title: Development of a phantom to test fully automated breast density software - A work in progress.
abstract: OBJECTIVE
  Mammographic density (MD) is an independent risk factor for breast cancer and may have a future role for stratified screening. Automated software can estimate MD but the relationship between breast thickness reduction and MD is not fully understood. Our aim is to develop a deformable breast phantom to assess automated density software and the impact of breast thickness reduction on MD.
  
  
  METHODS
  Several different configurations of poly vinyl alcohol (PVAL) phantoms were created. Three methods were used to estimate their density. Raw image data of mammographic images were processed using Volpara to estimate volumetric breast density (VBD%); Hounsfield units (HU) were measured on CT images; and physical density (g/cm3) was calculated using a formula involving mass and volume. Phantom volume versus contact area and phantom volume versus phantom thickness was compared to values of real breasts.
  
  
  RESULTS
  Volpara recognized all deformable phantoms as female breasts. However, reducing the phantom thickness caused a change in phantom density and the phantoms were not able to tolerate same level of compression and thickness reduction experienced by female breasts during mammography.
  
  
  CONCLUSIONS
  Our results are promising as all phantoms resulted in valid data for automated breast density measurement. Further work should be conducted on PVAL and other materials to produce deformable phantoms that mimic female breast structure and density with the ability of being compressed to the same level as female breasts.
  
  
  CONCLUSIONS
  We are the first group to have produced deformable phantoms that are recognized as breasts by Volpara software.
authors.affiliation: Department of Life Sciences and Health, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, Box 4, St. Olavs Plass, 0130 Oslo, Norway; School of Health Sciences, University of Salford, Salford M6 6PU, Greater Manchester, UK.
authors.forename: G G
authors.initials: GG
authors.lastname: Waade
authors.affiliation: Department of Life Sciences and Health, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, Box 4, St. Olavs Plass, 0130 Oslo, Norway; The Cancer Registry of Norway, P.O. 5313 Majorstuen, 0304 Oslo, Norway. Electronic address: solveig.hofvind@kreftregisteret.no.
authors.forename: S
authors.initials: S
authors.lastname: Hofvind
authors.affiliation: School of Health Sciences, University of Salford, Salford M6 6PU, Greater Manchester, UK; Radiology Department, University Hospitals of Morecambe Bay NHS Foundation Trust, Barrow-in-Furness, Cumbria, UK.
authors.forename: J D
authors.initials: JD
authors.lastname: Thompson
authors.affiliation: Volpara Solutions Limited, P.O. Box 24404, Manners St Central, Wellington 6142, New Zealand.
authors.forename: R
authors.initials: R
authors.lastname: Highnam
authors.affiliation: School of Health Sciences, University of Salford, Salford M6 6PU, Greater Manchester, UK; Karolinska Institute, Stockholm, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Hogg
mesh_terms: D000071060:Breast Density; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008327:Mammography; D019047:Phantoms, Imaging; D010865:Pilot Projects; D011142:Polyvinyl Alcohol; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D012984:Software; D014057:Tomography, X-Ray Computed
chemical_list: D011142:Polyvinyl Alcohol
keywords: Breast compression; Deformable phantoms; Mammography; Validation