allow earlier identification of possible chronic sequelae of tissue injury for each child with TBI, thereby facilitating efficacy and efficiency in delivering successful rehabilitation services.
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Affiliation(s)
- Stacy J Suskauer
- Department of Physical Medicine and Rehabilitation, Kennedy Krieger Institute, Johns Hopkins University School of Medicine, 707 North Broadway, Baltimore, MD 21205, USA.
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152
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Wozniak JR, Muetzel RL, Mueller BA, McGee CL, Freerks MA, Ward EE, Nelson ML, Chang PN, Lim KO. Microstructural corpus callosum anomalies in children with prenatal alcohol exposure: an extension of previous diffusion tensor imaging findings. Alcohol Clin Exp Res 2009; 33:1825-35. [PMID: 19645729 DOI: 10.1111/j.1530-0277.2009.01021.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Several studies have now shown corpus callosum abnormalities using diffusion tensor imaging (DTI) in children with fetal alcohol spectrum disorders (FASD) in comparison with nonexposed controls. The data suggest that posterior regions of the callosum may be disproportionately affected. The current study builds on previous efforts, including our own work, and moves beyond midline corpus callosum to probe major inter-hemispheric white matter pathways with an improved DTI tractographic method. This study also expands on our prior work by evaluating a larger sample and by incorporating children with a broader range of clinical effects including full-criteria fetal alcohol syndrome (FAS). METHODS Participants included 33 children with FASD (8 FAS, 23 partial FAS, 2 static encephalopathy) and 19 nonexposed controls between the ages of 10 and 17 years. Participants underwent DTI scans and intelligence testing. Groups (FASD vs. controls) were compared on fractional anisotropy (FA) and mean diffusivity (MD) in 6 white matter tracts projected through the corpus callosum. Exploratory analyses were also conducted examining the relationships between DTI measures in the corpus callosum and measures of intellectual functioning and facial dysmorphology. RESULTS In comparison with the control group, the FASD group had significantly lower FA in 3 posterior tracts of the corpus callosum: the posterior mid-body, the isthmus, and the splenium. A trend-level finding also suggested lower FA in the genu. Measures of white matter integrity and cognition were correlated and suggest some regional specificity, in that only posterior regions of the corpus callosum were associated with visual-perceptual skills. Correlations between measures of facial dysmorphology and posterior regions of the corpus callosum were nonsignificant. CONCLUSIONS Consistent with previous DTI studies, these results suggest that microstructural posterior corpus callosum abnormalities are present in children with prenatal alcohol exposure and cognitive impairment. These abnormalities are clinically relevant because they are associated with cognitive deficits and appear to provide evidence of abnormalities associated with prenatal alcohol exposure independent of dysmorphic features. As such, they may yield important diagnostic and prognostic information not provided by the traditional facial characteristics.
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153
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Kumar R, Husain M, Gupta RK, Hasan KM, Haris M, Agarwal AK, Pandey CM, Narayana PA. Serial changes in the white matter diffusion tensor imaging metrics in moderate traumatic brain injury and correlation with neuro-cognitive function. J Neurotrauma 2009; 26:481-95. [PMID: 19196176 DOI: 10.1089/neu.2008.0461] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Diffuse axonal injury (DAI) that follows traumatic brain injury (TBI) is thought to be a major contributor to neurocognitive dysfunction that sometimes follows TBI. Conventional magnetic resonance imaging (MRI), diffusion tensor imaging (DTI) and neuropsychological tests (NPT) were performed on 38 TBI patients [hemorrhagic DAI (H-DAI, n=8), non-hemorrhagic (Nh-DAI, n=7), with no apparent DAI on conventional MRI (NA-DAI, n=23)] with a Glasgow Coma Scale score ranging between 9 and 13. The fractional anisotropy (FA) and mean diffusivity (MD) were quantified from different regions of the corpus callosum (CC), and peri-ventricular white matter (PWM) within 5-14 days and 6 months following TBI. Patients in all three groups showed decreased FA in the anterior limb of the internal capsule (ALIC) and the posterior limb of the internal capsule (PLIC), while the genu of the CC showed a decrease in the H-DAI group during the early period following TBI that persisted 6 months later, which appeared to be consistent with axonopathy. In patients without abnormalities on conventional MRI and DTI in the initial phase, a significant decrease in FA and increase in MD were observed in a few regions of the CC at 6 months, which was suggestive of demyelination/gliosis. The changes in FA and MD in the CC and PWM at 6 months follow-up showed significant correlation with some of the NPT performed in the three groups. DTI demonstrates axonopathy in the acute stage, as well as at secondary stages, at 6 months post-injury in the CC and PWM in regions of normal-appearing white matter on conventional MRI.
