Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Development of Ultrasound Pulse Sequences for Acoustic Droplet Vaporization
KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
2019 (English)Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesisAlternative title
Utveckling av ultraljudspulssekvenser för akustisk vaporisering av vätskedroppar (Swedish)
Abstract [en]

Ultrasound-mediated drug delivery has been proposed as a safe and non-invasive method to achieve localized drug release. Drug-loaded microbubbles are injected in the vascular system and ultrasound waves are then used to localize and burst the microbubbles at a specific targeted area. The relatively large size of microbubbles however limits both their lifetime and their reach in the human body.

Phase-change liquid droplets can extend the use of ultrasound contrast agents for localized drug delivery. Their smaller size provides several advantages. The droplets can reach smaller capillaries, such as those in tumors vasculature. Their lifetime is also considerably prolonged.

Through the phenomenon of Acoustic Droplet Vaporization (ADV), triggered by ultrasound stimulation, the liquid-filled droplets experience a phase change and are converted into gas-filled microbubbles. The newly created microbubbles can then be disrupted by further stimulation and release their drug load in the tumor tissue.

In this project, a protocol to image and burst perfluoropentane-based micro-sized droplets using a single transducer is developed using the Verasonics Ultrasound System.

The pulse sequences are developed to allow close monitoring of the drug delivery by capturing a series of images before and after the vaporization or destruction of the droplets.

The droplets response was assessed for different pulse voltages and durations. Mean pixel value was calculated for the regions of interest, using the images captured before and after delivery of the ultrasound pulse.

Vaporization of the droplets can be achieved with low voltage (10V), whereas high voltage (50V) triggers their destruction.

Combined with high voltage, pulse duration affects the rate at which droplets can be destructed.

Place, publisher, year, edition, pages
2019. , p. 39
Series
TRITA-CBH-GRU ; 2019:084
Keywords [en]
Ultrasound, Ultrasound contrast agents, Phase-change contrast agents, Acoustic droplet vaporization, Verasonics
National Category
Medical Engineering
Identifiers
URN: urn:nbn:se:kth:diva-253358OAI: oai:DiVA.org:kth-253358DiVA, id: diva2:1325197
Educational program
Master of Science in Engineering - Medical Engineering
Presentation
2019-06-04, 17:45 (English)
Supervisors
Examiners
Available from: 2019-06-20 Created: 2019-06-14 Last updated: 2019-06-20Bibliographically approved

Open Access in DiVA

fulltext(1914 kB)30 downloads
File information
File name FULLTEXT01.pdfFile size 1914 kBChecksum SHA-512
8c4b24f035397fcab98c618cc9b29b5079cf4f17789aada3674acae4d206018197f7cca501890b0c85f42e492b15cf6aa3f3081ce2707aec012f809064a01484
Type fulltextMimetype application/pdf

By organisation
School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH)
Medical Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 30 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 153 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf