title: Initial clinical experience with microwave breast imaging in women with normal mammography.
abstract: OBJECTIVE
  We have developed a microwave tomography system for experimental breast imaging.
  
  
  METHODS
  In this article, we illustrate a strategy for optimizing the coupling liquid for the antenna array based on in vivo measurement data. We present representative phantom experiments to illustrate the imaging system's ability to recover accurate property distributions over the range of dielectric properties expected to be encountered clinically. To demonstrate clinical feasibility and assess the microwave properties of the normal breast in vivo, we summarize our initial experience with microwave breast exams of 43 women with negative mammography according to the Breast Imaging Reporting and Data System (BI-RADS 1).
  
  
  RESULTS
  The clinical results show a high degree of bilateral symmetry in the whole breast average microwave properties. Focal assessments of microwave properties are associated with breast tissue composition evaluated through radiographic density categorization verified through magnetic resonance image correlation in selected cases. Specifically, both whole-breast average and local microwave properties increase with increasing radiographic density, in which the latter exhibits a more substantial rise.
  
  
  CONCLUSIONS
  These findings support our hypothesis that water content variations in the breast play an influential role in dictating the overall dielectric property distributions and indicate that the microwave properties in the breast are more heterogeneous than previously believed based on ex vivo property measurements reported in the literature.
authors.affiliation: Thayer School of Engineering, HB 800, Dartmouth College, Hanover, NH 03755, USA. paul.meaney@dartmouth.edu
authors.forename: Paul M
authors.initials: PM
authors.lastname: Meaney
authors.forename: Margaret W
authors.initials: MW
authors.lastname: Fanning
authors.forename: Timothy
authors.initials: T
authors.lastname: Raynolds
authors.forename: Colleen J
authors.initials: CJ
authors.lastname: Fox
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Fang
authors.forename: Christine A
authors.initials: CA
authors.lastname: Kogel
authors.forename: Steven P
authors.initials: SP
authors.lastname: Poplack
authors.forename: Keith D
authors.initials: KD
authors.lastname: Paulsen
mesh_terms: D000328:Adult; D000368:Aged; D001941:Breast Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008327:Mammography; D008872:Microwaves; D008875:Middle Aged; D019047:Phantoms, Imaging