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Affiliation(s)
- Raj Kumar
- Department of Neurosurgery, Chhatrapati Shahuji Maharaj Medical University, UP, India
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154
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Ciccia AH, Meulenbroek P, Turkstra LS. Adolescent Brain and Cognitive Developments: Implications for Clinical Assessment in Traumatic Brain Injury. TOPICS IN LANGUAGE DISORDERS 2009; 29:249-265. [PMID: 30220763 PMCID: PMC6135107 DOI: 10.1097/tld.0b013e3181b53211] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Adolescence is a time of significant physical, social, and emotional developments, accompanied by changes in cognitive and language skills. Underlying these are significant developments in brain structures and functions including changes in cortical and subcortical gray matter and white matter tracts. Among the brain regions that develop during adolescence are areas that are commonly damaged as a result of a traumatic brain injury (TBI). This paper summarizes major brain changes during adolescence and evidence linking maturation of these cognitive and language functions to brain development, placing consideration of both areas of development in the context of rehabilitation for adolescents with TBI.
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Affiliation(s)
- Angela Hein Ciccia
- Department of Communication Sciences, Case Western Reserve University, Cleveland, Ohio (Dr Ciccia); and Department of Communicative Disorders, University of Wisconsin-Madison (Mr Meulenbroek and Dr Turkstra)
| | - Peter Meulenbroek
- Department of Communication Sciences, Case Western Reserve University, Cleveland, Ohio (Dr Ciccia); and Department of Communicative Disorders, University of Wisconsin-Madison (Mr Meulenbroek and Dr Turkstra)
| | - Lyn S Turkstra
- Department of Communication Sciences, Case Western Reserve University, Cleveland, Ohio (Dr Ciccia); and Department of Communicative Disorders, University of Wisconsin-Madison (Mr Meulenbroek and Dr Turkstra)
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155
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Abstract
Emerging evidence suggests unique age-dependent responses following pediatric traumatic brain injury. The anesthesiologist plays a pivotal role in the acute treatment of the head-injured pediatric patient. This review provides important updates on the pathophysiology, diagnosis, and age-appropriate acute management of infants and children with severe traumatic brain injury. Areas of important clinical and basic science investigations germane to the anesthesiologist, such as the role of anesthetics and apoptosis in the developing brain, are discussed.
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Affiliation(s)
- Jimmy W Huh
- Critical Care and Pediatrics, Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, Critical Care Office, Philadelphia, PA 19104-4399, USA.
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156
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Tang PH, Lim CCT. Imaging of accidental paediatric head trauma. Pediatr Radiol 2009; 39:438-46. [PMID: 19125244 DOI: 10.1007/s00247-008-1083-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Accepted: 09/21/2008] [Indexed: 10/24/2022]
Abstract
Head trauma is the most common form of injury sustained in serious childhood trauma and remains one of the top three causes of death despite improved road planning and safety laws. CT remains the first-line investigation for paediatric head trauma, although MRI may be more sensitive at picking up the full extent of injuries and may be useful for prognosis. Follow-up imaging should be tailored to answer the specific clinical question and to look for possible complications.
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Affiliation(s)
- Phua Hwee Tang
- Department of Diagnostic Imaging, KK Women's and Children's Hospital, Singapore, Singapore.
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157
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Orrison WW, Hanson EH, Alamo T, Watson D, Sharma M, Perkins TG, Tandy RD. Traumatic Brain Injury: A Review and High-Field MRI Findings in 100 Unarmed Combatants Using a Literature-Based Checklist Approach. J Neurotrauma 2009; 26:689-701. [DOI: 10.1089/neu.2008.0636] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- William W. Orrison
- Nevada Imaging Centers, Las Vegas, Nevada
- Amigenics (Advanced Medical Imaging and Genetics), Inc., Las Vegas, Nevada
- Touro University Nevada College of Osteopathic Medicine, Henderson, Nevada
| | - Eric H. Hanson
- Amigenics (Advanced Medical Imaging and Genetics), Inc., Las Vegas, Nevada
- Touro University Nevada College of Osteopathic Medicine, Henderson, Nevada
| | | | - David Watson
- Nevada State Athletic Commission, Las Vegas, Nevada
| | - Mythri Sharma
- Touro University Nevada College of Osteopathic Medicine, Henderson, Nevada
| | | | - Richard D. Tandy
- Department of Kinesiology, University of Nevada, Las Vegas, Nevada
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158
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Galloway NR, Tong KA, Ashwal S, Oyoyo U, Obenaus A. Diffusion-weighted imaging improves outcome prediction in pediatric traumatic brain injury. J Neurotrauma 2009; 25:1153-62. [PMID: 18842104 DOI: 10.1089/neu.2007.0494] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Diffusion-weighted imaging (DWI) and consequent apparent diffusion coefficient (ADC) maps have been used for lesion detection and as a predictor of outcome in adults with traumatic brain injury (TBI), but few studies have been reported in children. We evaluated the role of DWI and ADC for outcome prediction after pediatric TBI (n=37 TBI; n=10 controls). Fifteen regions of interest (ROIs) were manually drawn on ADC maps that were grouped for analysis into peripheral gray matter, peripheral white matter, deep gray and white matter, and posterior fossa. All ROIs excluded areas that appeared abnormal on T2-weighted images (T2WI). Acute injury severity was measured using the Glasgow Coma Scale (GCS) score, and 6-12-month outcomes were assessed using the Pediatric Cerebral Performance Category Scale (PCPCS) score. Patients were categorized into five groups: (1) controls; (2) all TBI patients; (3) mild/moderate TBI with good outcomes; (4) severe TBI with good outcomes; and (5) severe TBI with poor outcomes. ADC values in the peripheral white matter were significantly reduced in children with severe TBI with poor outcomes (72.8+/-14.4x10(-3) mm2/sec) compared to those with severe TBI and good outcomes (82.5+/-3.8x10(-3) mm2/sec; p<0.05). We also found that the average total brain ADC value alone had the greatest ability to predict outcome and could correctly predict outcome in 84% of cases. Assessment of DWI and ADC values in pediatric TBI is useful in evaluating injury, particularly in brain regions that appear normal on conventional imaging. Early identification of children at high risk for poor outcome may assist in aggressive clinical management of pediatric TBI patients.
