title: Quantitative analysis of breast parenchymal density: correlation with women's age.
abstract: OBJECTIVE
  The authors evaluated the relationship between a woman's breast parenchymal density and her age by means of a quantitative method for measuring density from digitized mammograms.
  
  
  METHODS
  The percentage of the breast considered to be dense was evaluated from mammograms of 50 women stratified by age. Quantitative analysis based on the computer segmentation of tissue in digitized mammograms was performed by three expert mammographers. The results of this analysis were compared with results from a review of the film mammograms by three expert mammographers.
  
  
  RESULTS
  A slight decrease in the percentage of breast considered to be dense with increased age was observed. The average difference in the percentage of dense breast tissue between the youngest and the oldest age groups was 6.4% based on the digital review and 14.6% based on the film review. Within each age group, the total variability was on the order of 75%.
  
  
  CONCLUSIONS
  The difference in mean magnitude between the youngest and oldest age groups was small and may not be clinically important. The variability within an age group was large, which suggests that age is not a reliable indicator of percentage of dense breast tissue.
authors.affiliation: Department of Biomedical Engineering, Lerner Research Institute, The Cleveland Clinic Foundation, OH 44195, USA.
authors.forename: K A
authors.initials: KA
authors.lastname: Powell
authors.forename: N A
authors.initials: NA
authors.lastname: Obuchowski
authors.forename: W J
authors.initials: WJ
authors.lastname: Davros
authors.forename: W A
authors.initials: WA
authors.lastname: Chilcote
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D005260:Female; D006801:Humans; D008327:Mammography; D008875:Middle Aged; D011856:Radiographic Image Enhancement