title: A multichannel time-domain scanning fluorescence mammograph: performance assessment and first in vivo results.
abstract: We present a scanning time-domain fluorescence mammograph capable to image the distribution of a fluorescent contrast agent within a female breast, slightly compressed between two parallel glass plates, with high sensitivity. Fluorescence of the contrast agent is excited using a near infrared picosecond diode laser module. Four additional picosecond diode lasers with emission wavelengths between 660 and 1066 nm allow to measure the intrinsic optical properties of the breast tissue. By synchronously moving a source fiber and seven detection fiber bundles across the breast, distributions of times of flight of photons are recorded simultaneously for selected source-detector combinations in transmission and reflection geometry either at the fluorescence wavelength or at the selected laser wavelengths. To evaluate the performance of the mammograph, we used breastlike rectangular phantoms comprising fluorescent and absorbing objects using the fluorescent dye Omocyanine as contrast agent excited at 735 nm. We compare two-dimensional imaging of the phantom based on transmission and reflection data. Furthermore, we developed an improved tomosynthesis algorithm which permits three-dimensional reconstruction of fluorescence and absorption properties of lesions with good spatial resolution. For illustration, we present fluorescence mammograms of one patient recorded 30 min after administration of the contrast agent indocyanine green showing the carcinoma at high contrast originating from fluorescence of the extravasated dye, excited at 780 nm.
authors.affiliation: Physikalisch-Technische Bundesanstalt (PTB), Berlin, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Grosenick
authors.forename: Axel
authors.initials: A
authors.lastname: Hagen
authors.forename: Oliver
authors.initials: O
authors.lastname: Steinkellner
authors.forename: Alexander
authors.initials: A
authors.lastname: Poellinger
authors.forename: Susen
authors.initials: S
authors.lastname: Burock
authors.forename: Peter M
authors.initials: PM
authors.lastname: Schlag
authors.forename: Herbert
authors.initials: H
authors.lastname: Rinneberg
authors.forename: Rainer
authors.initials: R
authors.lastname: Macdonald
mesh_terms: D000465:Algorithms; D001943:Breast Neoplasms / Q000000981:diagnostic imaging; D005240:Feasibility Studies; D006801:Humans; D021621:Imaging, Three-Dimensional; D057230:Limit of Detection; D008327:Mammography / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D013997:Time Factors