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Wiggins CJ, Schäfer A, Dhital B, Le Bihan D, Turner R. After over 200 years, 7 T magnetic resonance imaging reveals the foliate structure of the human corpus callosum in vivo. Br J Radiol 2017; 90:20160906. [PMID: 28368659 PMCID: PMC5605111 DOI: 10.1259/bjr.20160906] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Objective: A fine structure of the corpus callosum (CC), consisting of radial lines, is seen in historical anatomical atlases as far back as that of Vicq d'Azyr (1786). This study examines a similar pattern observed in vivo using high-resolution MR images at 7 T. Methods: 8 healthy subjects were examined with 7.0-T MRI. Anatomical images were collected with a gradient echo scan with 0.5-mm isotropic resolution, which were rated for visibility of the radial pattern. In addition, the second eigenvector of the diffusion tensor images was examined. Results: The fine radial lines are detected not only in the sagittal view but also in the axial view of the in vivo MR images. From this, it is likely that these structures are two-dimensional ribbons. Interestingly, and confirming the structural nature of these stripes, the second eigenvector of the diffusion tensor imaging data shows an extremely similar pattern of oriented foliate structure. A similar modular structure involving transient septa has been observed previously in histological sections of human fetal CC. Conclusion: The separate sets of data—the atlas of Klingler, anatomical images and second eigenvector images—all indicate a ribbon-like arrangement of the fibres in the CC. As such, they closely match the structures shown in the drawn atlases of as old as 1786. Advances in knowledge: This ribbon arrangement of fibres in the CC, previously unseen in CT or lower field MRI, can now be observed in vivo. This appears to match over two centuries of ex vivo observations.
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Affiliation(s)
| | - Andreas Schäfer
- 2 Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,3 Siemens Healthcare GmbH, Diagnostic Imaging, Magnetic Resonance, Erlangen, Germany
| | - Bibek Dhital
- 4 Department of Radiology-Medical Physics, University Medical Center, Freiburg, Germany
| | - Denis Le Bihan
- 5 NeuroSpin, Joliot Institute, CEA-Saclay Center, Gif-sur-Yvette, France
| | - Robert Turner
- 3 Siemens Healthcare GmbH, Diagnostic Imaging, Magnetic Resonance, Erlangen, Germany.,6 University of Amsterdam Faculty of Medicine (AMC-UvA), Amsterdam, Netherlands.,7 Department of Physics, University of Nottingham, Nottingham, UK
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2
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Zhong J, Chen DQ, Walker M, Waspe A, Looi T, Piorkowska K, Drake JM, Hodaie M. An In vivo Multi-Modal Structural Template for Neonatal Piglets Using High Angular Resolution and Population-Based Whole-Brain Tractography. Front Neuroanat 2016; 10:92. [PMID: 27729850 PMCID: PMC5037218 DOI: 10.3389/fnana.2016.00092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 09/14/2016] [Indexed: 11/13/2022] Open
Abstract
An increasing number of applications use the postnatal piglet model in neuroimaging studies, however, these are based primarily on T1 weighted image templates. There is a growing need for a multimodal structural brain template for a comprehensive depiction of the piglet brain, particularly given the growing applications of diffusion weighted imaging for characterizing tissue microstructures and white matter organization. In this study, we present the first multimodal piglet structural brain template which includes a T1 weighted image with tissue segmentation probability maps, diffusion weighted metric templates with multiple diffusivity maps, and population-based whole-brain fiber tracts for postnatal piglets. These maps provide information about the integrity of white matter that is not available in T1 images alone. The availability of this diffusion weighted metric template will contribute to the structural imaging analysis of the postnatal piglet brain, especially models that are designed for the study of white matter diseases. Furthermore, the population-based whole-brain fiber tracts permit researchers to visualize the white matter connections in the piglet brain across subjects, guiding the delineation of a specific white matter region for structural analysis where current diffusion data is lacking. Researchers are able to augment the tracts by merging tracts from their own data to the population-based fiber tracts and thus improve the confidence of the population-wise fiber distribution.
