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Yeh CL, Levar N, Broos HC, Dechert A, Potter K, Evins AE, Gilman JM. White matter integrity differences associated with post-traumatic stress disorder are not normalized by concurrent marijuana use. Psychiatry Res Neuroimaging 2020; 295:111017. [PMID: 31760337 PMCID: PMC7730843 DOI: 10.1016/j.pscychresns.2019.111017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 11/22/2022]
Abstract
Marijuana (MJ) use and post-traumatic stress disorder (PTSD) have both been associated with abnormalities in brain white matter tracts, including the cingulum and the anterior thalamic radiations (ATR), which project from subcortical regions to frontal cortex. Studies have not assessed the integrity of these tracts in patients with comorbid PTSD and MJ use. To examine effects of PTSD and MJ use on brain structure, we performed diffusion tensor imaging scans on seventy-two trauma-exposed participants, categorized into four groups: those with PTSD who used MJ at least weekly (PTSD+MJ; n = 20), those with PTSD with no regular MJ use (PTSD; n = 19), trauma-exposed controls without PTSD who used MJ (TEC+MJ; n = 14) and trauma-exposed controls with no PTSD or MJ use (TEC; n = 19). White matter integrity was evaluated by calculating fractional anisotropy (FA). Results showed that while FA values in the right ATR and the cingulum differed across groups, there were no significant interactions between PTSD and MJ in any white matter tracts, indicating that MJ exposure neither normalizes nor worsens white matter abnormalities in those with PTSD. Further study is needed to evaluate the impact of MJ use on other neurobiological markers of PTSD.
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Affiliation(s)
- Chien-Lin Yeh
- Center for Addiction Medicine, Massachusetts General Hospital, Boston, MA, USA; Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Nina Levar
- Center for Addiction Medicine, Massachusetts General Hospital, Boston, MA, USA; Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Hannah C Broos
- Center for Addiction Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Alyson Dechert
- Center for Addiction Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Kevin Potter
- Center for Addiction Medicine, Massachusetts General Hospital, Boston, MA, USA; Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - A Eden Evins
- Center for Addiction Medicine, Massachusetts General Hospital, Boston, MA, USA; Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Jodi M Gilman
- Center for Addiction Medicine, Massachusetts General Hospital, Boston, MA, USA; Department of Psychiatry, Harvard Medical School, Boston, MA, USA.
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Middleton DM, Li JY, Chen SD, White LE, Dickson PI, Matthew Ellinwood N, Provenzale JM. Quantitative diffusion tensor imaging analysis does not distinguish pediatric canines with mucopolysaccharidosis I from control canines. Neuroradiol J 2017; 30:454-460. [PMID: 28703635 DOI: 10.1177/1971400917718844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Purpose We compared fractional anisotropy and radial diffusivity measurements between pediatric canines affected with mucopolysaccharidosis I and pediatric control canines. We hypothesized that lower fractional anisotropy and higher radial diffusivity values, consistent with dysmyelination, would be present in the mucopolysaccharidosis I cohort. Methods Six canine brains, three affected with mucopolysaccharidosis I and three unaffected, were euthanized at 7 weeks and imaged using a 7T small-animal magnetic resonance imaging system. Average fractional anisotropy and radial diffusivity values were calculated for four white-matter regions based on 100 regions of interest per region per specimen. A 95% confidence interval was calculated for each mean value. Results No difference was seen in fractional anisotropy or radial diffusivity values between mucopolysaccharidosis affected and unaffected brains in any region. In particular, the 95% confidence intervals for mucopolysaccharidosis affected and unaffected canines frequently overlapped for both fractional anisotropy and radial diffusivity measurements. In addition, in some brain regions a large range of fractional anisotropy and radial diffusivity values were seen within the same cohort. Conclusion The fractional anisotropy and radial diffusivity values of white matter did not differ between pediatric mucopolysaccharidosis affected canines and pediatric control canines. Possible explanations include: (a) a lack of white matter tissue differences between mucopolysaccharidosis affected and unaffected brains at early disease stages; (b) diffusion tensor imaging does not detect any existing differences; (c) inflammatory processes such as astrogliosis produce changes that offset the decreased fractional anisotropy values and increased radial diffusivity values that are expected in dysmyelination; and (d) our sample size was insufficient to detect differences. Further studies correlating diffusion tensor imaging findings to histology are warranted.
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Affiliation(s)
| | | | - Steven D Chen
- 2 Department of Radiology, Duke University Medical Center, USA
| | - Leonard E White
- 3 Department of Orthopedic Surgery, Duke University Medical Center, USA
| | - Patricia I Dickson
- 4 Department of Pediatrics, Los Angeles Biomedical Research Institute at Harbor - UCLA Medical Center, USA
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Middleton DM, Li JY, Chen SD, White LE, Dickson P, Ellinwood NM, Provenzale JM. Diffusion tensor imaging findings suggestive of white matter alterations in a canine model of mucopolysaccharidosis type I. Neuroradiol J 2017; 31:90-94. [PMID: 28695759 DOI: 10.1177/1971400917715792] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Purpose We investigated fractional anisotropy (FA) and radial diffusivity (RD) in a canine model of mucopolysaccharidosis (MPS). We hypothesized that canines affected with MPS would exhibit decreased FA and increased RD values when compared to unaffected canines, a trend that has been previously described in humans with white matter diseases. Methods Four unaffected canines and two canines with MPS were euthanized at 18 weeks of age. Their brains were imaged using high-resolution diffusion tensor imaging (DTI) on a 7T small-animal magnetic resonance imaging system. One hundred regions of interest (ROIs) were placed in each of four white matter regions: anterior and posterior regions of the internal capsule (AIC and PIC, respectively) and anterior and posterior regions of the centrum semiovale (ACS and PCS, respectively). For each specimen, average FA and RD values and associated 95% confidence intervals were calculated from 100 ROIs for each brain region. Results For each brain region, the FA values in MPS brains were consistently lower than in unaffected dogs, and the RD values in MPS dogs were consistently higher, supporting our hypothesis. The confidence intervals for affected and unaffected canines did not overlap in any brain region. Conclusion FA and RD values followed the predicted trend in canines affected with MPS, a trend that has been described in humans with lysosomal storage and dysmyelinating diseases. These findings suggest that the canine model parallels MPS in humans, and further indicates that quantitative DTI analysis of such animals may be suitable for future study of disease progression and therapeutic response in MPS.
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Affiliation(s)
| | | | - Steven D Chen
- 2 Department of Radiology, Duke University Medical Center, USA
| | - Leonard E White
- 3 Department of Orthopaedic Surgery, Duke University Medical Center, USA
| | - Patricia Dickson
- 4 Department of Pediatrics, Los Angeles Biomedical Research Institute at Harbor - UCLA Medical Center, USA
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Wolff N, Luehr I, Sender J, Ehrlich S, Schmidt-Samoa C, Dechent P, Roessner V. A DTI study on the corpus callosum of treatment-naïve boys with 'pure' Tourette syndrome. Psychiatry Res Neuroimaging 2016; 247:1-8. [PMID: 26747579 DOI: 10.1016/j.pscychresns.2015.12.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Revised: 11/19/2015] [Accepted: 12/17/2015] [Indexed: 10/22/2022]
Abstract
Disturbances in the corpus callosum (CC) indicating altered interhemispheric connectivity have been associated with Tourette syndrome (TS). The objective of the present study was to refine knowledge about interhemispheric connectivity in TS by analyzing four different diffusion tensor imaging (DTI) parameters in a very homogeneous group of treatment-naïve boys with pure TS in comparison to male healthy controls (HC). Fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD) and mean diffusivity (MD) of five CC-segments were assessed from DTI of 26 treatment-naïve boys with pure TS and 24 HC. We observed no group differences in both FA and RD. However, we found a significant effect for AD and a trend for MD, being both reduced in boys with TS in comparison to HC. Moreover, a negative correlation between AD and the Yale Global Tic Severity Scale total score was observed. Reduced AD of the CC in treatment-naïve boys with pure TS in comparison to HC may indicate that significant alterations in white matter microstructure of the CC contribute to tic symptomatology per se and seem not to be related to confounders such as consequences of long-term medication, tic performance or tic suppression.
