title: Magnetic resonance diffusion tensor imaging (MRDTI) of the optic nerve and optic radiations at 3T in children with neurofibromatosis type I (NF-1).
abstract: BACKGROUND
  Optic pathway glioma (OPG) is a characteristic hallmark of neurofibromatosis type I (NF-I).
  
  
  OBJECTIVE
  To evaluate the feasibility of magnetic resonance diffusion tensor imaging (MRDTI) at 3T to detect abnormalities of the optic nerves and optic radiations in children with NF-I.
  
  
  METHODS
  3-T MRDTI was prospectively performed in 9 children with NF-I (7 boys, 2 girls, average age 7.8 years, range 3-17 years) and 44 controls (25 boys, 19 girls, average age 8.1 years, range 3-17 years). Fractional anisotropy (FA) and mean diffusivity were determined by region-of-interest analysis for the optic nerves and radiations. Statistical analysis compared controls to NF-I patients.
  
  
  RESULTS
  Two NF-I patients had bilateral optic nerve gliomas, three had chiasmatic gliomas and four had unidentified neurofibromatosis objects (UNOs) along the optic nerve pathways. All NF-I patients had statistically significant decreases in FA and elevations in mean diffusivity in the optic nerves and radiations compared to age-matched controls.
  
  
  CONCLUSIONS
  MRDTI can evaluate the optic pathways in children with NF-I. Statistically significant abnormalities were detected in the diffusion tensor metrics of the optic nerves and radiations in children with NF-I compared to age-matched controls.
authors.affiliation: Department of Radiology, University of Vermont School of Medicine-FAHC, 111 Colchester Ave, Burlington, VT 05401, USA. Christopher.filippi@vtmednet.org
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Filippi
authors.forename: Aaron
authors.initials: A
authors.lastname: Bos
authors.forename: Joshua P
authors.initials: JP
authors.lastname: Nickerson
authors.forename: Michael B
authors.initials: MB
authors.lastname: Salmela
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Koski
authors.forename: Keith A
authors.initials: KA
authors.lastname: Cauley
mesh_terms: D000293:Adolescent; D016880:Anisotropy; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D009456:Neurofibromatosis 1 / Q000473:pathology*; D009900:Optic Nerve / Q000473:pathology*; D020339:Optic Nerve Glioma / Q000473:pathology*; D011446:Prospective Studies; D015203:Reproducibility of Results