Viscoelastic Characterization of Phantoms for Ultrasound Elastography Created Using Low- and High-Viscosity Poly(vinyl Alcohol) with Ethylene Glycol As the Cryoprotectant

Overview

Journal ACS Omega

Publisher American Chemical Society

Specialty Chemistry

Date 2024 Feb 26

PMID 38405437

Authors

Sapna R Bisht

Bhanu Prasad Marri

Jayashree Karmakar

Karla P Mercado Shekhar

Affiliations

Soon will be listed here.

Abstract

Ultrasound elastography enables noninvasive characterization of the tissue mechanical properties. Phantoms are widely used in ultrasound elastography for developing, testing, and validating imaging techniques. Creating phantoms with a range of viscoelastic properties relevant to human organs and pathological conditions remains an active area of research. Poly(vinyl alcohol) (PVA) cryogel phantoms offer a long shelf life, robustness, and convenient handling and storage. The goal of this study was to develop tunable phantoms using PVA with a clinically relevant range of viscoelastic properties. We combined low- and high-viscosity PVA to tune the viscoelastic properties of the phantom. Further, phantoms were created with an ethylene glycol-based cryoprotectant to determine whether it reduces the variability in the viscoelastic properties. Scanning electron microscopy (SEM) was performed to evaluate the differences in microstructure between phantoms. The density, longitudinal sound speed, and acoustic attenuation spectra (5-20 MHz) of the phantoms were measured. The phantoms were characterized using a shear wave viscoelastography approach assuming the Kelvin-Voigt model. Microstructural differences were revealed by SEM between phantoms with and without a cryoprotectant and with different PVA mixtures. The longitudinal sound speed and attenuation power-law fit exponent of the phantoms were within the clinical range (1510-1571 m/s and 1.23-1.38, respectively). The measured shear modulus () ranged from 3.3 to 17.7 kPa, and the viscosity (η) ranged from 2.6 to 7.3 Pa·s. The phantoms with the cryoprotectant were more homogeneous and had lower shear modulus and viscosity ( = 2.17 ± 0.2 kPa; η = 2.0 ± 0.05 Pa·s) than those without a cryoprotectant ( = 3.93 ± 0.7 kPa; η = 2.6 ± 0.14 Pa·s). Notably, phantoms with relatively constant viscosities and varying shear moduli were achieved by this method. These findings advance the development of well-characterized viscoelastic phantoms for use in elastography.

References

Lim W, Ooi E, Foo J, Ng K, Wong J, Leong S . The role of shear viscosity as a biomarker for improving chronic kidney disease detection using shear wave elastography: A computational study using a validated finite element model. Ultrasonics. 2023; 133:107046. DOI: 10.1016/j.ultras.2023.107046. View

Surry K, Austin H, Fenster A, Peters T . Poly(vinyl alcohol) cryogel phantoms for use in ultrasound and MR imaging. Phys Med Biol. 2005; 49(24):5529-46. DOI: 10.1088/0031-9155/49/24/009. View

Wang T, Chen L, Shen T, Wu D . Preparation and properties of a novel thermo-sensitive hydrogel based on chitosan/hydroxypropyl methylcellulose/glycerol. Int J Biol Macromol. 2016; 93(Pt A):775-782. DOI: 10.1016/j.ijbiomac.2016.09.038. View

Palmeri M, Wang M, Dahl J, Frinkley K, Nightingale K . Quantifying hepatic shear modulus in vivo using acoustic radiation force. Ultrasound Med Biol. 2008; 34(4):546-58. PMC: 2362504. DOI: 10.1016/j.ultrasmedbio.2007.10.009. View

Parker K, Szabo T, Holm S . Towards a consensus on rheological models for elastography in soft tissues. Phys Med Biol. 2019; 64(21):215012. PMC: 8042759. DOI: 10.1088/1361-6560/ab453d. View

Dulgheriu I, Solomon C, Muntean D, Petea-Balea R, Lenghel M, Ciurea A . Shear-Wave Elastography and Viscosity PLUS for the Assessment of Peripheric Muscles in Healthy Subjects: A Pre- and Post-Contraction Study. Diagnostics (Basel). 2022; 12(9). PMC: 9497738. DOI: 10.3390/diagnostics12092138. View

Poul S, Ormachea J, Ge G, Parker K . Comprehensive experimental assessments of rheological models' performance in elastography of soft tissues. Acta Biomater. 2022; 146:259-273. PMC: 9335515. DOI: 10.1016/j.actbio.2022.04.047. View

