title: Hippocampal atrophy in relapsing-remitting and primary progressive MS: a comparative study.
abstract: BACKGROUND
  In multiple sclerosis (MS), demyelination and neuroaxonal damage are seen in the hippocampus, and MRI has revealed hippocampal atrophy.
  
  
  OBJECTIVE
  To investigate and compare hippocampal volume loss in patients with relapsing-remitting MS (RRMS) and primary progressive MS (PPMS) using manual volumetry, and explore its association with memory dysfunction.
  
  
  METHODS
  Hippocampi were manually delineated on volumetric MRI of 34 patients with RRMS, 23 patients with PPMS and 18 controls. Patients underwent neuropsychological tests of verbal and visuospatial recall memory. Linear regression was used to compare hippocampal volumes between subject groups, and to assess the association with memory function.
  
  
  RESULTS
  Hippocampal volumes were smaller in MS patients compared with controls, and were similar in patients with RRMS and PPMS. The mean decrease in hippocampal volume in MS patients was 317 mm(3) (9.4%; 95% CI 86 to 549; p = 0.008) on the right and 284 mm(3) (8.9%; 95% CI 61 to 508; p = 0.013) on the left. A borderline association of hippocampal volume with memory performance was observed only in patients with PPMS.
  
  
  CONCLUSIONS
  Hippocampal atrophy occurs in patients with RRMS and PPMS. Factors additional to hippocampal atrophy may impact on memory performance.
authors.affiliation: Department of Neuroinflammation, UCL Institute of Neurology, Queen Square, London, UK. v.anderson@ion.ucl.ac.uk
authors.forename: V M
authors.initials: VM
authors.lastname: Anderson
authors.forename: L K
authors.initials: LK
authors.lastname: Fisniku
authors.forename: Z
authors.initials: Z
authors.lastname: Khaleeli
authors.forename: M M
authors.initials: MM
authors.lastname: Summers
authors.forename: S A
authors.initials: SA
authors.lastname: Penny
authors.forename: D R
authors.initials: DR
authors.lastname: Altmann
authors.forename: A J
authors.initials: AJ
authors.lastname: Thompson
authors.forename: M A
authors.initials: MA
authors.lastname: Ron
authors.forename: D H
authors.initials: DH
authors.lastname: Miller
mesh_terms: D000328:Adult; D001284:Atrophy; D005260:Female; D006624:Hippocampus / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D016014:Linear Models; D008131:London; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory; D008569:Memory Disorders / Q000503:physiopathology / Q000523:psychology; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000473:pathology* / Q000503:physiopathology / Q000523:psychology; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000473:pathology* / Q000503:physiopathology / Q000523:psychology; D009483:Neuropsychological Tests; D018570:Risk Assessment; D012307:Risk Factors