The Physical Effects of Bubbles and Cavitation in High Intensity ...

More documents

Recommendations

Info

Presentation Abstract The application of ultrasound to tissue at therapeutic levels can, in some cases, result in bubble formation. These bubbles can promote mechanical disruption, accelerate tissue heating, and contribute to the formation of irregularly shaped lesions. The relevant mechanical and thermal effects depend critically on several factors, such as temporal peak and temporal average acoustic intensity, the duration of cw insonation, the duration and duty cycle of pulse insonation, the presence of cavitation nuclei, tissue temperature, and the tissue acoustic, rheological, and thermal properties. We will present a brief primer on the relevant bubble dynamics followed by a summary description of what physical effects matter, when and why. Implications for HIFU treatment monitoring through the active and passive bubble detection are discussed. [Work supported by the Dept. of the Army (award No. DAMD17-02-2-0014) and the Center for Subsurface Sensing and Imaging Systems (NSF ERC Award No. EEC-9986821).] 2
Medical Ultrasonics in a Nutshell Diagnostic Procedures Imaging, blood flow, multi-mode, molecular, functional Therapeutic Procedures Tissue healing/destruction Hemostasis & thrombolysis Drug delivery and much more Process Control Mixing, cleaning, lysis, sonoporation, sonochemistry Thermal & Mechanical Effects 3
Page 1: The Physical Effects of Bubbles and
Page 5 and 6: A Prominent Role for Microbubbles!
Page 7 and 8: Acoustic Cavitation A Recipe… Sta
Page 9 and 10: Physical Effects Stable Cavitation
Page 11 and 12: Physical Effects Inertial Cavitatio
Page 13 and 14: Physical Effects Inertial Cavitatio
Page 15 and 16: Physical Effects Collapse Jets Extr
Page 17 and 18: Geneology of Cavitation Cloud Colla
Page 19 and 20: Focused Ultrasound Surgery Tissue H
Page 21 and 22: Focused Ultrasound Surgery Tissue H
Page 23 and 24: Focused Ultrasound Surgery Dependen
Page 25 and 26: Sensing Accelerated Heating with No
Page 27 and 28: Can We Control -- or at least monit
Page 29 and 30: A Simple Cavitation Controller? 10
Page 31 and 32: What Happens if the Tissue Gets Too
Page 33 and 34: Not Necessarily So long as you
Page 35: I Thank… YOU, FOR YOUR KIND ATTEN

The Physical Effects of Bubbles and Cavitation in High Intensity ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?