title: Developing easy to perform routine MRI measurements as potential surrogates for cognitive impairment in MS.
abstract: OBJECTIVE
  One of the most frequently disabling symptoms in Multiple Sclerosis (MS) is cognitive impairment which is often insidious in onset and therefore difficult to recognize in the early stages, for both persons with MS and clinicians. A biomarker that would help identify those at risk of cognitive impairment, or with only mild impairment, would be a useful tool for clinicians. Using MRI, already an integral tool in the diagnosis and monitoring of disease activity in MS, would be ideal. Thus, this study aimed to determine if simple measures on routine MRI could serve as potential biomarkers for cognitive impairment in MS.
  
  
  METHODS
  We retrospectively identified 51 persons with MS who had a cognitive assessment and MRI within six months of the MRI. Simple linear measurements of the hippocampi, bifrontral and third ventricular width, bicaudate width and the anterior, mid and posterior corpus callosum were made. Pearson's correlations examined the relationship between these MRI measures and cognitive tests, and MRI measures were compared in persons with MS who were either normal or cognitively impaired on objective cognitive tests using Analysis of Covariance (ANCOVA).
  
  
  RESULTS
  Bicaudate span and third ventricular width were both negatively correlated, while corpus callosal measures were positive correlated with cognitive test performance. After controlling for potential confounders, bicaudate span was significant different on measures of immediate recall. Both anterior and posterior corpus collosal measure were significantly different on measures of verbal fluency, immediate recall and higher executive function; while the anterior corpus callosum was also significantly different on processing speed. The middle corpus collosal measure was significantly different on immediate recall and higher executive function.
  
  
  CONCLUSIONS
  This study presents data demonstrating that simple to apply MRI measures of atrophy may serve as biomarkers for cognitive impairment in persons with MS. Further prospective studies are needed to validate these findings.
authors.affiliation: University of Western Ontario (Western), London Health Sciences Center, University Hospital, Department of Clinical Neurological Sciences, LHSC-UH, 339 Windermere Road, London, ON N5A 5A5, Canada; St. Joseph's Health Care, Parkwood Institute, Department of Cognitive Neurology, 550 Wellington Road, London, ON N6C 0A7, Canada. Electronic address: Sarah.morrow@lhsc.on.ca.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Morrow
authors.affiliation: University of Western Ontario (Western), London Health Sciences Center, University Hospital, Department of Clinical Neurological Sciences, LHSC-UH, 339 Windermere Road, London, ON N5A 5A5, Canada; Present Address: McMaster University, Hamilton General Hospital, 237 Barton Street East, Department of Medicine, Division of Neurology, Hamilton, ON L8L 2X2, Canada.
authors.forename: Suresh
authors.initials: S
authors.lastname: Menon
authors.affiliation: University of Western Ontario (Western), London Health Sciences Center, University Hospital, Department of Clinical Neurological Sciences, LHSC-UH, 339 Windermere Road, London, ON N5A 5A5, Canada.
authors.forename: Heather
authors.initials: H
authors.lastname: Rosehart
authors.affiliation: University of Western Ontario (Western), London Health Sciences Center, University Hospital, Department of Radiology/Medical Imaging, LHSC-UH, 339 Windermere Road B10-006, London, ON N5A 5A5, Canada.
authors.forename: Manas
authors.initials: M
authors.lastname: Sharma
mesh_terms: D000328:Adult; D001284:Atrophy / Q000000981:diagnostic imaging; D015415:Biomarkers; D002552:Cerebral Ventricles / Q000000981:diagnostic imaging*; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging* / Q000209:etiology; D003337:Corpus Callosum / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications / Q000000981:diagnostic imaging*; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers
keywords: Atrophy; Biomarker; Cognitive impairment; MRI; Multiple sclerosis