title: Progression of corpus callosum atrophy in early stage of Alzheimer's disease: MRI based study.
abstract: OBJECTIVE
  Magnetic resonance imaging (MRI) studies reveal that atrophy of the corpus callosum (CC) is involved in early Alzheimer's disease (AD). The aim of this study was to investigate when and how callosal changes occur in the early course of AD.
  
  
  METHODS
  The Open Access Series of Imaging Studies data sets were used in this study to investigate callosal change. High-resolution structural MRI was performed in 196 older patients. Subjects were characterized using the Clinical Dementia Rating (CDR); 98 healthy controls were not demented (CDR 0), and 98 patients had clinical diagnosis of AD in the very mild dementia stage (CDR 0.5; n = 70) and the mild dementia stage (CDR 1; n = 28). A semiautomatic segmentation method was used to extract the CC in the midsagittal plane. The total and regional areas of the CC were measured.
  
  
  RESULTS
  The results indicated that callosal atrophy occurred in when subjects' CDRs were 0.5. The area of the genu and rostral body of the CC in the healthy controls (CDR 0) was significantly different from that of the subjects with very mild dementia (CDR 0.5) (P < .05). A significant difference could also be found in the area of the rostral body and midbody of the CC between subjects with very mild dementia (CDR 0.5) and those with mild dementia (CDR 1) (P < .05).
  
  
  CONCLUSIONS
  Callosal atrophy can be detected in subjects with CDRs of 0.5. The change in the CC in the early stage of AD indicates an anterior-to-posterior atrophic process as the degree of dementia assessed by the CDR (from 0 to 0.5 to 1) increases.
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China.
authors.forename: Minwei
authors.initials: M
authors.lastname: Zhu
authors.forename: Wenpeng
authors.initials: W
authors.lastname: Gao
authors.forename: Xudong
authors.initials: X
authors.lastname: Wang
authors.forename: Chen
authors.initials: C
authors.lastname: Shi
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Lin
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000473:pathology*; D001284:Atrophy / Q000473:pathology; D015897:Comorbidity; D003337:Corpus Callosum / Q000473:pathology*; D003704:Dementia / Q000453:epidemiology* / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D038622:Internationality; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D017678:Sex Distribution