Photo-acoustic excitation and optical detection of fundamental flexural guided wave in coated bone phantoms

Petro Moilanen; Zuomin Zhao; Pasi Karppinen; Timo Karppinen; Vantte Kilappa; Jalmari Pirhonen; Risto Myllylä; Edward Haeggström; Jussi Timonen

doi:10.1016/j.ultrasmedbio.2013.10.018

Photo-acoustic excitation and optical detection of fundamental flexural guided wave in coated bone phantoms

Ultrasound Med Biol. 2014 Mar;40(3):521-31. doi: 10.1016/j.ultrasmedbio.2013.10.018. Epub 2013 Dec 19.

Authors

Petro Moilanen¹, Zuomin Zhao², Pasi Karppinen³, Timo Karppinen³, Vantte Kilappa⁴, Jalmari Pirhonen⁴, Risto Myllylä⁵, Edward Haeggström³, Jussi Timonen⁴

Affiliations

¹ Department of Physics, University of Jyväskylä, Jyväskylä, Finland. Electronic address: petro.moilanen@jyu.fi.
² Department of Physics, University of Jyväskylä, Jyväskylä, Finland; Department of Electrical Engineering, University of Oulu, Oulu, Finland.
³ Department of Physics, University of Helsinki, Helsinki, Finland.
⁴ Department of Physics, University of Jyväskylä, Jyväskylä, Finland.
⁵ Department of Electrical Engineering, University of Oulu, Oulu, Finland.

PMID: 24361218
DOI: 10.1016/j.ultrasmedbio.2013.10.018

Abstract

Photo-acoustic (PA) imaging was combined with skeletal quantitative ultrasound (QUS) for assessment of human long bones. This approach permitted low-frequency excitation and detection of ultrasound so as to efficiently receive the thickness-sensitive fundamental flexural guided wave (FFGW) through a coating of soft tissue. The method was tested on seven axisymmetric bone phantoms, whose 1- to 5-mm wall thickness and 16-mm diameter mimicked those of the human radius. Phantoms were made of a composite material and coated with a 2.5- to 7.5-mm layer of soft material that mimicked soft tissue. Ultrasound was excited with a pulsed Nd:YAG laser at 1064-nm wavelength and received on the same side of the coated phantom with a heterodyne interferometer. The FFGW was detected at 30-kHz frequency. Fitting the FFGW phase velocity by the FLC(1,1) tube mode provided an accurate (9.5 ± 4.0%) wall thickness estimate. Ultrasonic in vivo characterization of cortical bone thickness may thus become possible.

Keywords: Axial transmission; Cortical bone; Guided waves; Osteoporosis; Photo-acoustics; Quantitative ultrasound.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Acoustic Stimulation / instrumentation
Bone Density / physiology
Bone and Bones / diagnostic imaging*
Bone and Bones / physiology*
Bone and Bones / radiation effects
Coated Materials, Biocompatible / chemical synthesis*
Densitometry / instrumentation*
Densitometry / methods
Elasticity Imaging Techniques / instrumentation*
Elasticity Imaging Techniques / methods
Equipment Design
Equipment Failure Analysis
Humans
Lasers*
Phantoms, Imaging*
Photic Stimulation / instrumentation
Reproducibility of Results
Sensitivity and Specificity
Sound

Substances

Coated Materials, Biocompatible