title: Diffusion tensor imaging suggests extrapontine extension of pediatric diffuse intrinsic pontine gliomas.
abstract: OBJECTIVE
  To apply DTI to detect early extrapontine extension of pediatric diffuse intrinsic pontine glioma along the corticospinal tracts.
  
  
  METHODS
  In children with diffuse intrinsic pontine glioma, low-grade brainstem glioma, and age-matched controls, DTI metrics were measured in the posterior limb of the internal capsule and posterior centrum semiovale. Histological examination was available in one patient.
  
  
  RESULTS
  6 diffuse intrinsic pontine glioma, 8 low-grade brainstem glioma, and two groups of 25 controls were included. In diffuse intrinsic pontine glioma compared to controls, fractional anisotropy was lower in the bilateral posterior limb of the internal capsule, axial diffusivity was lower in the bilateral posterior centrum semiovale and posterior limb of the internal capsule, while radial diffusivity was higher in the bilateral posterior limb of the internal capsule. No significant differences were found between low-grade brainstem glioma and controls. In diffuse intrinsic pontine glioma compared to low-grade brainstem glioma, axial diffusivity was lower in the bilateral posterior limb of the internal capsule. Histological examination in one child showed tumor cells in the posterior limb of the internal capsule.
  
  
  CONCLUSIONS
  Reduction in fractional anisotropy and axial diffusivity and increase in radial diffusivity in diffuse intrinsic pontine glioma may reflect tumor extension along the corticospinal tracts as shown by histology. DTI may detect early extrapontine tumor extension in diffuse intrinsic pontine glioma before it becomes apparent on conventional MRI sequences.
authors.affiliation: Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Matthias W
authors.initials: MW
authors.lastname: Wagner
authors.affiliation: Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: W Robert
authors.initials: WR
authors.lastname: Bell
authors.affiliation: Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Kern
authors.affiliation: Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Thangamadhan
authors.initials: T
authors.lastname: Bosemani
authors.affiliation: Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Joyce
authors.initials: J
authors.lastname: Mhlanga
authors.affiliation: Department of Epidemiology, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Division of General Internal Medicine, Department of Medicine, The Johns Hopkins School of Medicine, Baltimore, Maryland, USA.
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Carson
authors.affiliation: Division of Pediatric Oncology, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Cohen
authors.affiliation: Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Division of Pediatric Oncology, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Eric H
authors.initials: EH
authors.lastname: Raabe
authors.affiliation: Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Fausto
authors.initials: F
authors.lastname: Rodriguez
authors.affiliation: Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Thierry A G M
authors.initials: TA
authors.lastname: Huisman
authors.affiliation: Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA. Electronic address: aporett1@jhmi.edu.
authors.forename: Andrea
authors.initials: A
authors.lastname: Poretti
mesh_terms: D016880:Anisotropy; D020295:Brain Stem Neoplasms / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D005910:Glioma / Q000473:pathology*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012189:Retrospective Studies
keywords: Children; Corticospinal tract; Diffuse intrinsic pontine glioma; Diffusion tensor imaging; Extrapontine extension; Neuroimaging