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Orit A Glenn - One of the best experts on this subject based on the ideXlab platform.
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J.I. Berman
2015Co-Authors: Orit A Glenn, N A Ludeman, Agnes I Bartha, Daniel B Vigneron, A J Barkovich, Donna M. Ferriero, S W Chung, R. G. HenryAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffu-sion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P .0001), transverse diffusivity (P .0001), and mean diffusivity (P .03). With increasing severity of hemiparesis, fractional anisotropy decreased (P .0001) and transverse diffu-sivity (P .0001) and mean diffusivity (P .02) increased in the affected Pyramidal tract compare
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diffusion tensor imaging of the Pyramidal Tracts in infants with motor dysfunction
Neurology, 2008Co-Authors: N A Ludeman, Jeffrey I Berman, Agnes I Bartha, A J Barkovich, Donna M. Ferriero, Rita J Jeremy, John Kornak, Roland G Henry, Orit A GlennAbstract:Objective: To determine if diffusion tensor imaging (DTI) metrics of the Pyramidal Tracts correlate with motor outcome in infants presenting with motor dysfunction. Methods: DTI tractography of the Pyramidal Tracts was performed in 21 patients with clinical motor dysfunction who were less than 30 months of age and in 22 age-matched controls. We plotted tract-specific DTI metrics (fractional anisotropy, parallel diffusivity, transverse diffusivity, and mean diffusivity) against age for the controls and generated normative curves. For each patient, we calculated the deviation from the normative curves. Patients returned for a neurodevelopmental evaluation when they were over 36 months of age, and motor outcome measures were performed. We analyzed the association between normative deviation in DTI metrics and motor outcome measures using linear and logistic regression models. Results: Normative deviation in fractional anisotropy and transverse diffusivity were significantly correlated with all measures of motor outcome. Lower fractional anisotropy and higher transverse diffusivity compared to controls were associated with worse motor outcome. Furthermore, children who were eventually diagnosed with permanent motor dysfunction had lower fractional anisotropy and higher transverse diffusivity compared with those whose motor dysfunction normalized. Conclusions: Diffusion tensor imaging metrics correlate with motor outcome in infants presenting with motor dysfunction. The identification of a quantitative imaging marker that can be applied to infants at the time of clinical presentation has implications for the evaluation of early motor dysfunction.
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diffusion tensor mr imaging tractography of the Pyramidal Tracts correlates with clinical motor function in children with congenital hemiparesis
American Journal of Neuroradiology, 2007Co-Authors: Orit A Glenn, N A Ludeman, Jeffrey I Berman, Yvonne W Wu, Agnes I Bartha, Sungwon Chung, Daniel B Vigneron, Donna M. Ferriero, Ying Lu, A J BarkovichAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffusion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P < .0001), transverse diffusivity (P < .0001), and mean diffusivity (P < .03). With increasing severity of hemiparesis, fractional anisotropy decreased (P < .0001) and transverse diffusivity (P < .0001) and mean diffusivity (P < .02) increased in the affected Pyramidal tract compared with controls. Diffusion metrics in the unaffected tract were similar to those in the control subjects. CONCLUSION: Asymmetry in fractional anisotropy, transverse diffusivity, and mean diffusivity, as well as the degree of abnormality in the actual values of the affected Pyramidal Tracts themselves, correlates with the severity of motor dysfunction in infants and children with congenital hemiparesis from different causes. This suggests that abnormalities detected by diffusion tensor MR imaging tractography in the affected Pyramidal tract are related to the functional ability of the affected Pyramidal tract, regardless of the etiology of motor dysfunction.
