title: Temporal backward projection of optoacoustic pressure transients using fourier transform methods.
abstract: In medical imaging different techniques have been developed to gain information from inside a tissue. Optoacoustics is a method to generate tomography pictures of tissue using Q-switched laser pulses. Due to thermal and pressure confinement, a short light pulse generates a pressure distribution inside tissue, which mirrors absorbing structures and can be measured outside the tissue. Using a temporal back-projection method, the pressure distribution measured on the tissue surface allows us to gain a tomography picture of the absorbing structures inside tissue. This study presents a novel computational algorithm, which, at least in principle, yields an exact reconstruction of the absorbing structures in three-dimensional space inside the tissue. The reconstruction is based on 2D pressure distributions captured outside at different delay times. The algorithm is tested in a simulation and back-projection of pressure transients of a small absorber and a single point source.
authors.affiliation: Institute of Applied Physics, University of Bern, Switzerland.
authors.forename: K P
authors.initials: KP
authors.lastname: Köstli
authors.forename: M
authors.initials: M
authors.lastname: Frenz
authors.forename: H
authors.initials: H
authors.lastname: Bebie
authors.forename: H P
authors.initials: HP
authors.lastname: Weber
mesh_terms: D000162:Acoustics; D000465:Algorithms; D005583:Fourier Analysis; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008962:Models, Theoretical; D055095:Optics and Photonics; D011312:Pressure; D013223:Statistics as Topic; D013997:Time Factors