Photoacoustic imaging of mouse brain using ultrasonic transducers with different central frequencies

A circular scanning photoacoustic imaging system was utilized to image the blood vessels of a mouse brain. The ultrasonic transducers with central frequencies of 2.25 MHz and 5 MHz, respectively, were used. The photoacoustic signals as well as the recovered images of mouse brain were compared among the two different transducers. The results show that the vascular structure of the brain is imaged in higher resolution using the 5 MHz transducer, which implies that it is important to choose a transducer with proper central frequency for a particular biological tissue. This study demonstrates that photoacoustic imaging has the potential to become a new modality for functional brain imaging.