Bubble-enhanced heating during focused ultrasound surgery - Dr Bjoern Gerold

Published: 9 March 2017

Date & Time: Thursday 9th March, 14:00-15:00 Venue: Room 526, James Watt South Building

We are going to have a seminar on 'Bubble-enhanced heating during focused ultrasound surgery' on Thursday 9th March, 14:00-15:00, given by Dr Bjoern Gerold, R&D Engineer, Theraclion.

Abstract and biography are given below.

Date & Time:  Thursday 9th March, 14:00-15:00
Venue:           Room 526, James Watt South Building


Abstract

Acoustic cavitation is the formation of microscopic bubbles in a media exposed to high intensity focused ultrasound (HIFU). Cavitation is investigated in the context of therapeutic ultrasound in order to increase efficiency of ultrasonic thermal ablation. HIFU uses tightly focused acoustic beams to deliver the energy in the target leading to very high acoustic pressures in the focal area. Bubbles that form during negative pressure phases could enhance energy deposition due to viscous effects and scattering. Unfortunately the unpredictable nature of cavitation can result in irregular spatial distribution of the thermal absorption. Therefore cavitation in medicine is still considered a dangerous side effect, and is generally avoided. With better understanding of cavitation dynamics, more sensitive detectors and faster electronics it is possible to closely monitor cavitation activity via its acoustic emissions and take advantage of its potential.
 

The talk will be focused on the development of an instrument capable to control acoustic cavitation at sub-millisecond speed. The system has been tested in tissue phantom, ex-vivo tissue and in-vivo tissue. The cavitation noise signal has been recorded and processed by a field programmable-gated array coupled with a feedback loop capable to control the driving field accordingly. The driving field emitted by a 1MHz focused ultrasound transducer can be modulated every few hundreds of microseconds to maintain an ideal level of cavitation activity for energy absorption at the focus.

“The research leading to these results has received funding from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007-2013/under REA grant agreement n° [623608].”

Biography

Currently, as a Marie Curie Research Fellow I am hosted at Theraclion SA for a 2 year funded European project. The objective of the CavAblate project is to implement new cavitation characterization detection and control techniques that can be applied in Focused Ultrasound Surgery. I have gained my BSc and MSc degree in biomedical engineering at the University of Padova, Italy. The BSc with a thesis in software based research and the masters with a thesis in ultrasound device hardware design. I obtained a PhD in physics from the University of Dundee, with the Thesis entitled ‘Cavitation in focused ultrasound’. In Dundee I was based in the Institute of Medical Science for Technology and I was a Marie Curie Fellow in the European funded Nanoporation project, which investigated local drug delivery for cancer treatments. This project allowed me to be seconded for an extended time to InSightec, world leading in MRI guided focused ultrasound surgery.

First published: 9 March 2017