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Affiliation(s)
- Nicholas R Galloway
- Department of Radiation Medicine, Loma Linda University, Loma Linda, California 92354, USA
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159
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Kurowski B, Wade SL, Cecil KM, Walz NC, Yuan W, Rajagopal A, Holland SK. Correlation of diffusion tensor imaging with executive function measures after early childhood traumatic brain injury. J Pediatr Rehabil Med 2009; 2:273-83. [PMID: 21234279 PMCID: PMC3018823 DOI: 10.3233/prm-2009-0093] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Examine relationships of diffusion tensor imaging (DTI) fractional anisotropy (FA) to executive function (EF) and attention measures following early childhood (3-7 years) traumatic brain injury (TBI). DESIGN Exploratory correlation and comparison study. SETTING Children's hospital outpatient facilities. PARTICIPANTS 9 children with a history of TBI (age = 7.89 ± 1.00 years; Glasgow Coma Scale (GCS) = 10.11 ± 4.68) were compared to 12 children with OI (age = 7.51 ± 0.95). All children were at least 12 months post injury at time of evaluation. MAIN OUTCOME MEASURES FA in various regions of interest (ROI), EF and attention measures. RESULTS FA values primarily in the frontal white matter tracks correlated with EF measures. Separate tasks of inhibition and switching correlated significantly with FA in bilateral frontal lobes. Tasks combining both inhibition and switching correlated significantly with FA values in the left frontal lobe. Tasks of attention negatively correlated with FA values in the right frontal white matter and the superior longitudinal fasciculus. CONCLUSIONS Associations between late measurement of FA and EF measures following early childhood TBI suggest that persistent white matter changes, especially in the frontal white matter, may provide an index of EF deficits.
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Affiliation(s)
- Brad Kurowski
- Department of Pediatric Rehabilitation Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH,USA
| | - Shari L. Wade
- Department of Pediatric Rehabilitation Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH,USA
- Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Kim M. Cecil
- Department of Radiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Nicolay C. Walz
- Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Weihong Yuan
- Department of Radiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Akila Rajagopal
- Department of Radiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Scott K. Holland
- Department of Radiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
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160
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Diffusion tensor imaging in relation to cognitive and functional outcome of traumatic brain injury in children. J Head Trauma Rehabil 2008; 23:197-208. [PMID: 18650764 DOI: 10.1097/01.htr.0000327252.54128.7c] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To investigate the relation of white matter integrity using diffusion tensor imaging (DTI) to cognitive and functional outcome of moderate to severe traumatic brain injury (TBI) in children. DESIGN Prospective observational study of children who had sustained moderate to severe TBI and a comparison group of children who had sustained orthopedic injury (OI). PARTICIPANTS Thirty-two children who had sustained moderate to severe TBI and 36 children with OI were studied. METHODS Fiber tracking analysis of DTI acquired at 3-month postinjury and assessment of global outcome and cognitive function within 2 weeks of brain imaging. Global outcome was assessed using the Glasgow Outcome Scale and the Flanker task was used to measure cognitive processing speed and resistance to interference. RESULTS Fractional anisotropy and apparent diffusion coefficient values differentiated the groups and both cognitive and functional outcome measures were related to the DTI findings. Dissociations were present wherein the relation of Fractional anisotropy to cognitive performance differed between the TBI and OI groups. A DTI composite measure of white matter integrity was related to global outcome in the children with TBI. CONCLUSIONS DTI is sensitive to white matter injury at 3 months following moderate to severe TBI in children, including brain regions that appear normal on conventional magnetic resonance imaging. DTI measures reflecting diffusion of water parallel and perpendicular to white matter tracts as calculated by fiber tracking analysis are related to global outcome, cognitive processing speed, and speed of resolving interference in children with moderate to severe TBI. Longitudinal data are needed to determine whether these relations between DTI and neurobehavioral outcome of TBI in children persist at longer follow-up intervals.
