Open AccessEnhancement of photoacoustic image quality by sound speed correction: ex vivo evaluation
Author(s) -
Changhan Yoon,
Jeeun Kang,
SeoJung Han,
Yangmo Yoo,
Tai-Kyong Song,
Jin Ho Chang
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.003082
Subject(s) - speed of sound , image quality , acoustics , beamforming , photoacoustic imaging in biomedicine , image resolution , computer science , optics , signal (programming language) , microcalcification , sound (geography) , materials science , image (mathematics) , computer vision , physics , mammography , telecommunications , medicine , cancer , breast cancer , programming language
Real-time photoacoustic (PA) imaging involves beamforming methods using an assumed fixed sound speed, typically 1540 m/s in soft tissue. This leads to degradation of PA image quality because the true sound speed changes as PA signal propagates through different types of soft tissues: the range from 1450 m/s to 1600 m/s. This paper proposes a new method for estimating an optimal sound speed to enhance the cross-sectional PA image quality. The optimal sound speed is determined when coherent factor with the sound speed is maximized. The proposed method was validated through simulation and ex vivo experiments with microcalcification-contained breast cancer specimen. The experimental results demonstrated that the best lateral resolution of PA images of microcalcifications can be achieved when the optimal sound speed is utilized.