Assessment of Structural Heterogeneity and Viscosity in the Cervix Using Shear Wave Elasticity Imaging: Initial Results from a Rhesus Macaque Model.

Journal Article

Shear wave elasticity imaging has shown promise in evaluation of the pregnant cervix. Changes in shear wave group velocity have been attributed exclusively to changes in stiffness. This assumes homogeneity within the region of interest and purely elastic tissue behavior. However, the cervix is structurally/microstructurally heterogeneous and viscoelastic. We therefore developed strategies to investigate these complex tissue properties. Shear wave elasticity imaging was performed ex vivo on 14 unripened and 13 misoprostol-ripened cervix specimens from rhesus macaques. After tests of significant and uniform shear wave displacement, as well as reliability of estimates, group velocity decreased significantly from the distal (vaginal) to proximal (uterine) end of unripened, but not ripened, specimens. Viscosity was quantified by the slope of the phase velocity versus frequency. Dispersion was observed in both groups (median: 5.5 m/s/kHz, interquartile range: 1.5-12.0 m/s/kHz), also decreasing toward the proximal cervix. This work suggests that comprehensive assessment of complex tissues such as cervix requires consideration of structural heterogeneity and viscosity.

Full Text

Duke Authors

Cited Authors

  • Rosado-Mendez, IM; Palmeri, ML; Drehfal, LC; Guerrero, QW; Simmons, H; Feltovich, H; Hall, TJ

Published Date

  • April 2017

Published In

Volume / Issue

  • 43 / 4

Start / End Page

  • 790 - 803

PubMed ID

  • 28189282

Electronic International Standard Serial Number (EISSN)

  • 1879-291X

International Standard Serial Number (ISSN)

  • 0301-5629

Digital Object Identifier (DOI)

  • 10.1016/j.ultrasmedbio.2016.12.006

Language

  • eng