title: Analysis and modeling of an ultrasound-modulated guide star to increase the depth of focusing in a turbid medium.
abstract: The effects of strong scattering in tissue limit the depth to which light may be focused. However, it has been shown that scattering may be reduced utilizing adaptive optics with a focused ultrasound (US) beam guidestar. The optical signal traveling through the US beam waist is frequency shifted and may be isolated with demodulation. This paper utilizes a multiphysics simulation to model the optical and US interactions in both synthetic tissue and random scattering media. The results illustrate that optical energy may be focused within a turbid medium utilizing a US guidestar. The results also suggest that optical energy travels preferentially along optical channels within a turbid medium.
authors: Northeastern University, Department of Electrical and Computer Engineering, 409 Dana Research Center, 360 Huntington Avenue, Boston, MA 02115, USA. joe1h@aol.com
authors: Joseph L
authors: JL
authors: Hollmann
authors: Roarke
authors: R
authors: Horstmeyer
authors: Changhuei
authors: C
authors: Yang
authors: Charles A
authors: CA
authors: DiMarzio
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D008954:Models, Biological; D009391:Nephelometry and Turbidimetry; D061848:Optical Imaging / Q000379:methods* / Q000706:statistics & numerical data; D055620:Optical Phenomena; D019047:Phantoms, Imaging; D012542:Scattering, Radiation; D012867:Skin / Q000033:anatomy & histology; D014025:Titanium; D014465:Ultrasonics
chemical_list: C009495:titanium dioxide; D014025:Titanium