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Affiliation(s)
- Jidan Zhong
- Division of Brain, Imaging and Behaviour - Systems Neuroscience, Krembil Research Institute, University Health Network, Toronto ON, Canada
| | - David Q Chen
- Division of Brain, Imaging and Behaviour - Systems Neuroscience, Krembil Research Institute, University Health Network, TorontoON, Canada; Institute of Medical Science, University of Toronto, TorontoON, Canada
| | - Matthew Walker
- Division of Brain, Imaging and Behaviour - Systems Neuroscience, Krembil Research Institute, University Health Network, TorontoON, Canada; Institute of Medical Science, University of Toronto, TorontoON, Canada
| | - Adam Waspe
- Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto ON, Canada
| | - Thomas Looi
- Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto ON, Canada
| | - Karolina Piorkowska
- Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto ON, Canada
| | - James M Drake
- Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, TorontoON, Canada; Division of Neurosurgery, The Hospital for Sick Children, TorontoON, Canada
| | - Mojgan Hodaie
- Division of Brain, Imaging and Behaviour - Systems Neuroscience, Krembil Research Institute, University Health Network, TorontoON, Canada; Institute of Medical Science, University of Toronto, TorontoON, Canada; Division of Neurosurgery, Toronto Western Hospital - University of Toronto, TorontoON, Canada
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3
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Diffusion tractography and neuromotor outcome in very preterm children with white matter abnormalities. Pediatr Res 2014; 76:86-92. [PMID: 24713814 PMCID: PMC4062577 DOI: 10.1038/pr.2014.45] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 11/21/2013] [Indexed: 11/12/2022]
Abstract
BACKGROUND Moderate-to-severe white matter abnormality (WMA) in the newborn has been shown to produce persistent disruptions in cerebral connectivity but does not universally result in neurodevelopmental disability in very preterm (VPT) children. The aims of this hypothesis-driven study were to apply diffusion imaging to: (i) examine whether bilateral WMA detected in VPT children in the newborn period can predict microstructural organization at the age of 7 y and (ii) compare corticospinal tract and corpus callosum (CC) measures in VPT children at the age of 7 y with neonatal WMA with normal vs. impaired motor functioning. METHODS Diffusion parameters of the corticospinal tract and CC were compared between VPT 7-y olds with (n = 20) and without (n = 42) bilateral WMA detected in the newborn period. For those with WMA, diffusion parameters were further examined. RESULTS Microstructural organization of corticospinal tract and CC tracts at the age of 7 y were altered in VPT children with moderate-to-severe WMA detected at term equivalent age as compared with those without injury. Furthermore, diffusion parameters differed in the CC for children with WMA categorized by motor outcome (n = 8). CONCLUSION WMA on conventional magnetic resonance imaging at term equivalent age is associated with altered microstructural organization of the corticospinal tract and CC at 7 y of age.
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Goodale MA. Separate visual systems for perception and action: a framework for understanding cortical visual impairment. Dev Med Child Neurol 2013; 55 Suppl 4:9-12. [PMID: 24237272 DOI: 10.1111/dmcn.12299] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/04/2013] [Indexed: 11/29/2022]
Abstract
The visual control of skilled goal-directed movements requires transformations of incoming visual information that are quite different from those required for visual perception. These differences in the required computations have led to the emergence of dedicated visuomotor modules in the dorsal visual stream of the cerebral cortex that are quite separate from the networks in the ventral visual stream that mediate our conscious perception of the world. Although the identification and selection of goal objects and an appropriate course of action depends on the perceptual machinery of the ventral stream and associated cognitive modules in the temporal and frontal lobes, the execution of the subsequent goal-directed action is mediated by dedicated online control systems in the dorsal stream and associated motor areas. This functional distinction can provide a useful framework for interpreting the range of perceptual and visuomotor deficits observed in children with cortical visual impairment.
