title: Bubble dynamics and size distributions during focused ultrasound insonation.
abstract: The deposition of ultrasonic energy in tissue can cause tissue damage due to local heating. For pressures above a critical threshold, cavitation will occur, inducing a much larger thermal energy deposition in a local region. The present work develops a nonlinear bubble dynamics model to numerically investigate bubble oscillations and bubble-enhanced heating during focused ultrasound (HIFU) insonation. The model is applied to calculate two threshold-dependent phenomena occurring for nonlinearly oscillating bubbles: Shape instability and growth by rectified diffusion. These instabilities in turn are shown to place physical boundaries on the time-dependent bubble size distribution, and thus the thermal energy deposition.
authors.affiliation: National Center for Physical Acoustics, University of Mississippi, 1 Coliseum Drive, University, Mississippi 38677, USA. xmyang@olemiss.edu
authors.forename: Xinmai
authors.initials: X
authors.lastname: Yang
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Roy
authors.forename: R Glynn
authors.initials: RG
authors.lastname: Holt
mesh_terms: D001696:Biomechanical Phenomena; D005740:Gases / Q000009:adverse effects*; D006361:Heating / Q000009:adverse effects* / Q000295:instrumentation; D006801:Humans; D045423:Microbubbles / Q000009:adverse effects*; D008962:Models, Theoretical; D017711:Nonlinear Dynamics; D019047:Phantoms, Imaging; D017695:Soft Tissue Injuries / Q000209:etiology*; D013816:Thermodynamics; D014464:Ultrasonic Therapy / Q000009:adverse effects* / Q000295:instrumentation; D014783:Viscosity
chemical_list: D005740:Gases