hotoacoustic tomography of small animal brain with a urved array transducer

ihong V. Wang ashington University in St. Louis epartment of Biomedical Engineering ptical Imaging Laboratory t. Louis, Missouri 63130 Abstract. We present the application of a curved array photoacoustic tomographic imaging system that can provide rapid, high-resolution photoacoustic imaging of small animal brains. The system is optimized to produce a B-mode, 90-deg field-of-view image at sub-200m resolution at a frame rate of 1 frame/second when a 10-Hz pulse repetition rate laser is employed. By rotating samples, a complete 360-deg scan can be achieved within 15 s. In previous work, two-dimensional 2-D ex vivo mouse brain cortex imaging has been reported. We report three-dimensional 3-D small animal brain imaging obtained with the curved array system. The results are presented as a series of 2-D cross-sectional images. Besides structural imaging, the blood oxygen saturation of the animal brain cortex is also measured in vivo. In addition, the system can measure the timeresolved relative changes in blood oxygen saturation level in the small animal brain cortex. Last, ultrasonic gel coupling, instead of the previously adopted water coupling, is conveniently used in near-realtime 2-D imaging. © 2009 Society of Photo-Optical Instrumentation Engineers. DOI: 10.1117/1.3227035