Raymond J, Haworth K, Bader K, Radhakrishnan K, Griffin J, Huang S . Broadband attenuation measurements of phospholipid-shelled ultrasound contrast agents. Ultrasound Med Biol. 2013; 40(2):410-21. PMC: 4026002. DOI: 10.1016/j.ultrasmedbio.2013.09.018. View

Palmeri M, Milkowski A, Barr R, Carson P, Couade M, Chen J . Radiological Society of North America/Quantitative Imaging Biomarker Alliance Shear Wave Speed Bias Quantification in Elastic and Viscoelastic Phantoms. J Ultrasound Med. 2021; 40(3):569-581. PMC: 8082942. DOI: 10.1002/jum.15609. View

10.

Shekhar H, Smith N, Raymond J, Holland C . Effect of Temperature on the Size Distribution, Shell Properties, and Stability of Definity. Ultrasound Med Biol. 2017; 44(2):434-446. PMC: 5759968. DOI: 10.1016/j.ultrasmedbio.2017.09.021. View

11.

Kumar V, Denis M, Gregory A, Bayat M, Mehrmohammadi M, Fazzio R . Viscoelastic parameters as discriminators of breast masses: Initial human study results. PLoS One. 2018; 13(10):e0205717. PMC: 6185851. DOI: 10.1371/journal.pone.0205717. View

12.

Prokop A, Vaezy S, Noble M, Kaczkowski P, Martin R, Crum L . Polyacrylamide gel as an acoustic coupling medium for focused ultrasound therapy. Ultrasound Med Biol. 2003; 29(9):1351-8. DOI: 10.1016/s0301-5629(03)00979-7. View

13.

Bots M, Evans G, Riley W, Grobbee D . Carotid intima-media thickness measurements in intervention studies: design options, progression rates, and sample size considerations: a point of view. Stroke. 2003; 34(12):2985-94. DOI: 10.1161/01.STR.0000102044.27905.B5. View

14.

Culjat M, Goldenberg D, Tewari P, Singh R . A review of tissue substitutes for ultrasound imaging. Ultrasound Med Biol. 2010; 36(6):861-73. DOI: 10.1016/j.ultrasmedbio.2010.02.012. View

15.

Chen S, Urban M, Pislaru C, Kinnick R, Zheng Y, Yao A . Shearwave dispersion ultrasound vibrometry (SDUV) for measuring tissue elasticity and viscosity. IEEE Trans Ultrason Ferroelectr Freq Control. 2009; 56(1):55-62. PMC: 2658640. DOI: 10.1109/TUFFC.2009.1005. View

16.

Madsen E, Hobson M, Shi H, Varghese T, Frank G . Tissue-mimicking agar/gelatin materials for use in heterogeneous elastography phantoms. Phys Med Biol. 2005; 50(23):5597-618. PMC: 3769983. DOI: 10.1088/0031-9155/50/23/013. View

17.

Hollender P, Rosenzweig S, Nightingale K, Trahey G . Single- and multiple-track-location shear wave and acoustic radiation force impulse imaging: matched comparison of contrast, contrast-to-noise ratio and resolution. Ultrasound Med Biol. 2015; 41(4):1043-57. PMC: 4346467. DOI: 10.1016/j.ultrasmedbio.2014.11.006. View

18.

Cafarelli A, Verbeni A, Poliziani A, Dario P, Menciassi A, Ricotti L . Tuning acoustic and mechanical properties of materials for ultrasound phantoms and smart substrates for cell cultures. Acta Biomater. 2016; 49:368-378. DOI: 10.1016/j.actbio.2016.11.049. View

19.

Xue R, Xin X, Wang L, Shen J, Ji F, Li W . A systematic study of the effect of molecular weights of polyvinyl alcohol on polyvinyl alcohol-graphene oxide composite hydrogels. Phys Chem Chem Phys. 2015; 17(7):5431-40. DOI: 10.1039/c4cp05766j. View

20.

Fromageau J, Brusseau E, Vray D, Gimenez G, Delachartre P . Characterization of PVA cryogel for intravascular ultrasound elasticity imaging. IEEE Trans Ultrason Ferroelectr Freq Control. 2003; 50(10):1318-24. DOI: 10.1109/tuffc.2003.1244748. View