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Affiliation(s)
- Melvyn A Goodale
- The Brain and Mind Institute, The University of Western Ontario, London, ON, Canada
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Lee DH, Woo YK, Hong CP. Evaluation of Callosal Motor Fiber Location in the Human Brain by Diffusion Tensor Tractography Combined with Functional MRI. J Phys Ther Sci 2013. [DOI: 10.1589/jpts.25.387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Dong-Hoon Lee
- Department of Radiological Science, College of Health Science, Yonsei University: 234 Maeji, Heungup, Wonju, Gangwondo 220-710, Republic of Korea
| | - Young-Keun Woo
- Department of Physical Therapy, College of Alternative Medicine, Jeonju University
| | - Cheol-Pyo Hong
- Department of Radiological Science, College of Health Science, Yonsei University: 234 Maeji, Heungup, Wonju, Gangwondo 220-710, Republic of Korea
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Yeatman JD, Dougherty RF, Myall NJ, Wandell BA, Feldman HM. Tract profiles of white matter properties: automating fiber-tract quantification. PLoS One 2012; 7:e49790. [PMID: 23166771 PMCID: PMC3498174 DOI: 10.1371/journal.pone.0049790] [Citation(s) in RCA: 555] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 10/17/2012] [Indexed: 11/19/2022] Open
Abstract
Tractography based on diffusion weighted imaging (DWI) data is a method for identifying the major white matter fascicles (tracts) in the living human brain. The health of these tracts is an important factor underlying many cognitive and neurological disorders. In vivo, tissue properties may vary systematically along each tract for several reasons: different populations of axons enter and exit the tract, and disease can strike at local positions within the tract. Hence quantifying and understanding diffusion measures along each fiber tract (Tract Profile) may reveal new insights into white matter development, function, and disease that are not obvious from mean measures of that tract. We demonstrate several novel findings related to Tract Profiles in the brains of typically developing children and children at risk for white matter injury secondary to preterm birth. First, fractional anisotropy (FA) values vary substantially within a tract but the Tract FA Profile is consistent across subjects. Thus, Tract Profiles contain far more information than mean diffusion measures. Second, developmental changes in FA occur at specific positions within the Tract Profile, rather than along the entire tract. Third, Tract Profiles can be used to compare white matter properties of individual patients to standardized Tract Profiles of a healthy population to elucidate unique features of that patient's clinical condition. Fourth, Tract Profiles can be used to evaluate the association between white matter properties and behavioral outcomes. Specifically, in the preterm group reading ability is positively correlated with FA measured at specific locations on the left arcuate and left superior longitudinal fasciculus and the magnitude of the correlation varies significantly along the Tract Profiles. We introduce open source software for automated fiber-tract quantification (AFQ) that measures Tract Profiles of MRI parameters for 18 white matter tracts. With further validation, AFQ Tract Profiles have potential for informing clinical management and decision-making.
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Affiliation(s)
- Jason D Yeatman
- Department of Psychology, Stanford University, Stanford, California, United States of America.
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Jo HM, Cho HK, Jang SH, Yeo SS, Lee E, Kim HS, Son SM. A comparison of microstructural maturational changes of the corpus callosum in preterm and full-term children: a diffusion tensor imaging study. Neuroradiology 2012; 54:997-1005. [PMID: 22562691 DOI: 10.1007/s00234-012-1042-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 04/19/2012] [Indexed: 10/28/2022]
Abstract
INTRODUCTION Preterm children with thinning of the corpus callosum (CC) frequently achieve poor neurodevelopmental outcomes despite the absence of a definite brain lesion. Here, the authors compared the microstructural characteristics of the CC in preterm and full-term children using diffusion tensor imaging (DTI). METHODS Twenty-two preterm children with no definite focal lesion but with thinning of the CC by conventional magnetic resonance imaging and 23 age-matched full-term children were investigated by DTI. CCs were subdivided into genu, rostral body, body, isthmus, and splenium, and voxel counts (VC), fractional anisotropies (FA), and apparent diffusion coefficients (ADC) were measured in each subdivision. Eleven preterm and 11 age-matched full-term subjects underwent follow-up scanning and interval changes in these parameters for each subdivision were compared. RESULTS VC and FA were significantly lower in the preterm group than in the full-term group, particularly in the isthmus. Furthermore, incremental changes in VC and FA were significantly smaller in the preterm group. Differences in maturation between the two groups were more pronounced with age in all subdivisions except the splenium. At all ages, noticeable FA differences between the two groups were observed in the isthmus. For white matter tracts, the preterm group displayed lower FA and fiber number, higher ADC values than the term group. CONCLUSIONS The present study shows that thinning of the CC is correlated with lower FA value and that it is more pronounced in preterm children. In addition, the isthmus was found to be the most vulnerable subdivision in preterm children.