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161
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Ewing-Cobbs L, Prasad MR, Swank P, Kramer L, Cox CS, Fletcher JM, Barnes M, Zhang X, Hasan KM. Arrested development and disrupted callosal microstructure following pediatric traumatic brain injury: relation to neurobehavioral outcomes. Neuroimage 2008; 42:1305-15. [PMID: 18655838 PMCID: PMC2615227 DOI: 10.1016/j.neuroimage.2008.06.031] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2008] [Revised: 06/13/2008] [Accepted: 06/24/2008] [Indexed: 11/29/2022] Open
Abstract
Chronic pediatric traumatic brain injury (TBI) is associated with significant and persistent neurobehavioral deficits. Using diffusion tensor imaging (DTI), we examined area, fractional anisotropy (FA), radial diffusion, and axial diffusion from six regions of the corpus callosum (CC) in 41 children and adolescents with TBI and 31 comparison children. Midsagittal cross-sectional area of the posterior body and isthmus was similar in younger children irrespective of injury status; however, increased area was evident in the older comparison children but was obviated in older children with TBI, suggesting arrested development. Similarly, age was correlated significantly with indices of tissue microstructure only for the comparison group. TBI was associated with significant reduction in FA and increased radial diffusivity in the posterior third of the CC and in the genu. The axial diffusivity did not differ by either age or group. Logistic regression analyses revealed that FA and radial diffusivity were equally sensitive to post-traumatic changes in 4 of 6 callosal regions; radial diffusivity was more sensitive for the rostral midbody and splenium. IQ, working memory, motor, and academic skills were correlated significantly with radial diffusion and/or FA from the isthmus and splenium only in the TBI group. Reduced size and microstructural changes in posterior callosal regions after TBI suggest arrested development, decreased organization, and disrupted myelination. Increased radial diffusivity was the most sensitive DTI-based surrogate marker of the extent of neuronal damage following TBI; FA was most strongly correlated with neuropsychological outcomes.
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Affiliation(s)
- Linda Ewing-Cobbs
- Department of Pediatrics, University of Texas-Houston Health Science Center at Houston, 77030, USA.
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162
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Taylor HG, Swartwout MD, Yeates KO, Walz NC, Stancin T, Wade SL. Traumatic brain injury in young children: postacute effects on cognitive and school readiness skills. J Int Neuropsychol Soc 2008; 14:734-45. [PMID: 18764969 PMCID: PMC2733858 DOI: 10.1017/s1355617708081150] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Previous studies have documented weaknesses in cognitive ability and early academic readiness in young children with traumatic brain injury (TBI). However, few of these studies have rigorously controlled for demographic characteristics, examined the effects of TBI severity on a wide range of skills, or explored moderating influences of environmental factors on outcomes. To meet these objectives, each of three groups of children with TBI (20 with severe, 64 with moderate, and 15 with mild) were compared with a group of 117 children with orthopedic injuries (OI group). The children were hospitalized for their injuries between 3 and 6 years of age and were assessed an average of 1 1/2 months post injury. Analysis revealed generalized weaknesses in cognitive and school readiness skills in the severe TBI group and less pervasive effects of moderate TBI. Indices of TBI severity predicted outcomes within the TBI sample and environmental factors moderated the effects of TBI on some measures. The findings document adverse effects of TBI in early childhood on postacute cognitive and school readiness skills and indicate that these effects are related to both injury severity and the family environment.
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Affiliation(s)
- H Gerry Taylor
- Division of Developmental and Behavioral Pediatrics and Pediatric Psychology, Department of Pediatrics, Case Western Reserve University and University Hospitals Case Medical Center, Cleveland, Ohio, USA.
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163
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Mädler B, Drabycz SA, Kolind SH, Whittall KP, MacKay AL. Is diffusion anisotropy an accurate monitor of myelination? Magn Reson Imaging 2008; 26:874-88. [PMID: 18524521 DOI: 10.1016/j.mri.2008.01.047] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Accepted: 01/14/2008] [Indexed: 11/16/2022]
Affiliation(s)
- Burkhard Mädler
- Department of Physics and Astronomy, University of British Columbia Hospital, Vancouver BC, Canada.
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164
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Hasan KM, Kamali A, Kramer LA, Papnicolaou AC, Fletcher JM, Ewing-Cobbs L. Diffusion tensor quantification of the human midsagittal corpus callosum subdivisions across the lifespan. Brain Res 2008; 1227:52-67. [PMID: 18598682 DOI: 10.1016/j.brainres.2008.06.030] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Revised: 06/08/2008] [Accepted: 06/10/2008] [Indexed: 11/19/2022]
Abstract
The midsagittal corpus callosum (CC) cross-sectional area subdivisions have been used as early and sensitive markers of human brain white matter connectivity, development, natural aging and disease. Despite the simplicity and conspicuity of the appearance of the CC on anatomical magnetic resonance imaging (MRI), the published quantitative MRI literature on its regional sex and age trajectories are contradictory. The availability of noninvasive quantitative methods to assess the CC regions across the human lifespan would help clarify its contribution to behavior and cognition. In this report, we extended the utility of a recently described semi-automated diffusion tensor imaging (DTI) tissue segmentation method to utilize the high orientation contrast of the CC on DTI. Using optimized DTI methods on a cohort of 121 right-handed children and adults aged 6-68 years, we examined the CC areas and corresponding DTI metrics of the different functionally specialized sectors of the CC. Both the area and fractional anisotropy metrics followed inverted U-shaped curves, while the mean and radial diffusivities followed U-curves reflecting white matter progressive and regressive myelination dynamics that continue into young adulthood.
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Affiliation(s)
- Khader M Hasan
- Department of Diagnostic and Interventional Imaging, University of Texas Medical School at Houston, 6431 Fannin Street, MSB 2.100, Houston, Texas 77030, USA.
