Optimal statistical approach to optoacoustic image reconstruction

An optimal statistical approach is applied to the task of image reconstruction in photoacoustics. The physical essence of the task is as follows: Pulse laser irradiation induces an ultrasound wave on the inhomogeneities inside the investigated volume. This acoustic wave is received by the set of receivers outside this volume. It is necessary to reconstruct a spatial image of these inhomogeneities. Developed mathematical techniques of the radio location theory are used for solving the task. An algorithm of maximum likelihood is synthesized for the image reconstruction. The obtained algorithm is investigated by digital modeling. The number of receivers and their disposition in space are arbitrary. Results of the synthesis are applied to noninvasive medical diagnostics (breast cancer). The capability of the algorithm is tested on real signals. The image is built with use of signals obtained in vitro. The essence of the algorithm includes (i) summing of all signals in the image plane with the transform from the time coordinates of signals to the spatial coordinates of the image and (ii) optimal spatial filtration of this sum. The results are shown in the figures. (C) 2000 Optical Society of America OCIS codes: 100.0100, 100.2980, 100.3020, 100.6950.