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Affiliation(s)
- Hae Min Jo
- Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, University 317-1, Daemyungdong, Namku, Taegu 705-717, Republic of Korea
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Epelman M, Daneman A, Halliday W, Whyte H, Blaser SI. Abnormal corpus callosum in neonates after hypoxic-ischemic injury. Pediatr Radiol 2012; 42:321-30. [PMID: 21935701 DOI: 10.1007/s00247-011-2238-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 07/30/2011] [Accepted: 08/05/2011] [Indexed: 11/25/2022]
Abstract
BACKGROUND Literature regarding callosal injury after hypoxic-ischemic injury (HII) is scant. OBJECTIVE To present the MRI and US findings of callosal injury after HII. MATERIALS AND METHODS MRI and US studies of 76 neonates were evaluated for HII and 53 were considered positive. RESULTS Of the 53 neonates with HII, 40 demonstrated restricted diffusion on DWI; of these, 30 revealed callosal involvement. Nine of the 13 neonates with normal DWI, whose routine MRI images were compatible with HII, were imaged after 1 week of age. Five out of ten neonates imaged during the 1st week of life who did not show callosal restriction on DWI had predominantly basal ganglia injury. Callosal US images were regarded as abnormal in 16 out of the 53 neonates with HII, 15 of which revealed concomitant restricted diffusion on DWI. CONCLUSION Callosal injuries are common after HII. DWI is effective in confirming these injuries and easily demonstrates injury if performed prior to 1 week of age. The restricted diffusion demonstrated after this time could be attributed to continued injury. US is not a sensitive modality for callosal injury detection; however, abnormally increased callosal echogenicity might be a specific marker of injury in this setting.
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Affiliation(s)
- Monica Epelman
- Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, Canada.
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Abstract
BACKGROUND Hemihydranencephaly (HHDNC) is a rare disorder with complete or almost complete unilateral absence of cerebral cortex. METHODS This study describes a 27 months-old girl presenting with developmental delay and generalized weakness more on the left side. Bilateral blindness was noted since the age of 6 months. RESULTS Her fundus examination revealed bilateral optic atrophy, dilated tortuous retinal veins with increased intra-ocular tension. She had polyuria and recurrent attacks of dehydration due to neurogenic diabetes insipidus. Her blood protein S was deficient. Her magnetic resonance imaging (MRI) demonstrated HHDNC with nearly complete absence of the right cerebral hemisphere. Her MR-Arteriography demonstrated total occlusion of right middle and anterior cerebral arteries and attenuated and beaded right posterior cerebral artery. Diffusion tensor MR imaging revealed complete absence of right cortico-spinal and optic tracts with deficient left sided tracts. CONCLUSION In contrast to the good outcome of the few reported cases of HHDNC, this case had severe global disabilities.
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Yeatman JD, Feldman HM. Neural plasticity after pre-linguistic injury to the arcuate and superior longitudinal fasciculi. Cortex 2011; 49:301-11. [PMID: 21937035 DOI: 10.1016/j.cortex.2011.08.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 04/01/2011] [Accepted: 08/04/2011] [Indexed: 11/18/2022]
Abstract
We describe the case of girl who was born prematurely and diagnosed periventricular leukomalacia, a condition characterized by severe injury to the white matter tracts primarily surrounding the ventricles. At 12 years of age, we obtained diffusion tensor imaging (DTI) data on this child as part of a research protocol. Multiple analyses of DTI data, including tractography, showed that the left and right arcuate and superior longitudinal fasciculi were missing in the child though all other major white matter tracts were present. Standardized psychometric tests at age 12 years revealed that despite early language delays, she had average scores on expressive language, sentence repetition, and reading, functions that have been hypothesized to depend on signals carried by the arcuate fasciculus. We identified intact ventral connections between the temporal and frontal lobes through the extreme capsule fiber system and uncinate fasciculus. Preserved language and reading function after serious injury to the arcuate fasciculus highlights the plasticity of the developing brain after severe white matter injury early in life.
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Affiliation(s)
- Jason D Yeatman
- Department of Psychology, Stanford University, Stanford, CA, USA.
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Kim JH, Loy DN, Wang Q, Budde MD, Schmidt RE, Trinkaus K, Song SK. Diffusion tensor imaging at 3 hours after traumatic spinal cord injury predicts long-term locomotor recovery. J Neurotrauma 2010; 27:587-98. [PMID: 20001686 DOI: 10.1089/neu.2009.1063] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Accurate diagnosis of spinal cord injury (SCI) severity must be achieved before highly aggressive experimental therapies can be tested responsibly in the early phases after trauma. These studies demonstrate for the first time that axial diffusivity (lambda||), derived from diffusion tensor imaging (DTI) within 3 h after SCI, accurately predicts long-term locomotor behavioral recovery in mice. Female C57BL/6 mice underwent sham laminectomy or graded contusive spinal cord injuries at the T9 vertebral level (5 groups, n = 8 for each group). In-vivo DTI examinations were performed immediately after SCI. Longitudinal measurements of hindlimb locomotor recovery were obtained using the Basso mouse scale (BMS). Injured and spared regions of ventrolateral white matter (VLWM) were reliably separated in the hyperacute phase by threshold segmentation. Measurements of lambda|| were compared with histology in the hyperacute phase and 14 days after injury. The spared normal VLWM determined by hyperacute lambda|| and 14-day histology correlated well (r = 0.95). A strong correlation between hindlimb locomotor function recovery and lambda||-determined spared normal VLWM was also observed. The odds of significant locomotor recovery increased by 18% with each 1% increase in normal VLWM measured in the hyperacute phase (odds ratio = 1.18, p = 0.037). The capability of measuring subclinical changes in spinal cord physiology and murine genetic advantages offer an early window into the basic mechanisms of SCI that was not previously possible. Although significant obstacles must still be overcome to derive similar data in human patients, the path to clinical translation is foreseeable and achievable.
