title: Estimation of mechanical properties of a viscoelastic medium using a laser-induced microbubble interrogated by an acoustic radiation force.
abstract: An approach to assess the mechanical properties of a viscoelastic medium using laser-induced microbubbles is presented. To measure mechanical properties of the medium, dynamics of a laser-induced cavitation microbubble in viscoelastic medium under acoustic radiation force was investigated. An objective lens with a 1.13 numerical aperture and an 8.0 mm working distance was designed to focus a 532 nm wavelength nanosecond pulsed laser beam and to create a microbubble at the desired location. A 3.5 MHz ultrasound transducer was used to generate acoustic radiation force to excite a laser-induced microbubble. Motion of the microbubble was tracked using a 25 MHz imaging transducer. Agreement between a theoretical model of bubble motion in a viscoelastic medium and experimental measurements was demonstrated. Young's modulii reconstructed using the laser-induced microbubble approach were compared with those measured using a direct uniaxial method over the range from 0.8 to 13 kPa. The results indicate good agreement between methods. Thus, the proposed approach can be used to assess the mechanical properties of a viscoelastic medium.
authors.affiliation: Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712-1063, USA.
authors.forename: Sangpil
authors.initials: S
authors.lastname: Yoon
authors.forename: Salavat R
authors.initials: SR
authors.lastname: Aglyamov
authors.forename: Andrei B
authors.initials: AB
authors.lastname: Karpiouk
authors.forename: Seungsoo
authors.initials: S
authors.lastname: Kim
authors.forename: Stanislav Y
authors.initials: SY
authors.lastname: Emelianov
mesh_terms: D000162:Acoustics / Q000295:instrumentation*; D000818:Animals; D001696:Biomechanical Phenomena; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000295:instrumentation*; D006801:Humans; D053844:Lasers, Solid-State; D007908:Lens, Crystalline / Q000502:physiology*; D045423:Microbubbles; D008962:Models, Theoretical; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D013552:Swine; D014159:Transducers; D014783:Viscosity