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Paul D. Chumas, James M. Drake, Marc R. Del Bigio, Marcia Da Silva, and Ursula I. Tuor

bilateral readings across six different slides was measured for each anatomical region of interest. Histological Assessment Sections used for autoradiography or additional adjacent sections were stained with Luxol fast blue/hematoxylin and eosin, allowing a direct correlation of histological findings and local CMR glu data. With the internal capsule of the control animals used as a reference for full myelination, the degree of myelination in the periventricular white matter was compared with that in the superior gyri of the posterior frontal lobe and graded on a

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Joshua D. Burks, Andrew K. Conner, Phillip A. Bonney, Chad A. Glenn, Cordell M. Baker, Lillian B. Boettcher, Robert G. Briggs, Daniel L. O’Donoghue, Dee H. Wu, and Michael E. Sughrue

% formalin for at least 3 months after removal from the cranium. Up until the time of dissection, the pia-arachnoid membrane was left attached. After fixation with formalin, specimens were rinsed with water for 2 days and then frozen at −10°C for 8 hours, causing white matter disruption. After thawing, dissection of the “freeze-fractured” specimen began with removal of the meninges and identification of cortical anatomy, including gyri and sulci. Relevant cortical areas were identified first. Starting superficially, they were then peeled back to reveal white matter areas

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Francesco Vergani, Christopher M. Morris, Patrick Mitchell, and Hugues Duffau

I n recent years, there has been a growing interest in the study of white matter anatomy. The development of diffusion tensor imaging for in vivo tractography 5 , 15 , 18 and the renewed interest in postmortem dissections, usually performed by neurosurgeons, 14 , 22 , 29 have both contributed to this evolving branch of neuroanatomy. Hodotopy, the study of white matter connectivity, is of great importance, not only for a better understanding of brain functioning but also to tailor the surgical approach to the individual functional anatomy of each patient

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Hiroshi Ozawa, Takeo Matsumoto, Toshiro Ohashi, Masaaki Sato, and Shoichi Kokubun

T he gray matter of the spinal cord mainly consists of nerve cells, whereas the white matter consists of dendrites and axons. The gray matter has been thought to be softer than the white matter, although no definite evidence to this effect has been published. In 1954, Schneider, et al., 9 stated that because hemorrhage spreads in the central part of the spinal cord through several segments causing compression of the white matter, the gray matter has a relatively looser texture and less supportive strength. In 1997, Levine, 6 operating under the assumption

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Shanta E. Kapadia

extravasation occurs into the white matter, presumably by bulk flow. Further studies 18–20 have shown that over a period of time the edema in the white matter spreads to segments proximal and distal to the site of injury. Ultrastructural changes in the microvasculature of the gray matter at the site of spinal cord trauma have been described in animals injected with horseradish peroxidase after induction of trauma. 2, 3, 7–9 These changes consist of perivascular edema accompanied by increased pinocytotic activity 2, 3, 8, 9 and endothelial cell separation. 7 However, no

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Iska Moxon-Emre, Eric Bouffet, Michael D. Taylor, Normand Laperriere, Michael B. Sharpe, Suzanne Laughlin, Ute Bartels, Nadia Scantlebury, Nicole Law, David Malkin, Jovanka Skocic, Logan Richard, and Donald J. Mabbott

A critical issue in cancer therapy is characterizing the trade-off between the intensity of treatment and its long-term effects. This understanding is integral to providing care that maximizes cure rates while minimizing negative sequelae. Children with brain tumors are a particularly informative population in which to study this interplay, and they stand to benefit from treatment adjustment. In 2 medulloblastoma patient cohorts, we evaluated the relations between white matter architecture and 1) radiation treatment intensity (i.e., protocols that deliver

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Christopher M. Bonfield, Lesley M. Foley, Shinjini Kundu, Wendy Fellows-Mayle, T. Kevin Hitchens, Gustavo K. Rohde, Ramesh Grandhi, and Mark P. Mooney

unrestricted brain growth. In addition to the cosmetic ramifications attributable to premature suture fusion, aberrations in neurophysiological parameters are seen, which may result in secondary brain injury. Along with increased ICP, 13 , 14 , 18 , 22 , 28 abnormal cerebral blood flow 10 , 11 , 32 contributes to potential white matter injury in craniosynostosis. Such damage manifests as structural and physiological impairments in cortical connectivity. Conventional MRI is able to detect the structural changes noninvasively, but only in a qualitative fashion and only

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Hakseung Kim, Young-Tak Kim, Eun-Suk Song, Byung C. Yoon, Young Hun Choi, Keewon Kim, and Dong-Joo Kim

, particularly when the patient is intubated. The application of neuroimaging techniques, particularly CT, during the acute phase of an injury can compensate for this limitation, and these techniques are widely used to define the cause and extent of neurological injury. 38 Nearly all complications after TBI provoke secondary ischemia, 16 and the extent of the secondary ischemic-edematous insult is often assessed via CT during the acute phase of TBI. The extent of cerebral ischemia often manifests as the loss of gray matter (GM) and white matter (WM) differentiation on brain

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Takeshi Sasaki, Ofer Pasternak, Michael Mayinger, Marc Muehlmann, Peter Savadjiev, Sylvain Bouix, Marek Kubicki, Eli Fredman, Brian Dahlben, Karl G. Helmer, Andrew M. Johnson, Jeffrey D. Holmes, Lorie A. Forwell, Elaine N. Skopelja, Martha E. Shenton, Paul S. Echlin, and Inga K. Koerte

, 36 In addition, conventional neuroimaging such as CT and MRI fail to detect traumatic axonal injury, the underlying mechanism of mTBI. Diffusion tensor imaging (DTI) is sensitive for detecting traumatic axonal injury and is therefore expected to improve the diagnosis of mTBI by providing objective parameters to quantify and to localize white matter alterations (see review by Shenton et al. 46 ). DTI measures the movement of water in the brain. In white matter, water molecules move more in directions parallel to the fiber tracts than perpendicular to them. This

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Ken Kazumata, Khin Khin Tha, Haruto Uchino, Tohru Shiga, Hideo Shichinohe, Masaki Ito, Naoki Nakayama, and Takeo Abumiya

impaired white matter integrity in the hemisphere exposed to hyperperfusion after carotid endarterectomy. 28 In revascularization surgery for MMD, gray matter lesions are transiently found on conventional MRI. 13 , 16 Subcortical edema has also been reported, although it is not frequently found in the majority of adult patients. 33 Whether the revascularization procedure in MMD induces covert structural changes remains unclear. In MMD, both diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) have provided in vivo measurements of microstructural changes