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Affiliation(s)
- Joong H Kim
- Department of Radiology, Washington University, St. Louis, Missouri, USA
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Andrews JS, Ben-Shachar M, Yeatman JD, Flom LL, Luna B, Feldman HM. Reading performance correlates with white-matter properties in preterm and term children. Dev Med Child Neurol 2010; 52:e94-100. [PMID: 19747208 PMCID: PMC2892255 DOI: 10.1111/j.1469-8749.2009.03456.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIM We used diffusion tensor imaging to investigate the association between white-matter integrity and reading ability in a cohort of 28 children. Nineteen preterm children (14 males, five females; mean age 11 y 11 mo [SD 1 y 10 mo], mean gestational age 30.5 wks (SD 3.2), mean birthweight was 1455 g [SD 625]); and nine term children (five males, four females; mean age 12 y 8 mo [SD 2 y 5 mo], mean gestational age 39.6 wks (SD 1.2), and mean birthweight 3877 g [SD 473]). METHOD We tested whether fractional anisotropy in a left hemisphere temporoparietal region and in the corpus callosum correlates with birthweight and scores on the following three subtests of the Woodcock-Johnson III Tests of Achievement: word identification, word attack, and passage comprehension. RESULTS Preterm children had lower reading scores than a comparison group for all reading subtests (p<0.05). We found significant correlations between birthweight and fractional anisotropy in the whole corpus callosum (p=0.001), and between fractional anisotropy and reading skill in the genu (p=0.001) and body (p=0.001) of the corpus callosum. The correlation between reading skill and fractional anisotropy in a left temporoparietal region previously associated with reading disability was not significant (p=0.095). INTERPRETATION We conclude that perinatal white-matter injury of the central corpus callosum may have long-term developmental implications for reading performance.
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Affiliation(s)
| | - Michal Ben-Shachar
- Department of Psychology, Stanford University, Palo Alto, CA, USA.,English Department, Bar Ilan University, Ramat Gan, Israel
| | - Jason D Yeatman
- Department of Pediatrics, Stanford University, Palo Alto, CA, USA
| | - Lynda L Flom
- Department of Radiology, University of Pittsburgh, PA, USA
| | - Beatriz Luna
- Department of Psychiatry and Psychology, University of Pittsburgh, PA, USA
| | - Heidi M Feldman
- School of Medicine, Stanford University, Palo Alto, CA, USA.,Department of Pediatrics, Stanford University, Palo Alto, CA, USA
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Abstract
Diffusion tensor imaging (DTI) is a magnetic resonance imaging technique that allows for the visualization and characterization of the white matter tracts of the brain in vivo. DTI does not assess white matter directly. Rather, it capitalizes on the fact that diffusion is isotropic (equal in all directions) in cerebral spinal fluid and cell bodies but anisotropic (greater in one direction than the other directions) in axons that comprise white matter. It provides quantitative information about the degree and direction of water diffusion within individual units of volume within the magnetic resonance image, and by inference, about the integrity of white matter. Measures from DTI can be applied throughout the brain or to regions of interest. Fiber tract reconstruction, or tractography, creates continuous 3-dimensional tracts by sequentially piecing together estimates of fiber orientation from the direction of diffusion within individual volume units. DTI has increased our understanding of white matter structure and function. DTI shows nonlinear growth of white matter tracts from childhood to adulthood. Delayed maturation of the white matter in the frontal lobes may explain the continued growth of cognitive control into adulthood. Relative to good readers, adults and children who are poor readers have evidence of white matter differences in a specific region of the temporo-parietal lobe, implicating differences in connections among brain regions as a factor in reading disorder. Measures from DTI changed in poor readers who improved their reading skills after intense remediation. DTI documents injury to white matter tracts after prematurity. Measures indicative of white matter injury are associated with motor and cognitive impairment in children born prematurely. Further research on DTI is necessary before it can become a routine clinical procedure.
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