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diffusion tensor mr imaging tractography of the Pyramidal Tracts correlates with clinical motor function in children with congenital hemiparesis
American Journal of Neuroradiology, 2007Co-Authors: Orit A Glenn, N A Ludeman, Jeffrey I Berman, Agnes I Bartha, Daniel B Vigneron, A J Barkovich, Donna M. Ferriero, S W Chung, Roland G HenryAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffusion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P CONCLUSION: Asymmetry in fractional anisotropy, transverse diffusivity, and mean diffusivity, as well as the degree of abnormality in the actual values of the affected Pyramidal Tracts themselves, correlates with the severity of motor dysfunction in infants and children with congenital hemiparesis from different causes. This suggests that abnormalities detected by diffusion tensor MR imaging tractography in the affected Pyramidal tract are related to the functional ability of the affected Pyramidal tract, regardless of the etiology of motor dysfunction.
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dti based three dimensional tractography detects differences in the Pyramidal Tracts of infants and children with congenital hemiparesis
Journal of Magnetic Resonance Imaging, 2003Co-Authors: Orit A Glenn, Jeffrey I Berman, Daniel B Vigneron, Roland G Henry, Patrick C Chang, Steven P Miller, James A BarkovichAbstract:Purpose To test the hypothesis that there is greater asymmetry in diffusion properties between right and left Pyramidal Tracts in patients with congenital hemiparesis than in patients with normal motor function. Materials and Methods Four congenitally hemiparetic patients and four age-matched controls underwent magnetic resonance diffusion tensor imaging (DTI)-based three-dimensional tractography of the Pyramidal Tracts. Relative anisotropy, individual eigenvalues, and directionally averaged apparent diffusion coefficient were measured and degree of asymmetry was calculated. Results Compared with age-matched controls, congenitally hemiparetic patients had greater asymmetry in all measured diffusion properties. The asymmetry was characterized primarily by lower anisotropy, lower parallel diffusion, higher transverse diffusion, and slightly higher mean diffusivity in the Pyramidal tract contralateral to the hemiparesis (i.e., affected Pyramidal tract) compared with the unaffected Pyramidal tract. Conclusions There appears to be greater diffusion asymmetry between the Pyramidal Tracts in congenitally hemiparetic patients compared to controls. These differences suggest that there are alterations in the microstructure of the Pyramidal tract that controls the motor function of the hemiparetic side. Our results suggest that DTI-based three-dimensional tractography is potentially useful in the assessment of motor dysfunction in infants and children with congenital hemiparesis. J. Magn. Reson. Imaging 2003;18:641–648. © 2003 Wiley-Liss, Inc.
Armin Thron - One of the best experts on this subject based on the ideXlab platform.
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intraoperative three dimensional visualization of the Pyramidal tract in a neuronavigation system ptv reliably predicts true position of principal motor pathways
Surgical Neurology, 2003Co-Authors: Volker A Coenen, F J Hans, Heidi Kränzlein, Jürgen Weidemann, Joachim-michael Gilsbach, Timo Krings, Hubertus Axer, Armin Thron, Veit RohdeAbstract:Abstract Background This prospective study employs anisotropic diffusion-weighted (ADW) magnetic resonance imaging for the integration of individual spatial information concerning the principal motor pathways into the operating room during microneurosurgery in the central region. We hypothesize that the three-dimensional (3-D) visualization of the Pyramidal tract position (PTV) in a neuronavigation system based on ADW provides valid information concerning the position and extension of the principal motor pathways. Methods A total of 13 consecutive patients with lesions adjacent to the Pyramidal Tracts and the central region underwent microneurosurgery with the help of Pyramidal tract visualization (PTV). An ADW sequence obtained preoperatively was fused to an anatomic navigation sequence. The 3-D reconstructions of the precentral gyrus (PG), the Pyramidal tract, and the tumor were available in a customized neuronavigation system during surgery. Intraoperatively the PG was identified on the basis of the aforementioned data. Electric motorcortex stimulation (CS) was used to directly verify the PG location and indirectly the fiber tract position. Results In 11 cases (92%) the prediction of the principal motor pathways' position was correct. In one case of a meningioma, according to PTV, the tumor was falsely localized postcentrally. In the case of a precentral cavernoma, no motor response could be elicited by cortical stimulation. Conclusion Intraoperative PTV on the basis of ADW provides the neurosurgeon with reliable information concerning the position of the principal motor pathways during intracranial procedures as proved with intraoperative electrophysiological testing. The technique has the potential to reduce operative morbidity. PTV is straightforward and can be adapted to other customized neuronavigation devices.
