title: MR imaging of the corpus callosum in pediatric patients with neurofibromatosis type 1.
abstract: OBJECTIVE
  Many pediatric patients with neurofibromatosis type 1 (NF-1) have an apparent increased thickness of the corpus callosum (CC) on sagittal T1-weighted images compared with patients not affected by NF-1. In this study, we compared the surface area of the CC in children with NF-1 with that of healthy pediatric control subjects to determine if this was another common intracranial manifestation of NF-1.
  
  
  METHODS
  Midsagittal T1-weighted MR images of 43 consecutive children with NF-1 and 43 age- and gender-matched healthy control subjects were reviewed retrospectively. The surface area of the CC and the midsagittal intracranial skull surface (MISS) area were measured five times each on all midsagittal images. A mean CC to mean midline intracranial surface area ratio (CC/MISS) was calculated for each.
  
  
  RESULTS
  There is a statistically significant increase in the mean CC surface area in pediatric patients with NF-1 (680 mm2 +/- 98, range 509-974 mm2) compared with control subjects (573 mm2 +/- 83, range 404-797 mm2). The mean MISS is significantly increased in patients with NF-1 (16568 mm2 +/- 1161, range 14107-19394 mm2 vs 15402 mm2 +/- 1133, range 12951-17905 mm2 for control subjects). CC/MISS was also significantly increased in the patients with NF-1 relative to the control subjects (.0410 +/- .0043, range .0330-.0530 vs .0372 +/- .0043, range .0270-.0470 for control subjects).
  
  
  CONCLUSIONS
  A larger midsagittal surface area of the CC is another intracranial manifestation of NF-1 that can be demonstrated by sagittal MR imaging. The etiology is unclear, but could be related to abnormal neurofibromin and Ras protein activity. Potential clinical relevance is discussed herein.
authors.affiliation: Department of Diagnostic Imaging and Radiology, Children's National Medical Center, Washington, DC 20010-2970, USA.
authors.forename: E C
authors.initials: EC
authors.lastname: Dubovsky
authors.forename: T N
authors.initials: TN
authors.lastname: Booth
authors.forename: G
authors.initials: G
authors.lastname: Vezina
authors.forename: C A
authors.initials: CA
authors.lastname: Samango-Sprouse
authors.forename: K M
authors.initials: KM
authors.lastname: Palmer
authors.forename: C O
authors.initials: CO
authors.lastname: Brasseux
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003337:Corpus Callosum / Q000473:pathology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009456:Neurofibromatosis 1 / Q000175:diagnosis*; D012016:Reference Values; D012189:Retrospective Studies; D012886:Skull / Q000473:pathology