Synthetic aperture photoacoustic imaging on small vessel phantom study

Photoacoustic imaging has been shown to have higher spatial resolution and optical contrast than conventional ultrasonic imaging. In this study, we investigate the photoacoustic imaging characteristic on small vessel phantoms of 1mm TYGON and 100 μ m microdialysis tubes. A 1064 nm Nd:YAG laser was used to excite the tubes, which were filled with hemoglobin and were immersed in tissue like scattering media. The photoacoustic images were obtained by using 3.5MHz and 20MHz transducers. We also used synthetic aperture technique to reconstruct photoacoustic image and improve the image contrast and resolution. This study demonstrates the improvement of photoacoustic image by synthetic aperture technique.