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intraoperative three dimensional visualization of the Pyramidal tract in a neuronavigation system ptv reliably predicts true position of principal motor pathways
Surgical Neurology, 2003Co-Authors: Volker A Coenen, F J Hans, Heidi Kränzlein, Jürgen Weidemann, Joachim-michael Gilsbach, Timo Krings, Hubertus Axer, Armin Thron, Veit RohdeAbstract:Abstract Background This prospective study employs anisotropic diffusion-weighted (ADW) magnetic resonance imaging for the integration of individual spatial information concerning the principal motor pathways into the operating room during microneurosurgery in the central region. We hypothesize that the three-dimensional (3-D) visualization of the Pyramidal tract position (PTV) in a neuronavigation system based on ADW provides valid information concerning the position and extension of the principal motor pathways. Methods A total of 13 consecutive patients with lesions adjacent to the Pyramidal Tracts and the central region underwent microneurosurgery with the help of Pyramidal tract visualization (PTV). An ADW sequence obtained preoperatively was fused to an anatomic navigation sequence. The 3-D reconstructions of the precentral gyrus (PG), the Pyramidal tract, and the tumor were available in a customized neuronavigation system during surgery. Intraoperatively the PG was identified on the basis of the aforementioned data. Electric motorcortex stimulation (CS) was used to directly verify the PG location and indirectly the fiber tract position. Results In 11 cases (92%) the prediction of the principal motor pathways' position was correct. In one case of a meningioma, according to PTV, the tumor was falsely localized postcentrally. In the case of a precentral cavernoma, no motor response could be elicited by cortical stimulation. Conclusion Intraoperative PTV on the basis of ADW provides the neurosurgeon with reliable information concerning the position of the principal motor pathways during intracranial procedures as proved with intraoperative electrophysiological testing. The technique has the potential to reduce operative morbidity. PTV is straightforward and can be adapted to other customized neuronavigation devices.
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three dimensional visualization of motor cortex and Pyramidal Tracts employing functional and diffusion weighted mri methods applications and limitations
Klinische Neuroradiologie, 2001Co-Authors: Timo Krings, Volker A Coenen, L. Mayfrank, Heidi Kränzlein, W Mollerhartmann, Jürgen Weidemann, Joachim-michael Gilsbach, Hubertus Axer, Armin ThronAbstract:Background: Functional MRI (fMRI) combines anatomic with functional information and has, therefore, been widely used for preoperative planning of patients with mass lesions affecting functionally important brain regions. However, the course of functionally important fiber Tracts is not visualized. We therefore propose to combine fMRI with diffusion weighted MRI (DWI) that allows visualization of large fiber Tracts and to implement these data in a neuronavigation system. Methods: DWI was successfully performed at a field strength of 1.5 T, employing a spin-echo sequence with gradient sensitivity in six non-colinear directions to visualize the course of the Pyramidal Tracts and combined with echo-planar T2*fMRI during a hand motor task in 15 patients and 30 healthy controls. Results: Fusion of both data sets allowed visualization of the displacement of both primary sensorimotor area (M1) and corresponding large descending fiber Tracts in patients. Intraoperatively, these data were present in a neuronavigation environment. Conclusion: The combination of fMRI with DWI allows for assessment of functionally important cortical areas and additional visualization of large fiber Tracts. Information about orientation of fiber Tracts in normal appearing white matter in patients with tumors within the cortical motor system cannot be obtained by other functional or conventional imaging methods and is as vital for reducing operative morbidity as the information about functional cortex. This technique might, therefore, have the prospect of guiding neurosurgical interventions, especially when being linked to a neuronavigation system.
