title: An elastically compressible phantom material with mechanical and x-ray attenuation properties equivalent to breast tissue.
abstract: We have developed a novel phantom material: a solution of polyvinyl alcohol (PVAL) in ethanol and water, freeze-thawed to produce a solid yet elastically compressible gel. The x-ray attenuation and mechanical properties of these gels are compared with published measurements of breast tissue. Gels with PVAL concentrations from 5 to 20% w/v were produced. The linear x-ray attenuation coefficients of these gels range from 0.76 to 0.86 cm(-1) at 17.5 keV, increasing with PVAL concentration. These values are very similar to the published values of breast tissue at this energy, 0.8-0.9 cm(-1). Under compression cancerous breast tissue is approximately ten times stiffer than healthy breast tissue. The Young's moduli of the gels increase with PVAL concentration. Varying the PVAL concentration from 7.5 to 20% w/v produces gels with Young's moduli from 20 to 220 kPa at 15% strain. These values are characteristic of normal and cancerous breast tissue, respectively.
authors.affiliation: Department of Medical Physics and Bioengineering, University College London, London WC1E 6BT, UK. bprice@medphys.ucl.ac.uk
authors.forename: B D
authors.initials: BD
authors.lastname: Price
authors.forename: A P
authors.initials: AP
authors.lastname: Gibson
authors.forename: L T
authors.initials: LT
authors.lastname: Tan
authors.forename: G J
authors.initials: GJ
authors.lastname: Royle
mesh_terms: D000818:Animals; D001940:Breast / Q000502:physiology* / Q000503:physiopathology; D001943:Breast Neoplasms / Q000503:physiopathology; D055119:Elastic Modulus; D004548:Elasticity; D000431:Ethanol / Q000528:radiation effects; D005260:Female; D005615:Freezing; D005782:Gels / Q000528:radiation effects*; D006801:Humans; D008327:Mammography / Q000295:instrumentation*; D019216:Metals, Heavy / Q000528:radiation effects; D008954:Models, Biological; D019047:Phantoms, Imaging; D011142:Polyvinyl Alcohol / Q000528:radiation effects*; D012492:Salts / Q000528:radiation effects; D013552:Swine
chemical_list: D005782:Gels; D019216:Metals, Heavy; D012492:Salts; D000431:Ethanol; D011142:Polyvinyl Alcohol