title: Validation of Ultrasound Elastography Imaging for Nondestructive Characterization of Stiffer Biomaterials.
abstract: Ultrasound elastography (UE) has been widely used as a "digital palpation" tool to characterize tissue mechanical properties in the clinic. UE benefits from the capability of noninvasively generating 2-D elasticity encoded maps. This spatial distribution of elasticity can be especially useful in the in vivo assessment of tissue engineering scaffolds and implantable drug delivery platforms. However, the detection limitations have not been fully characterized and thus its true potential has not been completely discovered. Characterization studies have focused primarily on the range of moduli corresponding to soft tissues, 20-600 kPa. However, polymeric biomaterials used in biomedical applications such as tissue scaffolds, stents, and implantable drug delivery devices can be much stiffer. In order to explore UE's potential to assess mechanical properties of biomaterials in a broader range of applications, this work investigated the detection limit of UE strain imaging beyond soft tissue range. To determine the detection limit, measurements using standard mechanical testing and UE on the same polydimethylsiloxane samples were compared and statistically evaluated. The broadest detection range found based on the current optimized setup is between 47 kPa and 4 MPa which exceeds the modulus of normal soft tissue suggesting the possibility of using this technique for stiffer materials' mechanical characterization. The detectable difference was found to be as low as 157 kPa depending on sample stiffness and experimental setup.
authors.affiliation: Department of Biomedical Engineering, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH, 44106-5056, USA.
authors.forename: Haoyan
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Department of Biomedical Engineering, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH, 44106-5056, USA.
authors.forename: Monika
authors.initials: M
authors.lastname: Goss
authors.affiliation: Department of Biomedical Engineering, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH, 44106-5056, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Hernandez
authors.affiliation: Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH, 44106-5056, USA.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Mansour
authors.affiliation: Department of Radiology, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH, 44106-5056, USA. Agata.exner@case.edu.
authors.forename: Agata
authors.initials: A
authors.lastname: Exner
mesh_terms: D004129:Dimethylpolysiloxanes; D054459:Elasticity Imaging Techniques / Q000295:instrumentation* / Q000379:methods*; D009757:Nylons; D019047:Phantoms, Imaging; D012826:Silicone Elastomers
chemical_list: D004129:Dimethylpolysiloxanes; D009757:Nylons; D012826:Silicone Elastomers; C085707:poly(dimethylsiloxane)-polyamide copolymer
keywords: Biomaterial characterization; Elasticity; Mechanical; Nondestructive; Noninvasive; Ultrasound elastography