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in vivo 3d visualization of normal Pyramidal Tracts in human subjects using diffusion weighted magnetic resonance imaging and a neuronavigation system
Neuroscience Letters, 2001Co-Authors: Timo Krings, Diedrich Graf V. Keyserlingk, Volker A Coenen, Michael Holler, Marcus H T Reinges, Joachim-michael Gilsbach, Hubertus Axer, Armin ThronAbstract:We describe the potential of anisotropic diffusion weighted imaging to visualize the course of large cerebral fiber Tracts. Five healthy volunteers were investigated at a field strength of 1.5 Tesla, employing a spin-echo diffusion weighted sequence with gradient sensitivity in six non-collinear directions to visualize the course of the Pyramidal Tracts. The Pyramidal Tracts were segmented and reconstructed for three-dimensional visualization. Reconstruction results together with a fusioned high resolution 3D T1 weighted image data set were available in a customized neuronavigation system. Origination in the primary motor cortex, convergence in the centrum semiovale, the posterior limb of the internal capsule, the cerebral peduncles, the splitting at the level of the pons, and the Pyramidal decussation were identified in all subjects. Fiber tract maps might have the prospect of guiding neurosurgical interventions, especially when being linked to a neuronavigation system. Other potential applications include the demonstration of the anatomical substrate of functional connectivity in the human brain.
Roland G Henry - One of the best experts on this subject based on the ideXlab platform.
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diffusion tensor imaging of the Pyramidal Tracts in infants with motor dysfunction
Neurology, 2008Co-Authors: N A Ludeman, Jeffrey I Berman, Agnes I Bartha, A J Barkovich, Donna M. Ferriero, Rita J Jeremy, John Kornak, Roland G Henry, Orit A GlennAbstract:Objective: To determine if diffusion tensor imaging (DTI) metrics of the Pyramidal Tracts correlate with motor outcome in infants presenting with motor dysfunction. Methods: DTI tractography of the Pyramidal Tracts was performed in 21 patients with clinical motor dysfunction who were less than 30 months of age and in 22 age-matched controls. We plotted tract-specific DTI metrics (fractional anisotropy, parallel diffusivity, transverse diffusivity, and mean diffusivity) against age for the controls and generated normative curves. For each patient, we calculated the deviation from the normative curves. Patients returned for a neurodevelopmental evaluation when they were over 36 months of age, and motor outcome measures were performed. We analyzed the association between normative deviation in DTI metrics and motor outcome measures using linear and logistic regression models. Results: Normative deviation in fractional anisotropy and transverse diffusivity were significantly correlated with all measures of motor outcome. Lower fractional anisotropy and higher transverse diffusivity compared to controls were associated with worse motor outcome. Furthermore, children who were eventually diagnosed with permanent motor dysfunction had lower fractional anisotropy and higher transverse diffusivity compared with those whose motor dysfunction normalized. Conclusions: Diffusion tensor imaging metrics correlate with motor outcome in infants presenting with motor dysfunction. The identification of a quantitative imaging marker that can be applied to infants at the time of clinical presentation has implications for the evaluation of early motor dysfunction.
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diffusion tensor mr imaging tractography of the Pyramidal Tracts correlates with clinical motor function in children with congenital hemiparesis
American Journal of Neuroradiology, 2007Co-Authors: Orit A Glenn, N A Ludeman, Jeffrey I Berman, Agnes I Bartha, Daniel B Vigneron, A J Barkovich, Donna M. Ferriero, S W Chung, Roland G HenryAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffusion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P CONCLUSION: Asymmetry in fractional anisotropy, transverse diffusivity, and mean diffusivity, as well as the degree of abnormality in the actual values of the affected Pyramidal Tracts themselves, correlates with the severity of motor dysfunction in infants and children with congenital hemiparesis from different causes. This suggests that abnormalities detected by diffusion tensor MR imaging tractography in the affected Pyramidal tract are related to the functional ability of the affected Pyramidal tract, regardless of the etiology of motor dysfunction.
