title: The state of the art in breast imaging using the Twente Photoacoustic Mammoscope: results from 31 measurements on malignancies.
abstract: OBJECTIVE
  Photoacoustic mammography is potentially an ideal technique, however, the amount of patient data is limited. To further our understanding of the in vivo performance of the method and to guide further research and development, we imaged 33 breast malignancies using the research system - the Twente Photoacoustic Mammoscope (PAM).
  
  
  METHODS
  Thirty-one patients participated in this retrospective, observational study. The study and informed consent procedure were approved by the local ethics committee. PAM uses 1,064 nm light for excitation with a planar, 588-element, 1-MHz ultrasound array for detection. Photoacoustic lesion visibility and appearance were compared with conventional imaging (x-ray mammography and ultrasonography) findings, histopathology and patient demographics.
  
  
  RESULTS
  Of 33 malignancies 32 were visualized with high contrast and good co-localization with conventional imaging. The contrast of the detected malignancies was independent of radiographic breast density, and size estimation was reasonably good with an average 28 % deviation from histology. However, the presence of contrast areas outside the malignant region is suggestive for low specificity of the current system. Statistical analyses did not reveal any further relationship between PAM results and patient demographics nor lesion characteristics.
  
  
  CONCLUSIONS
  The results confirm the high potential of photoacoustic mammography in future breast care.
  
  
  CONCLUSIONS
  • Photoacoustic breast imaging visualizes malignancies with high imaging contrast. • Photoacoustic lesion contrast is independent of the mammographically estimated breast density. • No clear relationship exists between photoacoustic characteristics and lesion type, grade, etc. • Photoacoustic specificity to breast cancer from some cases is not yet optimal.
authors.affiliation: Biomedical Photonic Imaging Group, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.|Center for Breast Care, Medisch Spectrum Twente, P.O. Box 50.000, 7500 KA, Enschede, The Netherlands.
authors.forename: Michelle
authors.initials: M
authors.lastname: Heijblom
authors.affiliation: Biomedical Photonic Imaging Group, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.
authors.forename: Daniele
authors.initials: D
authors.lastname: Piras
authors.affiliation: Center for Breast Care, Medisch Spectrum Twente, P.O. Box 50.000, 7500 KA, Enschede, The Netherlands.
authors.forename: Frank M
authors.initials: FM
authors.lastname: van den Engh
authors.affiliation: Center for Breast Care, Medisch Spectrum Twente, P.O. Box 50.000, 7500 KA, Enschede, The Netherlands.
authors.forename: Margreet
authors.initials: M
authors.lastname: van der Schaaf
authors.affiliation: Center for Breast Care, Medisch Spectrum Twente, P.O. Box 50.000, 7500 KA, Enschede, The Netherlands.
authors.forename: Joost M
authors.initials: JM
authors.lastname: Klaase
authors.affiliation: Biomedical Photonic Imaging Group, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.
authors.forename: Wiendelt
authors.initials: W
authors.lastname: Steenbergen
authors.affiliation: Biomedical Photonic Imaging Group, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands. s.manohar@utwente.nl.
authors.forename: Srirang
authors.initials: S
authors.lastname: Manohar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000473:pathology; D000071960:Breast Carcinoma In Situ / Q000000981:diagnostic imaging*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008327:Mammography / Q000295:instrumentation* / Q000379:methods; D008875:Middle Aged; D061088:Photoacoustic Techniques / Q000295:instrumentation* / Q000379:methods; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
keywords: Breast neoplasms; Diagnostic imaging; Photoacoustic techniques; Pulsed lasers; Ultrasound