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165
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Jea A, Vachhrajani S, Widjaja E, Nilsson D, Raybaud C, Shroff M, Rutka JT. Corpus callosotomy in children and the disconnection syndromes: a review. Childs Nerv Syst 2008; 24:685-92. [PMID: 18373102 DOI: 10.1007/s00381-008-0626-4] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2008] [Indexed: 11/24/2022]
Abstract
OBJECTS Disconnection syndromes following corpus callosotomy represent complex and variably expressed groupings of signs and symptoms affecting motor control, spatial orientation, vision, hearing, and language. Little is known, however, about the functional topography of callosal fiber pathways. In addition, most published case reports and case series of corpus callosotomy seldom report neurological deficits. We sought to categorize these deficits based on surgical anatomy. METHODS We comprehensively reviewed the literature and described, compiled, and tabulated the most common disconnection syndromes complicating corpus callosotomy. We depict the topography of the cerebral cortex and associated commissural fibers of the corpus callosum through illustrations and diffusion tensor imaging tractography. CONCLUSIONS Anatomical classification of disconnection syndromes will provide great value to neurosurgeons embarking on callosotomy, whether partial or complete. Such information will apply to procedures performed for epilepsy and to procedures where the corpus callosum is sectioned for access to lesions within the ventricular system.
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Affiliation(s)
- Andrew Jea
- Division of Neurosurgery, Department of Surgery, Hospital for Sick Children, University of Toronto Faculty of Medicine, Suite 1503, 555 University Avenue, Toronto, Ontario, Canada M5G 1X8
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166
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Weiss N, Galanaud D, Carpentier A, Naccache L, Puybasset L. Clinical review: Prognostic value of magnetic resonance imaging in acute brain injury and coma. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2008; 11:230. [PMID: 17980050 PMCID: PMC2556735 DOI: 10.1186/cc6107] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Progress in management of critically ill neurological patients has led to improved survival rates. However, severe residual neurological impairment, such as persistent coma, occurs in some survivors. This raises concerns about whether it is ethically appropriate to apply aggressive care routinely, which is also associated with burdensome long-term management costs. Adapting the management approach based on long-term neurological prognosis represents a major challenge to intensive care. Magnetic resonance imaging (MRI) can show brain lesions that are not visible by computed tomography, including early cytotoxic oedema after ischaemic stroke, diffuse axonal injury after traumatic brain injury and cortical laminar necrosis after cardiac arrest. Thus, MRI increases the accuracy of neurological diagnosis in critically ill patients. In addition, there is some evidence that MRI may have potential in terms of predicting outcome. Following a brief description of the sequences used, this review focuses on the prognostic value of MRI in patients with traumatic brain injury, anoxic/hypoxic encephalopathy and stroke. Finally, the roles played by the main anatomical structures involved in arousal and awareness are discussed and avenues for future research suggested.
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Affiliation(s)
- Nicolas Weiss
- Department of Anesthesiology and Critical Care, Pitié-Salpêtrière Teaching Hospital, Assistance Publique-Hopitaux de Paris and Pierre et Marie Curie University, Bd de l'hôpital, 75013, Paris, France
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167
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Sugiyama K, Kondo T, Higano S, Endo M, Watanabe H, Shindo K, Izumi SI. Diffusion tensor imaging fiber tractography for evaluating diffuse axonal injury. Brain Inj 2008; 21:413-9. [PMID: 17487639 DOI: 10.1080/02699050701311042] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Patients with Diffuse axonal injury (DAI) frequently exhibit cognitive disorders chronically. Radiologic recognition of DAI can help understand the clinical syndrome and to make treatment decisions. However, CT and conventional MRI are often normal or demonstrate lesions that are poorly related to the cognitive disorders. Recently, diffusion tensor imaging (DTI) fiber tractography has been shown to be useful in detecting various types of white matter damage. The aim of this study was to evaluate the feasibility of using DTI fiber tractography to detect lesions in DAI patients, and to correlate the DAI lesions with the cognitive disorders. We investigated two patients with chronic DAI. Both had impaired intelligence, as well as attention and memory disorders that restricted their activities of daily living. In both patients, DTI fiber tractography revealed interruption of the white matter fibers in the corpus collosum and the fornix, while no lesions were found on conventional MRI. The interruption of the fornix which involves the circuit of Papez potentially correlates with the memory disorder. Therefore, DTI fiber tractography may be a useful technique for the evaluation of DAI patients with cognitive disorders.
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Affiliation(s)
- Ken Sugiyama
- Department of Physical Medicine and Rehabilitation, Tohoku University Graduate School of Medicine, Sendai, Japan.
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168
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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.
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169
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Abstract
PURPOSE OF REVIEW Developments in imaging following traumatic brain injury are outlined. Numerous techniques have evolved over the past several years giving us more information about the injury and prognosis for recovery. Some of these techniques are in clinical use while others are used primarily in research but have the potential to become clinically useful. RECENT FINDINGS Computed tomography (CT) scanning is the primary imaging technique for acute brain injury, giving rapid information and being part of a general trauma work up in the emergency situation. It has supplanted plain films in the immediate management of brain injury. Following stabilization, MRI is the method of choice for evaluating the full extent of brain injury. Information on diffuse axonal injury is obtained by several MRI sequences. Diffusion tensor imaging is able to show long tract damage and relates to prognosis. There are several techniques which are best suited to research in brain injury, including single photon emission CT, PET and xenon CT. SUMMARY CT and MRI are now the imaging techniques for acute and subacute brain injury, respectively. Diffusion tensor imaging is being developed to provide more information on structural damage in brain injury. There are several research techniques available for brain injury, particularly relating to cerebral blood flow and metabolism.