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Pyramidal tract maturation after brain injury in newborns with heart disease
Annals of Neurology, 2006Co-Authors: Jeffrey I Berman, Daniel B Vigneron, Roland G Henry, Pratik Mukherjee, Savannah C Partridge, Natalie N Charlton, Patrick S Mcquillen, Tom R Karl, James A BarkovichAbstract:Objective Our objective was to quantify white matter tract development in term newborns with congenital heart disease, a population at high risk for perioperative brain injury, using magnetic resonance imaging diffusion tensor tractography (DTT). Methods Twenty-five newborns with congenital heart disease were imaged before and after surgery, with a median of 2 weeks between serial magnetic resonance imaging examinations. DTT was performed to segment bilateral Pyramidal Tracts using semiautomated fiber tracking software, and manual region of interest measurements were taken for comparison. Results Significant maturational rates of increasing fractional anisotropy (median, 4.4% per week) and decreasing mean diffusivity (Dav) (median, −2.0% per week) in the Pyramidal tract were measured in infants without brain injury. Fractional anisotropy maturation rates were highest in newborns with normal scans, intermediate (median, 2.4% per week) in those with postoperative injury, and lowest (median, 0.9% per week) in those with preoperative injury, indicating a significant trend across brain injury groups (p = 0.015). Dav maturation rates did not differ across injury groups (p = 0.15). Manual region of interest measures showed greater variability in serial measurements, and no significant differences were identified between injury groups, suggesting that DTT may provide more sensitive measures. Interpretation DTT is feasible in term newborns and may help to characterize abnormal white matter tract development following acquired brain injury. Ann Neurol 2006
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dti based three dimensional tractography detects differences in the Pyramidal Tracts of infants and children with congenital hemiparesis
Journal of Magnetic Resonance Imaging, 2003Co-Authors: Orit A Glenn, Jeffrey I Berman, Daniel B Vigneron, Roland G Henry, Patrick C Chang, Steven P Miller, James A BarkovichAbstract:Purpose To test the hypothesis that there is greater asymmetry in diffusion properties between right and left Pyramidal Tracts in patients with congenital hemiparesis than in patients with normal motor function. Materials and Methods Four congenitally hemiparetic patients and four age-matched controls underwent magnetic resonance diffusion tensor imaging (DTI)-based three-dimensional tractography of the Pyramidal Tracts. Relative anisotropy, individual eigenvalues, and directionally averaged apparent diffusion coefficient were measured and degree of asymmetry was calculated. Results Compared with age-matched controls, congenitally hemiparetic patients had greater asymmetry in all measured diffusion properties. The asymmetry was characterized primarily by lower anisotropy, lower parallel diffusion, higher transverse diffusion, and slightly higher mean diffusivity in the Pyramidal tract contralateral to the hemiparesis (i.e., affected Pyramidal tract) compared with the unaffected Pyramidal tract. Conclusions There appears to be greater diffusion asymmetry between the Pyramidal Tracts in congenitally hemiparetic patients compared to controls. These differences suggest that there are alterations in the microstructure of the Pyramidal tract that controls the motor function of the hemiparetic side. Our results suggest that DTI-based three-dimensional tractography is potentially useful in the assessment of motor dysfunction in infants and children with congenital hemiparesis. J. Magn. Reson. Imaging 2003;18:641–648. © 2003 Wiley-Liss, Inc.
Jeffrey I Berman - One of the best experts on this subject based on the ideXlab platform.
