title: In vivo quantitative imaging of normal and cancerous breast tissue using broadband diffuse optical tomography.
abstract: OBJECTIVE
  A NIR tomography system that combines frequency domain (FD) and continuous wave (CW) measurements was used to image normal and malignant breast tissues.
  
  
  METHODS
  FD acquisitions were confined to wavelengths less than 850 nm because of detector limitations, whereas light from longer wavelengths (up to 948 nm) was measured in CW mode with CCD-coupled spectrometer detection. The two data sets were combined and processed in a single spectrally constrained reconstruction to map concentrations of hemoglobin, water, and lipid, as well as scattering parameters in the breast.
  
  
  RESULTS
  Chromophore concentrations were imaged in the breasts of nine asymptomatic volunteers to evaluate their intrasubject and intersubject variability. Normal subject data showed physiologically expected trends. Images from three cancer patients indicate that the added CW data is critical to recovering the expected increases in water and decreases in lipid content within malignancies. Contrasts of 1.5 to twofold in hemoglobin and water values were found in cancers.
  
  
  CONCLUSIONS
  In vivo breast imaging with instrumentation that combines FD and CW NIR data acquisition in a single spectral reconstruction produces more accurate hemoglobin, water, and lipid results relative to FD data alone.
authors.affiliation: Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755, USA. wang.jia2@mayo.edu
authors.forename: Jia
authors.initials: J
authors.lastname: Wang
authors.forename: Shudong
authors.initials: S
authors.lastname: Jiang
authors.forename: Zhongze
authors.initials: Z
authors.lastname: Li
authors.forename: Roberta M
authors.initials: RM
authors.lastname: diFlorio-Alexander
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Barth
authors.forename: Peter A
authors.initials: PA
authors.lastname: Kaufman
authors.forename: Brian W
authors.initials: BW
authors.lastname: Pogue
authors.forename: Keith D
authors.initials: KD
authors.lastname: Paulsen
mesh_terms: D001940:Breast / Q000166:cytology* / Q000378:metabolism / Q000473:pathology*; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D050356:Lipid Metabolism; D008279:Magnetic Resonance Imaging; D041622:Tomography, Optical / Q000379:methods*; D014867:Water / Q000378:metabolism
chemical_list: D014867:Water