title: MRI characteristics of the MLF in MS patients with chronic internuclear ophthalmoparesis.
abstract: OBJECTIVE
  The authors imaged the medial longitudinal fasciculus (MLF) in 58 patients with MS and chronic internuclear ophthalmoparesis (INO) to determine which MRI technique best shows the characteristic lesion associated with this ocular motor syndrome.
  
  
  METHODS
  Using quantitative infrared oculography, the authors determined the ratios of abduction to adduction for velocity and acceleration, to confirm the presence of INO and to determine the severity of MLF dysfunction in 58 patients with MS and INO. Conventional MRI techniques, including proton density imaging (PDI), T2-weighted imaging, and fluid-attenuated inversion recovery (FLAIR) imaging, were used to ascertain which technique best shows MLF lesions within the brainstem tegmentum. T1-weighted imaging was performed to determine the frequency of brainstem tegmentum hypointensities.
  
  
  RESULTS
  All patients studied had evidence of an MLF lesion hyperintensity on PDI, whereas T2-weighted imaging and FLAIR imaging showed these lesions in 88% and 48% of patients, respectively. With PDI, dorsomedial tegmentum lesions were seen in the pons in 93% of patients and in the midbrain of 66% of patients. Lesions were observed at both locations in 59% of patients. One patient had an MLF lesion with a corresponding T1 hypointensity.
  
  
  CONCLUSIONS
  PDI best shows the MLF lesion in patients with MS and INO.
authors.affiliation: Department of Neurology, University of Texas Southwestern Medical Center, Dallas 02115, USA. efrohm@mednet.swmed.edu
authors.forename: E M
authors.initials: EM
authors.lastname: Frohman
authors.forename: H
authors.initials: H
authors.lastname: Zhang
authors.forename: P D
authors.initials: PD
authors.lastname: Kramer
authors.forename: J
authors.initials: J
authors.lastname: Fleckenstein
authors.forename: K
authors.initials: K
authors.lastname: Hawker
authors.forename: M K
authors.initials: MK
authors.lastname: Racke
authors.forename: T C
authors.initials: TC
authors.lastname: Frohman
mesh_terms: D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008636:Mesencephalon / Q000473:pathology*; D009103:Multiple Sclerosis / Q000175:diagnosis*; D015835:Ocular Motility Disorders / Q000175:diagnosis*; D011149:Pons / Q000473:pathology; D012438:Saccades