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170
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Diffusion tensor imaging reliably detects experimental traumatic axonal injury and indicates approximate time of injury. J Neurosci 2007; 27:11869-76. [PMID: 17978027 DOI: 10.1523/jneurosci.3647-07.2007] [Citation(s) in RCA: 344] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Traumatic axonal injury (TAI) may contribute greatly to neurological impairments after traumatic brain injury, but it is difficult to assess with conventional imaging. We quantitatively compared diffusion tensor imaging (DTI) signal abnormalities with histological and electron microscopic characteristics of pericontusional TAI in a mouse model. Two DTI parameters, relative anisotropy and axial diffusivity, were significantly reduced 6 h to 4 d after trauma, corresponding to relatively isolated axonal injury. One to 4 weeks after trauma, relative anisotropy remained decreased, whereas axial diffusivity "pseudo-normalized" and radial diffusivity increased. These changes corresponded to demyelination, edema, and persistent axonal injury. At every time point, DTI was more sensitive to injury than conventional magnetic resonance imaging, and relative anisotropy distinguished injured from control mice with no overlap between groups. Remarkably, DTI changes strongly predicted the approximate time since trauma. These results provide an important validation of DTI for pericontusional TAI and suggest novel clinical and forensic applications.
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171
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Yuan W, Holland SK, Schmithorst VJ, Walz NC, Cecil KM, Jones BV, Karunanayaka P, Michaud L, Wade SL. Diffusion tensor MR imaging reveals persistent white matter alteration after traumatic brain injury experienced during early childhood. AJNR Am J Neuroradiol 2007; 28:1919-25. [PMID: 17905895 PMCID: PMC4295209 DOI: 10.3174/ajnr.a0698] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Diffusion tensor imaging (DTI) can noninvasively quantify white matter (WM) integrity. Although its application in adult traumatic brain injury (TBI) is common, few studies in children have been reported. The purposes of this study were to examine the alteration of fractional anisotropy (FA) in children with TBI experienced during early childhood and to quantify the association between FA and injury severity. MATERIALS AND METHODS FA was assessed in 9 children with TBI (age = 7.89 +/- 1.00 years; Glasgow Coma Scale [GCS] = 10.11 +/- 4.68) and a control group of 12 children with orthopedic injuries without central nervous system involvement (age = 7.51 +/- 0.95 years). All of the subjects were at minimum 12 months after injury. We examined group differences in a series of predetermined WM regions of interest with t test analysis. We subsequently conducted a voxel-wise comparison with Spearman partial correlation analysis. Correlations between FA and injury severity were also calculated on a voxel-wise basis. RESULTS FA values were significantly reduced in the TBI group in genu of corpus callosum (CC), posterior limb of internal capsule (PLIC), superior longitudinal fasciculus (SLF), superior fronto-occipital fasciculus (SFO), and centrum semiovale (CS). GCS scores were positively correlated with FA in several WM areas including CC, PLIC, SLF, CS, SFO, and inferior fronto-occipital fasciculus (IFO). CONCLUSION This DTI study provides evidence that WM integrity remains abnormal in children with moderate-to-severe TBI experienced during early childhood and that injury severity correlated strongly with FA.
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Affiliation(s)
- W Yuan
- Departments of Radiology, Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
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172
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Müller-Forell W, Engelhard K. Neuroimaging for the anesthesiologist. Anesthesiol Clin 2007; 25:413-39, vii-viii. [PMID: 17884702 DOI: 10.1016/j.anclin.2007.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Neuroimaging is essential in the treatment of cerebral nervous system disorders or in patients in the ICU with deterioration of their neurologic function. Leading clinical symptoms are acute neurologic deficits with different stages of hemisymptomatology, primary or progressing loss of consciousness or vigilance deficit, focal or generalized seizures, sometimes combined with an acute respiratory or circulatory insufficiency. The resulting questions can be summarized in those of intracranial space occupying hemorrhage; acute infarction; and signs for reduced cerebral blood flow, cerebrovascular vasospasm, or intracranial mass. Recent evolutions in imaging have contributed to an increase in diagnostic sensitivity and specificity along with reduced side effects. This article illustrates typical and atypical differential diagnoses, with some emphasis on traumatic brain injury.
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Affiliation(s)
- Wibke Müller-Forell
- Institute of Neuroradiology, Johannes Gutenberg-University of Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany.