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Affiliation(s)
- Nicole Wolff
- Department of Child and Adolescent Psychiatry, Faculty of Medicine Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307 Dresden, Germany.
| | - Ina Luehr
- Department of Child and Adolescent Psychiatry, Faculty of Medicine Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307 Dresden, Germany
| | - Jennifer Sender
- MR-Research in Neurology and Psychiatry, Department of Cognitive Neurology, University of Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany
| | - Stefan Ehrlich
- Department of Child and Adolescent Psychiatry, Faculty of Medicine Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307 Dresden, Germany
| | - Carsten Schmidt-Samoa
- MR-Research in Neurology and Psychiatry, Department of Cognitive Neurology, University of Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany
| | - Peter Dechent
- MR-Research in Neurology and Psychiatry, Department of Cognitive Neurology, University of Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany
| | - Veit Roessner
- Department of Child and Adolescent Psychiatry, Faculty of Medicine Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307 Dresden, Germany
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Peterson DE, Chen SD, Calabrese E, White LE, Provenzale JM. Automated segmentation of the canine corpus callosum for the measurement of diffusion tensor imaging. Neuroradiol J 2015; 29:4-12. [PMID: 26577603 DOI: 10.1177/1971400915610924] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The goal of this study was to apply image registration-based automated segmentation methods to measure diffusion tensor imaging (DTI) metrics within the canine brain. Specifically, we hypothesized that this method could measure DTI metrics within the canine brain with greater reproducibility than with hand-drawn region of interest (ROI) methods. We performed high-resolution post-mortem DTI imaging on two canine brains on a 7 T MR scanner. We designated the two brains as brain 1 and brain 2. We measured DTI metrics within the corpus callosum of brain 1 using a hand-drawn ROI method and an automated segmentation method in which ROIs from brain 2 were transformed into the space of brain 1. We repeated both methods in order to measure their reliability. Mean differences between the two sets of hand-drawn ROIs ranged from 4% to 10%. Mean differences between the hand-drawn ROIs and the automated ROIs were less than 3%. The mean differences between the first and second automated ROIs were all less than 0.25%. Our findings indicate that the image registration-based automated segmentation method was clearly the more reproducible method. These results provide the groundwork for using image registration-based automated segmentation methods to measure DTI metrics within the canine brain. Such methods will facilitate the study of white matter pathology in canine models of neurologic disease.
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Affiliation(s)
| | - Steven D Chen
- Department of Radiology, Duke University Medical Center, USA
| | | | - Leonard E White
- Department of Orthopaedic Surgery, Duke University School of Medicine, USA Duke Institute for Brain Sciences, USA
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Li K, Sun Z, Han Y, Gao L, Yuan L, Zeng D. Fractional anisotropy alterations in individuals born preterm: a diffusion tensor imaging meta-analysis. Dev Med Child Neurol 2015; 57:328-38. [PMID: 25358534 DOI: 10.1111/dmcn.12618] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/28/2014] [Indexed: 12/17/2022]
Abstract
AIM This meta-analysis explored cerebral microstructural changes in individuals born preterm using fractional anisotropy from diffusion tensor imaging. METHOD We used the activation likelihood estimate (ALE) method for the meta-analysis to locate anatomical regions with white matter abnormalities in a group of individuals born preterm and in term-born comparison participants. A statistical analysis of fractional anisotropy was conducted to quantitatively explore the extent of fractional anisotropy changes in the three subregions of the corpus callosum in the preterm group. RESULTS ALE analysis identified 11 regions of decreased fractional anisotropy and four regions of increased fractional anisotropy. Analysis of the corpus callosum revealed the largest decrease in fractional anisotropy in the splenium (standardized mean difference [SMD]=-0.75, 95% confidence interval [CI] -0.93 to -0.57), followed by the body (SMD=-0.73, 95% CI -1.13 to -0.32) and the genu (SMD=-0.65, 95% CI -0.97 to -0.33). INTERPRETATION Significant changes in fractional anisotropy in individuals born preterm reflect white matter abnormalities from childhood to young adulthood, and the mechanism of fractional anisotropy alterations in preterm infants may vary during different stages of white matter development. Furthermore, the variability of fractional anisotropy between studies can primarily be attributed to the age of the individuals at scanning and to the field strength of magnetic resonance scanners.
