Optical absorbance measurements and photoacoustic evaluation of freeze-thawed polyvinyl-alcohol vessel phantoms

M. U. Arabul, H. M. Heres, M. Rutten, F. Van De Vosse, R. Lopata

Research output: Chapter in Book/Report/Conference proceedingConference contributionAcademicpeer-review

1 Citation (Scopus)
4 Downloads (Pure)

Abstract

Multispectral photoacoustic (MPA) imaging is a promising tool for the diagnosis of atherosclerotic carotids. Excitation of different constituents of a plaque with different wavelengths of the light may provide morphological information to evaluate plaque vulnerability. Preclinical validation of in vivo photoacoustic (PA) imaging requires a comprehensive phantom study. In this study, the design of optically realistic vessel phantoms for photoacoustics was examined by characterizing their optical properties for different dye concentrations, and comparing those to PA measurements. Four different concentrations of Indian ink and molecular dye were added to a 15 wt% PVA and 1 wt% orgasol mixture. Next, the homogeneously mixed gels were subjected to five freeze - thaw cycles to increase the stiffness of vessel phantoms (rinner = 2.5mm, router = 4mm). For each cycle, the optical absorbance was measured between 400 nm 990 nm using a plate reader. Additionally, photoacoustic responses of each vessel phantom at 808 nm were tested with a novel, hand-held, integrated PA probe. Measurements show that the PA signal intensity increases with the optical absorber concentration (0.3 to 0.9) in close agreement with the absorbance measurements. The freeze - thaw process has no significant effect on PA intensity. However, the total attenuation of optical energy increases after each freeze-thaw cycle, which is primarily due to the increase in the scattering coefficient. In future work, the complexity of these phantoms will be increased to examine the feasibility of distinguishing different constituents with MPA imaging.

Original languageEnglish
Title of host publicationProgress in Biomedical Optics and Imaging
PublisherSPIE
Number of pages5
ISBN (Print)9781628414134
DOIs
Publication statusPublished - 2015
EventPhotons Plus Ultrasound: Imaging and Sensing 2015 - San Francisco, United States
Duration: 8 Feb 201510 Feb 2015

Publication series

NameProceedings of SPIE
Volume9323

Conference

ConferencePhotons Plus Ultrasound: Imaging and Sensing 2015
CountryUnited States
CitySan Francisco
Period8/02/1510/02/15

Keywords

  • Atherosclerosis
  • Carotid
  • Hand-held probe
  • Optical characterization
  • Phantoms
  • Photoacoustics
  • Polyvinyl alcohol

Fingerprint Dive into the research topics of 'Optical absorbance measurements and photoacoustic evaluation of freeze-thawed polyvinyl-alcohol vessel phantoms'. Together they form a unique fingerprint.

Cite this