Ultrasound-heated photoacoustic flowmetry.

نویسندگان

  • Lidai Wang
  • Junjie Yao
  • Konstantin I Maslov
  • Wenxin Xing
  • Lihong V Wang
چکیده

We report the development of photoacoustic flowmetry assisted by high-intensity focused ultrasound (HIFU). This novel method employs HIFU to generate a heating impulse in the flow medium, followed by photoacoustic monitoring of the thermal decay process. Photoacoustic flowmetry in a continuous medium remains a challenge in the optical diffusive regime. Here, both the HIFU heating and photoacoustic detection can focus at depths beyond the optical diffusion limit (~1 mm in soft tissue). This method can be applied to a continuous medium, i.e., a medium without discrete scatterers or absorbers resolvable by photoacoustic imaging. Flow speeds up to 41 mm·s-1 have been experimentally measured in a blood phantom covered by 1.5-mm-thick tissue.

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عنوان ژورنال:
  • Journal of biomedical optics

دوره 18 11  شماره 

صفحات  -

تاریخ انتشار 2013