Realtime photoacoustic microscopy in vivo with a 30-MHz ultrasound array transducer.
We present a novel high-frequency photoacoustic microscopy system capable of imaging the microvasculature of living subjects in realtime to depths of a few mm. The system consists of a high-repetition-rate Q-switched pump laser, a tunable dye laser, a 30-MHz linear ultrasound array transducer, a multichannel high-frequency data acquisition system, and a shared-RAM multi-core-processor computer. Data acquisition, beamforming, scan conversion, and display are implemented in realtime at 50 frames per second. Clearly resolvable images of 6-microm-diameter carbon fibers are experimentally demonstrated at 80 microm separation distances. Realtime imaging performance is demonstrated on phantoms and in vivo with absorbing structures identified to depths of 2.5-3 mm. This work represents the first high-frequency realtime photoacoustic imaging system to our knowledge.
Washington University, Optical Imaging Laboratory, Department of Biomedical Engineering, Saint Louis, Missouri 63130, USA.
Roger J
RJ
Zemp
Liang
L
Song
Rachel
R
Bitton
K Kirk
KK
Shung
Lihong V
LV
Wang
D003198:Computer Simulation; D003199:Computer Systems; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D008833:Microcirculation / Q000000981:diagnostic imaging*; D033401:Microscopy, Acoustic / Q000295:instrumentation* / Q000379:methods; D008962:Models, Theoretical; D019047:Phantoms, Imaging; D011846:Radio Waves; D014159:Transducers