title: Relevance of hypointense brain MRI lesions for long-term worsening of clinical disability in relapsing multiple sclerosis.
abstract: BACKGROUND
  The accrual of brain focal pathology is considered a good substrate of disability in relapsing-remitting multiple sclerosis (RRMS). However, knowledge on long-term lesion evolution and its relationship with disability progression is poor.
  
  
  OBJECTIVE
  The objective of this paper is to evaluate in RRMS the long-term clinical relevance of brain lesion evolution.
  
  
  METHODS
  In 58 RRMS patients we acquired, using the same scanner and protocol, brain magnetic resonance imaging (MRI) at baseline and 10±0.5 years later. MRI data were correlated with disability changes as measured by the Expanded Disability Status Scale (EDSS).
  
  
  RESULTS
  The annualized 10-year lesion volume (LV) growth was +0.25±0.5 cm(3) (+6.7±8.7%) for T2-weighted (T2-W) lesions and +0.20±0.31 cm(3) (+11.5±12.3%) for T1-weighted (T1-W) lesions. The univariate analysis showed moderate correlations between baseline MRI measures and EDSS at 10 years (p < 0.001). Also, 10-year EDSS worsening correlated with LV growth and the number of new/enlarging lesions measured over the same period (p < 0.005). In the stepwise multiple regression analysis, EDSS worsening over 10 years was best correlated with the combination of baseline T1-W lesion count and increasing T1-W LV (R = 0.61, p < 0.001).
  
  
  CONCLUSIONS
  In RRMS patients, long-term brain lesion accrual is associated with worsening in clinical disability. This is particularly true for hypointense, destructive lesions.
authors.affiliation: Department of Neurological and Behavioral Sciences, University of Siena, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Giorgio
authors.forename: Maria Laura
authors.initials: ML
authors.lastname: Stromillo
authors.forename: Maria Letizia
authors.initials: ML
authors.lastname: Bartolozzi
authors.forename: Francesca
authors.initials: F
authors.lastname: Rossi
authors.forename: Marco
authors.initials: M
authors.lastname: Battaglini
authors.forename: Alessandro
authors.initials: A
authors.lastname: De Leucio
authors.forename: Leonello
authors.initials: L
authors.lastname: Guidi
authors.forename: Patrizia
authors.initials: P
authors.lastname: Maritato
authors.forename: Emilio
authors.initials: E
authors.lastname: Portaccio
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Sormani
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Amato
authors.forename: Nicola
authors.initials: N
authors.lastname: De Stefano
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology*; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000150:complications* / Q000473:pathology*; D013997:Time Factors
keywords: MRI; Multiple sclerosis; brain lesions; disability; longitudinal