title: One year follow up study of primary and transitional progressive multiple sclerosis.
abstract: OBJECTIVE
  To document clinical and magnetic resonance imaging (MRI) characteristics of a large cohort of primary and transitional progressive multiple sclerosis (PP and TP MS) patients over one year.
  
  
  BACKGROUND
  Patients with PP or TP MS have been shown to have low brain T2 and T1 lesion loads and slow rates of new lesion formation with minimal gadolinium enhancement, despite their accumulating disability. Serial evaluation of these patients is needed to elucidate the pathological processes responsible for disease progression and to identify clinical and MRI measures which can monitor these processes in treatment trials.
  
  
  METHODS
  Patients, recruited from six European centres, underwent two assessments on the expanded disability status scale (EDSS) and MRI of the brain and spinal cord, 1 year apart.
  
  
  RESULTS
  Of the 167 patients studied (137 with PP MS and 30 with TP MS), 41 (25%; 35 PP and six TP) showed a one step increase in the EDSS. The mean number of new brain lesions seen was 0.88 in the PP group and 0.47 in the TP MS group. Both groups demonstrated change in T2 lesion load over the year (p< or =0.002), with median percentage changes of 7.3% in the PP group and 10. 8% in the TP MS group. The PP group also showed a significant change in T1 load (p< 0.001, median change 12.6%). The number of new cord lesions seen was small (mean of 0.14 in the PP group and no new cord lesions in the TP group). Both groups demonstrated a decrease in cord cross sectional area (p< 0.001, median changes; PP 3.8%, TP 4. 9%), but only the PP group showed evidence of significant brain atrophy (p<0.001, 0.95%).
  
  
  CONCLUSIONS
  Although the monitoring of disease progression in this patient group is difficult, this study demonstrates changes in both lesion load and atrophy, which, if shown to correlate with clinical change over a longer time will facilitate therapeutic trial design.
authors.affiliation: NMR Research Unit, Institute of Neurology, Queen Square, London WC1 N3BG, UK.
authors.forename: V L
authors.initials: VL
authors.lastname: Stevenson
authors.forename: D H
authors.initials: DH
authors.lastname: Miller
authors.forename: S M
authors.initials: SM
authors.lastname: Leary
authors.forename: M
authors.initials: M
authors.lastname: Rovaris
authors.forename: F
authors.initials: F
authors.lastname: Barkhof
authors.forename: B
authors.initials: B
authors.lastname: Brochet
authors.forename: V
authors.initials: V
authors.lastname: Dousset
authors.forename: M
authors.initials: M
authors.lastname: Filippi
authors.forename: R
authors.initials: R
authors.lastname: Hintzen
authors.forename: X
authors.initials: X
authors.lastname: Montalban
authors.forename: C H
authors.initials: CH
authors.lastname: Polman
authors.forename: A
authors.initials: A
authors.lastname: Rovira
authors.forename: J
authors.initials: J
authors.lastname: de Sa
authors.forename: A J
authors.initials: AJ
authors.lastname: Thompson
mesh_terms: D001284:Atrophy; D001921:Brain / Q000473:pathology; D015331:Cohort Studies; D004185:Disability Evaluation; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D020528:Multiple Sclerosis, Chronic Progressive / Q000175:diagnosis*; D009460:Neurologic Examination; D013116:Spinal Cord / Q000473:pathology