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Published on: August 16, 2012
Estimation method for sound velocity distribution for high-resolution ultrasonic tomographic imaging
Keiichiro Abe1, Mototaka Arakawa2,3, Hiroshi Kanai2,3
1Graduate School of Engineering, Tohoku University, Sendai, 980-8579, Japan. abekei@ecei.tohoku.ac.jp.
Purpose:
With commercial ultrasonic equipment, the sound velocity is fixed to a constant value of 1530 or 1540 m/s, which is used for beam formation. However, the assumption of a constant sound velocity is not optimal, as the sound velocity in a living body is heterogeneous. In this study, a novel method was proposed to estimate the distribution of the sound velocity in a region of interest.
Methods:
The sound velocity distribution was estimated by fitting the theoretical propagation time of the ultrasonic wave from the scatterer to each of the probe elements with measured values.
Results:
In a phantom experiment, the sound velocity distribution was estimated by the proposed method with a maximum estimation error of 0.6%, and the resultant local sound velocity values successfully improved the quality of the ultrasonic image.
Conclusion:
The proposed method has the potential to improve ultrasonic image quality in in vivo experiments by estimating the sound velocity distribution.
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