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diffusion tensor imaging of the Pyramidal Tracts in infants with motor dysfunction
Neurology, 2008Co-Authors: N A Ludeman, Jeffrey I Berman, Agnes I Bartha, A J Barkovich, Donna M. Ferriero, Rita J Jeremy, John Kornak, Roland G Henry, Orit A GlennAbstract:Objective: To determine if diffusion tensor imaging (DTI) metrics of the Pyramidal Tracts correlate with motor outcome in infants presenting with motor dysfunction. Methods: DTI tractography of the Pyramidal Tracts was performed in 21 patients with clinical motor dysfunction who were less than 30 months of age and in 22 age-matched controls. We plotted tract-specific DTI metrics (fractional anisotropy, parallel diffusivity, transverse diffusivity, and mean diffusivity) against age for the controls and generated normative curves. For each patient, we calculated the deviation from the normative curves. Patients returned for a neurodevelopmental evaluation when they were over 36 months of age, and motor outcome measures were performed. We analyzed the association between normative deviation in DTI metrics and motor outcome measures using linear and logistic regression models. Results: Normative deviation in fractional anisotropy and transverse diffusivity were significantly correlated with all measures of motor outcome. Lower fractional anisotropy and higher transverse diffusivity compared to controls were associated with worse motor outcome. Furthermore, children who were eventually diagnosed with permanent motor dysfunction had lower fractional anisotropy and higher transverse diffusivity compared with those whose motor dysfunction normalized. Conclusions: Diffusion tensor imaging metrics correlate with motor outcome in infants presenting with motor dysfunction. The identification of a quantitative imaging marker that can be applied to infants at the time of clinical presentation has implications for the evaluation of early motor dysfunction.
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diffusion tensor mr imaging tractography of the Pyramidal Tracts correlates with clinical motor function in children with congenital hemiparesis
American Journal of Neuroradiology, 2007Co-Authors: Orit A Glenn, N A Ludeman, Jeffrey I Berman, Yvonne W Wu, Agnes I Bartha, Sungwon Chung, Daniel B Vigneron, Donna M. Ferriero, Ying Lu, A J BarkovichAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffusion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P < .0001), transverse diffusivity (P < .0001), and mean diffusivity (P < .03). With increasing severity of hemiparesis, fractional anisotropy decreased (P < .0001) and transverse diffusivity (P < .0001) and mean diffusivity (P < .02) increased in the affected Pyramidal tract compared with controls. Diffusion metrics in the unaffected tract were similar to those in the control subjects. CONCLUSION: Asymmetry in fractional anisotropy, transverse diffusivity, and mean diffusivity, as well as the degree of abnormality in the actual values of the affected Pyramidal Tracts themselves, correlates with the severity of motor dysfunction in infants and children with congenital hemiparesis from different causes. This suggests that abnormalities detected by diffusion tensor MR imaging tractography in the affected Pyramidal tract are related to the functional ability of the affected Pyramidal tract, regardless of the etiology of motor dysfunction.
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diffusion tensor mr imaging tractography of the Pyramidal Tracts correlates with clinical motor function in children with congenital hemiparesis
American Journal of Neuroradiology, 2007Co-Authors: Orit A Glenn, N A Ludeman, Jeffrey I Berman, Agnes I Bartha, Daniel B Vigneron, A J Barkovich, Donna M. Ferriero, S W Chung, Roland G HenryAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffusion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P CONCLUSION: Asymmetry in fractional anisotropy, transverse diffusivity, and mean diffusivity, as well as the degree of abnormality in the actual values of the affected Pyramidal Tracts themselves, correlates with the severity of motor dysfunction in infants and children with congenital hemiparesis from different causes. This suggests that abnormalities detected by diffusion tensor MR imaging tractography in the affected Pyramidal tract are related to the functional ability of the affected Pyramidal tract, regardless of the etiology of motor dysfunction.