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Affiliation(s)
- Ke Li
- Key Laboratory for NeuroInformation of Ministry of Education, University of Electronic Science and Technology of China, Chengdu, China; School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
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Mighdoll MI, Tao R, Kleinman JE, Hyde TM. Myelin, myelin-related disorders, and psychosis. Schizophr Res 2015; 161:85-93. [PMID: 25449713 DOI: 10.1016/j.schres.2014.09.040] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 09/18/2014] [Accepted: 09/21/2014] [Indexed: 12/14/2022]
Abstract
The neuropathological basis of schizophrenia and related psychoses remains elusive despite intensive scientific investigation. Symptoms of psychosis have been reported in a number of conditions where normal myelin development is interrupted. The nature, location, and timing of white matter pathology seem to be key factors in the development of psychosis, especially during the critical adolescent period of association area myelination. Numerous lines of evidence implicate myelin and oligodendrocyte function as critical processes that could affect neuronal connectivity, which has been implicated as a central abnormality in schizophrenia. Phenocopies of schizophrenia with a known pathological basis involving demyelination or dysmyelination may offer insights into the biology of schizophrenia itself. This article reviews the pathological changes in white matter of patients with schizophrenia, as well as demyelinating diseases associated with psychosis. In an attempt to understand the potential role of dysmyelination in schizophrenia, we outline the evidence from a number of both clinically-based and post-mortem studies that provide evidence that OMR genes are genetically associated with increased risk for schizophrenia. To further understand the implication of white matter dysfunction and dysmyelination in schizophrenia, we examine diffusion tensor imaging (DTI), which has shown volumetric and microstructural white matter differences in patients with schizophrenia. While classical clinical-neuropathological correlations have established that disruption in myelination can produce a high fidelity phenocopy of psychosis similar to schizophrenia, the role of dysmyelination in schizophrenia remains controversial.
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Affiliation(s)
- Michelle I Mighdoll
- Lieber Institute for Brain Development, Johns Hopkins Medical Institutions, 855 N. Wolfe Street, Suite 300, Baltimore, MD 21205, USA.
| | - Ran Tao
- Lieber Institute for Brain Development, Johns Hopkins Medical Institutions, 855 N. Wolfe Street, Suite 300, Baltimore, MD 21205, USA.
| | - Joel E Kleinman
- Lieber Institute for Brain Development, Johns Hopkins Medical Institutions, 855 N. Wolfe Street, Suite 300, Baltimore, MD 21205, USA.
| | - Thomas M Hyde
- Lieber Institute for Brain Development, Johns Hopkins Medical Institutions, 855 N. Wolfe Street, Suite 300, Baltimore, MD 21205, USA; Department of Psychiatry & Behavioral Sciences, Johns Hopkins Medical School, Baltimore, MD 21205, USA; Department of Neurology, Johns Hopkins Medical School, Baltimore, MD 21205, USA.
