title: Diffusion tensor fiber tractography for arteriovenous malformations: quantitative analyses to evaluate the corticospinal tract and optic radiation.
abstract: OBJECTIVE
  We hypothesized that diffusion tensor fiber tractography would be affected by intracranial arteriovenous malformation (AVM). The purpose of the present study was to evaluate the influence of intracranial AVM on corticospinal tract and optic radiation tractography.
  
  
  METHODS
  The subject group comprised 34 patients with untreated intracranial AVM. Hemorrhage was present in 13 patients and absent in 21 patients. Perinidal fractional anisotropy (FA) and number of voxels along the reconstructed corticospinal and optic radiation tracts were measured, and left-to-right asymmetry indices (AIs) for those values were quantified. Patients were assigned to 1 of 3 groups: tracts distant from nidus, tracts close to nidus without neurologic symptoms, and tracts close to nidus associated with neurologic symptoms. One-way analysis of variance was used to compare differences in AI between groups. Hemorrhagic and nonhemorrhagic groups were assessed separately.
  
  
  RESULTS
  In patients without hemorrhage, AI of optic radiation volume (P<.0001), AI of perinidal FA along corticospinal tract (P=.006), and optic radiation (P=.01) differed significantly between groups. In patients associated with hemorrhage, AI of corticospinal tract volume (P=.01), AI of perinidal FA along corticospinal tract (P=.04), and optic radiation (P=.004) differed significantly between groups.
  
  
  CONCLUSIONS
  Corticospinal tract and optic radiation tractography were visualized in patients with AVM. In patients with both hemorrhagic and nonhemorrhagic AVM, the 2 fiber tracts close to the nidus were less visualized in the affected hemisphere than those distant from the nidus. Tracts were less visualized in patients with neurologic symptoms than in asymptomatic patients.
authors.affiliation: Department of Diagnostic Imaging & Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Okada
authors.forename: Y
authors.initials: Y
authors.lastname: Miki
authors.forename: K
authors.initials: K
authors.lastname: Kikuta
authors.forename: N
authors.initials: N
authors.lastname: Mikuni
authors.forename: S
authors.initials: S
authors.lastname: Urayama
authors.forename: Y
authors.initials: Y
authors.lastname: Fushimi
authors.forename: A
authors.initials: A
authors.lastname: Yamamoto
authors.forename: N
authors.initials: N
authors.lastname: Mori
authors.forename: H
authors.initials: H
authors.lastname: Fukuyama
authors.forename: N
authors.initials: N
authors.lastname: Hashimoto
authors.forename: K
authors.initials: K
authors.lastname: Togashi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000465:Algorithms; D002648:Child; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D002538:Intracranial Arteriovenous Malformations / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009900:Optic Nerve / Q000473:pathology*; D011712:Pyramidal Tracts / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014795:Visual Pathways / Q000473:pathology