Please use this identifier to cite or link to this item:
Title: In vitro and in vivo evaluation of a magnetic resonance imaging-guided focused ultrasound system for dissolving clots in combination with thrombolytic drugs
Authors: Damianou, Christakis A. 
Hadjisavvas, Venediktos 
Ioannides, Kleanthis 
Keywords: MRI;Robot;Stroke;Thrombolysis
Category: Medical Engineering
Field: Engineering and Technology
Issue Date: 1-Jan-2014
Publisher: W.B. Saunders
Source: Journal of Stroke and Cerebrovascular Diseases Volume 23, Issue 7, August 2014, Pages 1956-1964
Abstract: Background The potential of a magnetic resonance imaging (MRI)-guided focused ultrasound (MRgFUS) system combined with thrombolytic drugs to dissolve clots is investigated using in vitro and in vivo models. Methods Two spherically focused transducers of 5 cm diameter focusing at 10 cm and operating at either.5 or 1 MHz were used. Doppler ultrasound was used to measure the blood flow during the in vivo experiments. Results The effect of ultrasound intensity, transducer beam area, and frequency on the dissolved volume was investigated. The goal was to maintain a temperature increase of less than 1°C (called safe temperature) at the clot during the application of pulsed ultrasound and at the same time achieve efficient thrombolysis. Conclusions The MRgFUS technique was proven successful in dissolving clots in vitro and in vivo. It was found that the volume of dissolved clot increases with acoustic intensity and beam size and decreases with frequency. With this system, it was possible to push ultrasound through a plastic phantom skull using a.5 MHz transducer. The beam of ultrasound through the phantom skull was monitored using the MRI technique of fast spoiled gradient. Finally, the thrombus in the in vivo model (ear artery) was successfully destroyed with the therapeutic protocols investigated in the in vitro models. This study shows that FUS using a single element MR-compatible transducer has the potential to treat clots in synergy with thrombolytic drugs. More advanced MRgFUS systems, such as phased arrays, will have a greater impact in sonothrombolysis.
ISSN: 10523057
Rights: © 2014 by National Stroke Association.
Type: Article
Appears in Collections:Άρθρα/Articles

Show full item record

Page view(s) 50

Last Week
Last month
checked on Nov 20, 2018

Google ScholarTM


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.