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Pyramidal tract maturation after brain injury in newborns with heart disease
Annals of Neurology, 2006Co-Authors: Jeffrey I Berman, Daniel B Vigneron, Roland G Henry, Pratik Mukherjee, Savannah C Partridge, Natalie N Charlton, Patrick S Mcquillen, Tom R Karl, James A BarkovichAbstract:Objective Our objective was to quantify white matter tract development in term newborns with congenital heart disease, a population at high risk for perioperative brain injury, using magnetic resonance imaging diffusion tensor tractography (DTT). Methods Twenty-five newborns with congenital heart disease were imaged before and after surgery, with a median of 2 weeks between serial magnetic resonance imaging examinations. DTT was performed to segment bilateral Pyramidal Tracts using semiautomated fiber tracking software, and manual region of interest measurements were taken for comparison. Results Significant maturational rates of increasing fractional anisotropy (median, 4.4% per week) and decreasing mean diffusivity (Dav) (median, −2.0% per week) in the Pyramidal tract were measured in infants without brain injury. Fractional anisotropy maturation rates were highest in newborns with normal scans, intermediate (median, 2.4% per week) in those with postoperative injury, and lowest (median, 0.9% per week) in those with preoperative injury, indicating a significant trend across brain injury groups (p = 0.015). Dav maturation rates did not differ across injury groups (p = 0.15). Manual region of interest measures showed greater variability in serial measurements, and no significant differences were identified between injury groups, suggesting that DTT may provide more sensitive measures. Interpretation DTT is feasible in term newborns and may help to characterize abnormal white matter tract development following acquired brain injury. Ann Neurol 2006
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dti based three dimensional tractography detects differences in the Pyramidal Tracts of infants and children with congenital hemiparesis
Journal of Magnetic Resonance Imaging, 2003Co-Authors: Orit A Glenn, Jeffrey I Berman, Daniel B Vigneron, Roland G Henry, Patrick C Chang, Steven P Miller, James A BarkovichAbstract:Purpose To test the hypothesis that there is greater asymmetry in diffusion properties between right and left Pyramidal Tracts in patients with congenital hemiparesis than in patients with normal motor function. Materials and Methods Four congenitally hemiparetic patients and four age-matched controls underwent magnetic resonance diffusion tensor imaging (DTI)-based three-dimensional tractography of the Pyramidal Tracts. Relative anisotropy, individual eigenvalues, and directionally averaged apparent diffusion coefficient were measured and degree of asymmetry was calculated. Results Compared with age-matched controls, congenitally hemiparetic patients had greater asymmetry in all measured diffusion properties. The asymmetry was characterized primarily by lower anisotropy, lower parallel diffusion, higher transverse diffusion, and slightly higher mean diffusivity in the Pyramidal tract contralateral to the hemiparesis (i.e., affected Pyramidal tract) compared with the unaffected Pyramidal tract. Conclusions There appears to be greater diffusion asymmetry between the Pyramidal Tracts in congenitally hemiparetic patients compared to controls. These differences suggest that there are alterations in the microstructure of the Pyramidal tract that controls the motor function of the hemiparetic side. Our results suggest that DTI-based three-dimensional tractography is potentially useful in the assessment of motor dysfunction in infants and children with congenital hemiparesis. J. Magn. Reson. Imaging 2003;18:641–648. © 2003 Wiley-Liss, Inc.
A J Barkovich - One of the best experts on this subject based on the ideXlab platform.
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J.I. Berman
2015Co-Authors: Orit A Glenn, N A Ludeman, Agnes I Bartha, Daniel B Vigneron, A J Barkovich, Donna M. Ferriero, S W Chung, R. G. HenryAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffu-sion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P .0001), transverse diffusivity (P .0001), and mean diffusivity (P .03). With increasing severity of hemiparesis, fractional anisotropy decreased (P .0001) and transverse diffu-sivity (P .0001) and mean diffusivity (P .02) increased in the affected Pyramidal tract compare
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diffusion tensor imaging of the Pyramidal Tracts in infants with motor dysfunction
Neurology, 2008Co-Authors: N A Ludeman, Jeffrey I Berman, Agnes I Bartha, A J Barkovich, Donna M. Ferriero, Rita J Jeremy, John Kornak, Roland G Henry, Orit A GlennAbstract:Objective: To determine if diffusion tensor imaging (DTI) metrics of the Pyramidal Tracts correlate with motor outcome in infants presenting with motor dysfunction. Methods: DTI tractography of the Pyramidal Tracts was performed in 21 patients with clinical motor dysfunction who were less than 30 months of age and in 22 age-matched controls. We plotted tract-specific DTI metrics (fractional anisotropy, parallel diffusivity, transverse diffusivity, and mean diffusivity) against age for the controls and generated normative curves. For each patient, we calculated the deviation from the normative curves. Patients returned for a neurodevelopmental evaluation when they were over 36 months of age, and motor outcome measures were performed. We analyzed the association between normative deviation in DTI metrics and motor outcome measures using linear and logistic regression models. Results: Normative deviation in fractional anisotropy and transverse diffusivity were significantly correlated with all measures of motor outcome. Lower fractional anisotropy and higher transverse diffusivity compared to controls were associated with worse motor outcome. Furthermore, children who were eventually diagnosed with permanent motor dysfunction had lower fractional anisotropy and higher transverse diffusivity compared with those whose motor dysfunction normalized. Conclusions: Diffusion tensor imaging metrics correlate with motor outcome in infants presenting with motor dysfunction. The identification of a quantitative imaging marker that can be applied to infants at the time of clinical presentation has implications for the evaluation of early motor dysfunction.