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Vasung L, Fischi-Gomez E, Hüppi PS. Multimodality evaluation of the pediatric brain: DTI and its competitors. Pediatr Radiol 2013; 43:60-8. [PMID: 23288478 DOI: 10.1007/s00247-012-2515-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 08/29/2012] [Indexed: 12/18/2022]
Abstract
The development of the human brain, from the fetal period until childhood, happens in a series of intertwined neurogenetical and histogenetical events that are influenced by environment. Neuronal proliferation and migration, cell aggregation, axonal ingrowth and outgrowth, dendritic arborisation, synaptic pruning and myelinisation contribute to the 'plasticity of the developing brain'. These events taken together contribute to the establishment of adult-like neuroarchitecture required for normal brain function. With the advances in technology today, mostly due to the development of non-invasive neuroimaging tools, it is possible to analyze these structural events not only in anatomical space but also longitudinally in time. In this review we have highlighted current 'state of the art' neuroimaging tools. Development of the new MRI acquisition sequences (DTI, CHARMED and phase imaging) provides valuable insight into the changes of the microstructural environment of the cortex and white matter. Development of MRI imaging tools dedicated for analysis of the acquired images (i) TBSS and ROI fiber tractography, (ii) new tissue segmentation techniques and (iii) morphometric analysis of the cortical mantle (cortical thickness and convolutions) allows the researchers to map the longitudinal changes in the macrostructure of the developing brain that go hand-in-hand with the acquisition of cognitive skills during childhood. Finally, the latest and the newest technologies, like connectom analysis and resting state fMRI connectivity analysis, today, for the first time provide the opportunity to study the developing brain through the prism of maturation of the systems and networks beyond individual anatomical areas. Combining these methods in the future and modeling the hierarchical organization of the brain might ultimately help to understand the mechanisms underlying complex brain structure function relationships of normal development and of developmental disorders.
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Affiliation(s)
- Lana Vasung
- Division of Development and Growth, Department of Pediatrics, University of Geneva, University Hospital Geneva, Rue Willy-Donzé 6, 1211 Genève 14, Geneva, Switzerland
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Negri V, Cerpa A, López-Larrubia P, Nieto-Charques L, Cerdán S, Ballesteros P. Nanotubular Paramagnetic Probes as Contrast Agents for Magnetic Resonance Imaging Based on the Diffusion Tensor. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.200906415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Negri V, Cerpa A, López-Larrubia P, Nieto-Charques L, Cerdán S, Ballesteros P. Nanotubular Paramagnetic Probes as Contrast Agents for Magnetic Resonance Imaging Based on the Diffusion Tensor. Angew Chem Int Ed Engl 2010; 49:1813-5. [DOI: 10.1002/anie.200906415] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Gaudet LM, Flavin M, Islam O, Smith GN. Diffusion MRI brain findings in neonates exposed to chorioamnionitis: a case series. JOURNAL OF OBSTETRICS AND GYNAECOLOGY CANADA 2009; 31:497-503. [PMID: 19646314 DOI: 10.1016/s1701-2163(16)34211-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVE The primary objective of this study was to determine the feasibility of using diffusion-weighted magnetic resonance imaging (DWMRI) to assess white matter changes in high-risk neonates. Secondary objectives were to determine if exposure to chorioamnionitis (clinical or histopathologic) is associated with DWMRI findings in the neonatal brain, and to calculate the sample size required for a more definitive prospective cohort study. METHODS Seventeen women with PPROM (preterm premature rupture of the membranes) who delivered 18 infants not requiring ventilatory support were recruited to participate in this case series. When stable, infants underwent DWMRI scanning. All placentas were examined for evidence of histopathologic chorioamnionitis (HCA). RESULTS There was histopathologic evidence of chorioamnionitis in seven of the 18 placentas examined; three of these patients had clinical chorioamnionitis. Diffusion MRI revealed changes in both the diffusion-weighted imaging and the apparent diffusion coefficient in three of the seven infants confirmed to have HCA (43%), while only one of the 11 infants with normal placentas (9%) showed similar findings. Routine head ultrasound examination demonstrated abnormal cortical findings that would normally prompt further investigation in only one of these infants. CONCLUSION Exposure to HCA may be associated with abnormal DWMRI findings on imaging of the neonatal brain within 96 hours of delivery. Further study is required to delineate the association of chorioamnionitis and white matter changes with long-term neurodevelopmental sequelae.