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173
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Rollins NK. Clinical applications of diffusion tensor imaging and tractography in children. Pediatr Radiol 2007; 37:769-80. [PMID: 17598098 DOI: 10.1007/s00247-007-0524-z] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 04/24/2007] [Accepted: 05/02/2007] [Indexed: 11/26/2022]
Abstract
Diffusion tensor imaging (DTI) is a relatively new addition to routine MR imaging. DTI exploits the preferential movement of water protons within the brain along the axis of the axons. This anisotropic diffusion provides information about the immature brain prior to myelination, during maturation, and in normal and disease states, information that MRI cannot provide. By virtue of sensitivity to anisotropic movement of protons, DTI allows the core of larger individual white matter tracts to be visualized as discreet anatomic structures. DTI can also provide information about the microarchitecture of white matter in the form of metrics referred to as fractional anisotropy and diffusivity. The information contained within the diffusion tensor data can be used to create 3-D mathematical renderings of white matter or tractography. This article is an introduction to DTI for pediatric radiologists interested in exploring potential applications in children.
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Affiliation(s)
- Nancy K Rollins
- Children's Medical Center of Dallas, University of Texas Southwestern Medical Center, 1935 Motor St., Dallas, TX 75235, USA.
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174
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Abstract
Head injury remains an important cause of death and disability in young adults. This review will discuss the role of structural imaging using computed tomography (CT) and magnetic resonance imaging (MRI) and physiological imaging using CT perfusion, 131Xe CT, MRI and spectroscopy (MRS), single photon emission computed tomography, and positron emission tomography (PET) in the assessment, management, and prediction of outcome after head injury. CT allows rapid assessment of brain pathology which ensures patients who require urgent surgical intervention receive appropriate care. Although MRI provides greater spatial resolution, particularly within the posterior fossa and deep white matter, a complete assessment of the burden of injury requires imaging of cerebral physiology. Physiological imaging techniques can only provide 'snap shots' of physiology within the injured brain, but they can be repeated, and such data can be used to assess the impact of therapeutic interventions. Perfusion imaging based on CT techniques (xenon CT and CT perfusion) can be implemented easily in most hospital centres, and provide quantitative perfusion data in addition to structural images. PET imaging provides unparalleled insights into cerebral physiology and pathophysiology, but is not widely available and is primarily a research tool. MR technology continues to develop and is becoming generally available. Using a complex variety of sequences, MR can provide data concerning both structural and physiological derangements. Future developments with such imaging techniques should improve understanding of the pathophysiology of brain injury and provide data that should improve management and prediction of functional outcome.
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Affiliation(s)
- J P Coles
- University Department of Anaesthesia, Addenbrooke's Hospital, Box 93, Hills Road, Cambridge CB2 2QQ, UK.
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175
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Lemaire JJ, Coste J, Ouchchane L, Caire F, Nuti C, Derost P, Cristini V, Gabrillargues J, Hemm S, Durif F, Chazal J. Brain mapping in stereotactic surgery: a brief overview from the probabilistic targeting to the patient-based anatomic mapping. Neuroimage 2007; 37 Suppl 1:S109-15. [PMID: 17644002 DOI: 10.1016/j.neuroimage.2007.05.055] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2007] [Revised: 05/18/2007] [Accepted: 05/22/2007] [Indexed: 11/23/2022] Open
Abstract
In this article, we briefly review the concept of brain mapping in stereotactic surgery taking into account recent advances in stereotactic imaging. The gold standard continues to rely on probabilistic and indirect targeting, relative to a stereotactic reference, i.e., mostly the anterior (AC) and the posterior (PC) commissures. The theoretical position of a target defined on an atlas is transposed into the stereotactic space of a patient's brain; final positioning depends on electrophysiological analysis. The method is also used to analyze final electrode or lesion position for a patient or group of patients, by projection on an atlas. Limitations are precision of definition of the AC-PC line, probabilistic location and reliability of the electrophysiological guidance. Advances in MR imaging, as from 1.5-T machines, make stereotactic references no longer mandatory and allow an anatomic mapping based on an individual patient's brain. Direct targeting is enabled by high-quality images, an advanced anatomic knowledge and dedicated surgical software. Labeling associated with manual segmentation can help for the position analysis along non-conventional, interpolated planes. Analysis of final electrode or lesion position, for a patient or group of patients, could benefit from the concept of membership, the attribution of a weighted membership degree to a contact or a structure according to its level of involvement. In the future, more powerful MRI machines, diffusion tensor imaging, tractography and computational modeling will further the understanding of anatomy and deep brain stimulation effects.
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Affiliation(s)
- Jean-Jacques Lemaire
- CHU Clermont-Ferrand, Hôpital Gabriel Montpied, Service de Neurochirurgie A, Clermont-Ferrand, F-63003, France.
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176
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Yeates KO, Bigler ED, Dennis M, Gerhardt CA, Rubin KH, Stancin T, Taylor HG, Vannatta K. Social outcomes in childhood brain disorder: a heuristic integration of social neuroscience and developmental psychology. Psychol Bull 2007; 133:535-56. [PMID: 17469991 PMCID: PMC2841002 DOI: 10.1037/0033-2909.133.3.535] [Citation(s) in RCA: 316] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The authors propose a heuristic model of the social outcomes of childhood brain disorder that draws on models and methods from both the emerging field of social cognitive neuroscience and the study of social competence in developmental psychology/psychopathology. The heuristic model characterizes the relationships between social adjustment, peer interactions and relationships, social problem solving and communication, social-affective and cognitive-executive processes, and their neural substrates. The model is illustrated by research on a specific form of childhood brain disorder, traumatic brain injury. The heuristic model may promote research regarding the neural and cognitive-affective substrates of children's social development. It also may engender more precise methods of measuring impairments and disabilities in children with brain disorder and suggest ways to promote their social adaptation.