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diffusion tensor mr imaging tractography of the Pyramidal Tracts correlates with clinical motor function in children with congenital hemiparesis
American Journal of Neuroradiology, 2007Co-Authors: Orit A Glenn, N A Ludeman, Jeffrey I Berman, Yvonne W Wu, Agnes I Bartha, Sungwon Chung, Daniel B Vigneron, Donna M. Ferriero, Ying Lu, A J BarkovichAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffusion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P < .0001), transverse diffusivity (P < .0001), and mean diffusivity (P < .03). With increasing severity of hemiparesis, fractional anisotropy decreased (P < .0001) and transverse diffusivity (P < .0001) and mean diffusivity (P < .02) increased in the affected Pyramidal tract compared with controls. Diffusion metrics in the unaffected tract were similar to those in the control subjects. CONCLUSION: Asymmetry in fractional anisotropy, transverse diffusivity, and mean diffusivity, as well as the degree of abnormality in the actual values of the affected Pyramidal Tracts themselves, correlates with the severity of motor dysfunction in infants and children with congenital hemiparesis from different causes. This suggests that abnormalities detected by diffusion tensor MR imaging tractography in the affected Pyramidal tract are related to the functional ability of the affected Pyramidal tract, regardless of the etiology of motor dysfunction.
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diffusion tensor mr imaging tractography of the Pyramidal Tracts correlates with clinical motor function in children with congenital hemiparesis
American Journal of Neuroradiology, 2007Co-Authors: Orit A Glenn, N A Ludeman, Jeffrey I Berman, Agnes I Bartha, Daniel B Vigneron, A J Barkovich, Donna M. Ferriero, S W Chung, Roland G HenryAbstract:BACKGROUND AND PURPOSE: Children with congenital hemiparesis have greater asymmetry in diffusion parameters of the Pyramidal Tracts compared with control subjects. We hypothesized that the asymmetry correlates with the severity of hemiparesis and that diffusion metrics would be abnormal in the affected Tracts and normal in the unaffected Tracts. MATERIALS AND METHODS: Fifteen patients with congenital hemiparesis and 17 age-matched control subjects were studied with diffusion tensor MR imaging tractography. Hemipareses were scored as mild, moderate, or severe. We measured tract-specific diffusion parameters (fractional anisotropy, mean, and directional diffusion coefficients) of the Pyramidal Tracts. We compared tract-specific parameters and asymmetry between the right and left Tracts of the differing severity groups and control subjects. RESULTS: We observed many different causes of congenital hemiparesis including venous infarction, arterial infarction, and polymicrogyria. Clinical severity of hemiparesis correlated with asymmetry in fractional anisotropy (P CONCLUSION: Asymmetry in fractional anisotropy, transverse diffusivity, and mean diffusivity, as well as the degree of abnormality in the actual values of the affected Pyramidal Tracts themselves, correlates with the severity of motor dysfunction in infants and children with congenital hemiparesis from different causes. This suggests that abnormalities detected by diffusion tensor MR imaging tractography in the affected Pyramidal tract are related to the functional ability of the affected Pyramidal tract, regardless of the etiology of motor dysfunction.
