Acoustic-speed correction of photoacoustic tomography by ultrasonic computed tomography based on optical excitation of elements of a full-ring transducer array

被引:1
|
作者
Xia, Jun [1 ]
Huang, Chao [1 ]
Maslov, Konstantin [1 ]
Anastasio, Mark A. [1 ]
Wang, Lihong V. [1 ]
机构
[1] Washington Univ, Dept Biomed Engn, St Louis, MO 63130 USA
来源
PHOTONS PLUS ULTRASOUND: IMAGING AND SENSING 2014 | 2014年 / 8943卷
关键词
Ultrasound computed tomography; photoacoustic computed tomography; image reconstruction; speed of sound;
D O I
10.1117/12.2036615
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
Photoacoustic computed tomography (PACT) is a hybrid technique that combines optical excitation and ultrasonic detection to provide high resolution images in deep tissues. In the image reconstruction, a constant speed of sound (SOS) is normally assumed. This assumption, however, is often not strictly satisfied in deep tissue imaging, due to acoustic heterogeneities within the object and between the object and coupling medium. If these heterogeneities are not accounted for, they will cause distortions and artifacts in the reconstructed images. In this paper, we incorporated ultrasonic computed tomography (USCT), which measures the SOS distribution within the object, into our full-ring array PACT system. Without the need for ultrasonic transmitting electronics, USCT was performed using the same laser beam as for PACT measurement. By scanning the laser beam on the array surface, we can sequentially fire different elements. As a first demonstration of the system, we studied the effect of acoustic heterogeneities on photoacoustic vascular imaging. We verified that constant SOS is a reasonable approximation when the SOS variation is small. When the variation is large, distortion will be observed in the periphery of the object, especially in the tangential direction.
引用
收藏
页数:6
相关论文
共 23 条