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Affiliation(s)
- Keith Owen Yeates
- Department of Pediatrics, The Ohio State University, Center for Biobehavioral Health, Columbus Children's Research Institute, Columbus, OH, USA.
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177
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Wozniak JR, Krach L, Ward E, Mueller BA, Muetzel R, Schnoebelen S, Kiragu A, Lim KO. Neurocognitive and neuroimaging correlates of pediatric traumatic brain injury: a diffusion tensor imaging (DTI) study. Arch Clin Neuropsychol 2007; 22:555-68. [PMID: 17446039 PMCID: PMC2887608 DOI: 10.1016/j.acn.2007.03.004] [Citation(s) in RCA: 209] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2007] [Revised: 03/12/2007] [Accepted: 03/14/2007] [Indexed: 12/28/2022] Open
Abstract
This study examined the sensitivity of diffusion tensor imaging (DTI) to microstructural white matter (WM) damage in mild and moderate pediatric traumatic brain injury (TBI). Fourteen children with TBI and 14 controls ages 10-18 had DTI scans and neurocognitive evaluations at 6-12 months post-injury. Groups did not differ in intelligence, but children with TBI showed slower processing speed, working memory and executive deficits, and greater behavioral dysregulation. The TBI group had lower fractional anisotropy (FA) in three WM regions: inferior frontal, superior frontal, and supracallosal. There were no group differences in corpus callosum. FA in the frontal and supracallosal regions was correlated with executive functioning. Supracallosal FA was also correlated with motor speed. Behavior ratings showed correlations with supracallosal FA. Parent-reported executive deficits were inversely correlated with FA. Results suggest that DTI measures are sensitive to long-term WM changes and associated with cognitive functioning following pediatric TBI.
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Affiliation(s)
- Jeffrey R Wozniak
- Department of Psychiatry, University of Minnesota Medical Center, 2450 Riverside Avenue, Minneapolis, MN 55454, USA.
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178
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Mac Donald CL, Dikranian K, Song SK, Bayly PV, Holtzman DM, Brody DL. Detection of traumatic axonal injury with diffusion tensor imaging in a mouse model of traumatic brain injury. Exp Neurol 2007; 205:116-31. [PMID: 17368446 PMCID: PMC1995439 DOI: 10.1016/j.expneurol.2007.01.035] [Citation(s) in RCA: 225] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2006] [Revised: 01/22/2007] [Accepted: 01/23/2007] [Indexed: 12/31/2022]
Abstract
Traumatic axonal injury (TAI) is thought to be a major contributor to cognitive dysfunction following traumatic brain injury (TBI), however TAI is difficult to diagnose or characterize non-invasively. Diffusion tensor imaging (DTI) has shown promise in detecting TAI, but direct comparison to histologically-confirmed axonal injury has not been performed. In the current study, mice were imaged with DTI, subjected to a moderate cortical controlled impact injury, and re-imaged 4-6 h and 24 h post-injury. Axonal injury was detected by amyloid beta precursor protein (APP) and neurofilament immunohistochemistry in pericontusional white matter tracts. The severity of axonal injury was quantified using stereological methods from APP stained histological sections. Two DTI parameters--axial diffusivity and relative anisotropy--were significantly reduced in the injured, pericontusional corpus callosum and external capsule, while no significant changes were seen with conventional MRI in these regions. The contusion was easily detectable on all MRI sequences. Significant correlations were found between changes in relative anisotropy and the density of APP stained axons across mice and across subregions spanning the spatial gradient of injury. The predictive value of DTI was tested using a region with DTI changes (hippocampal commissure) and a region without DTI changes (anterior commissure). Consistent with DTI predictions, there was histological detection of axonal injury in the hippocampal commissure and none in the anterior commissure. These results demonstrate that DTI is able to detect axonal injury, and support the hypothesis that DTI may be more sensitive than conventional imaging methods for this purpose.
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Affiliation(s)
- C L Mac Donald
- Department of Biomedical Engineering, Washington University, One Brookings Drive, Campus Box 1097, St. Louis, MO 63110, USA
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179
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Newsome MR, Scheibel RS, Hunter JV, Wang ZJ, Chu Z, Li X, Levin HS. Brain activation during working memory after traumatic brain injury in children. Neurocase 2007; 13:16-24. [PMID: 17454685 DOI: 10.1080/13554790601186629] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Eight children with moderate to severe traumatic brain injury (TBI) and eight matched, uninjured control children underwent fMRI during an N-back task to test effects of TBI on working memory performance and brain activation. Two patterns in the TBI group were observed. Patients whose criterion performance was reached at lower memory loads than control children demonstrated less extensive frontal and extrafrontal brain activation than controls. Patients who performed the same, highest (3-back) memory load as controls demonstrated more frontal and extrafrontal activation than controls. Our findings of performance and brain activation changes in children after TBI await longitudinal investigation.
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Affiliation(s)
- Mary R Newsome
- Cognitive Neuroscience Laboratory, Baylor College of Medicine, Houston, TX 77030, USA.
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