title: Usefulness of contrast material in MR of patients with neurofibromatosis type 1.
abstract: OBJECTIVE
  Our objective was to determine the usefulness of routine administration of contrast material in brain MR imaging for the evaluation of areas of probable myelin vacuolization and neoplasms in patients with neurofibromatosis type 1 (NF-1).
  
  
  METHODS
  We retrospectively reviewed 112 consecutive contrast-enhanced brain MR studies obtained over a period of 7 years in 109 symptomatic and asymptomatic patients compiled from two institutional NF-1 data bases. MR studies were analyzed for areas of probable myelin vacuolization, with attention to degree of enhancement and its impact on lesion detection and characterization. Usefulness of contrast material was graded as 0 = not useful, 1+ = somewhat useful, and 2+ = useful.
  
  
  RESULTS
  Of 112 studies, 45% (n = 49) were normal. In the remaining 63 studies, 88 regions of probable myelin vacuolization and 52 tumors were identified. Enhancement was not observed in any regions of probable myelin vacuolization. Enhancement was present in 31% of tumors, and, of these, was found to be useful in 44%, somewhat useful in 12%, and not useful in 44%. For enhancing tumors, contrast agent was useful for lesion detection in 19% and for lesion characterization in 25%.
  
  
  CONCLUSIONS
  Contrast administration is useful in baseline MR studies to maximize tumor detection and characterization, to add confidence to the diagnosis of benign probable myelin vacuolization, and to document stability of neoplasms on follow-up examinations.
authors.affiliation: Department of Radiology, University of North Carolina, Chapel Hill 27599, USA.
authors.forename: C
authors.initials: C
authors.lastname: Bonawitz
authors.forename: M
authors.initials: M
authors.lastname: Castillo
authors.forename: C T
authors.initials: CT
authors.lastname: Chin
authors.forename: S K
authors.initials: SK
authors.lastname: Mukherji
authors.forename: A J
authors.initials: AJ
authors.lastname: Barkovich
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology; D002648:Child; D003287:Contrast Media; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009186:Myelin Sheath / Q000473:pathology; D009456:Neurofibromatosis 1 / Q000175:diagnosis*; D012189:Retrospective Studies; D014617:Vacuoles / Q000473:pathology
chemical_list: D003287:Contrast Media