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Affiliation(s)
- Laura M Gaudet
- Department of Obstetrics and Gynaecology, Division of Maternal-Fetal Medicine, Queen's University, Kingston ON
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Helton KJ, Paydar A, Glass J, Weirich EM, Hankins J, Li CS, Smeltzer MP, Wang WC, Ware RE, Ogg RJ. Arterial spin-labeled perfusion combined with segmentation techniques to evaluate cerebral blood flow in white and gray matter of children with sickle cell anemia. Pediatr Blood Cancer 2009; 52:85-91. [PMID: 18937311 PMCID: PMC4480678 DOI: 10.1002/pbc.21745] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Changes in cerebral perfusion are an important feature of the pathophysiology of sickle cell anemia (SCA); cerebrovascular ischemia occurs frequently and leads to neurocognitive deficits, silent infarcts, and overt stroke. Non-invasive MRI methods to measure cerebral blood flow (CBF) by arterial spin labeling (ASL) afford new opportunities to characterize disease- and therapy-induced changes in cerebral hemodynamics in patients with SCA. Recent studies have documented elevated gray matter (GM) CBF in untreated children with SCA, but no measurements of white matter (WM) CBF have been reported. PROCEDURES Pulsed ASL with automated brain image segmentation-classification techniques were used to determine the CBF in GM, WM, and abnormal white matter (ABWM) of 21 children with SCA, 18 of whom were receiving hydroxyurea therapy. RESULTS GM and WM CBF were highly associated (R(2) = 0.76, P < 0.0001) and the GM to WM CBF ratio was 1.6 (95% confidence interval: 1.43-1.83). Global GM CBF in our treated cohort was 87 +/- 24 mL/min/100 g, a value lower than previously reported in untreated patients with SCA. CBF was elevated in normal appearing WM (43 +/- 14 mL/min/100 g) but decreased in ABWM (6 +/- 12 mL/min/100 g), compared to published normal pediatric controls. Hemispheric asymmetry in CBF was noted in most patients. CONCLUSIONS These perfusion measurements suggest that hydroxyurea may normalize GM CBF in children with SCA, but altered perfusion in WM may persist. This novel combined approach for CBF quantification will facilitate prospective studies of cerebral vasculopathy in SCA, particularly regarding the effects of treatments such as hydroxyurea.
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Affiliation(s)
- Kathleen J. Helton
- Correspondence to: Kathleen J. Helton, M.D., Department of Radiological Sciences, Mail Stop 210, St. Jude Children's Research Hospital, 332 North Lauderdale Street, Memphis, TN 38105, Phone: (901) 495-2412, FAX: (901) 495-3962,
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Bosnell R, Giorgio A, Johansen-Berg H. Imaging white matter diffusion changes with development and recovery from brain injury. Dev Neurorehabil 2008; 11:174-86. [PMID: 18781502 DOI: 10.1080/17518420802289065] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE This study reviews the application of diffusion tensor imaging (DTI) to the study of developmental and pathological changes in brain white matter. The ability to measure and monitor such changes in vivo would provide important opportunities for charting disease progression and monitoring response to therapeutic intervention. This study first reviews the use of DTI in studying normal human brain development. It goes on to illustrate how DTI has been used to provide insights into recovery from damage in selected brain disorders. CONCLUSIONS It is concluded that potential clinical applications of DTI include: (i) monitoring pathological change, (ii) providing markers that predict recovery and allow for individual targeting of therapy, (iii) providing outcome measures, (iv) providing measures of potentially compensatory structural changes and (v) improving understanding of normal brain anatomy to aid in interpretation of the consequences of localized damage.
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Affiliation(s)
- Rose Bosnell
- Oxford Centre for Functional MRI of the Brain, John Radcliffe Hospital, Headington, Oxford, UK
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