SEMINAR: Quantitative ultrasound techniques for monitoring cervical remodeling in pregnancy
April 20 @ 10:00 am - 11:00 am
The cervix is a remarkable organ. One of its tasks is to remain firm and “closed” (5 mm diameter cervical canal) prior to pregnancy. Shortly after conception the cervix begins to soften through collagen remodeling and increased hydration. As the fetus reaches full-term there is a profound breakdown in the collagen structure. At the end of this process, the cervix is as soft as warm butter and the cervical canal has dilated to about 100 mm diameter. Errors in timing of this process are a cause for preterm birth, which has a cascade of life-threatening consequences. Quantitative ultrasound is well-suited to monitoring these changes. We have demonstrated the ability to accurately assess the elastic properties and acoustic scattering properties (anisotropy in backscatter and attenuation) of the cervix in non-pregnant hysterectomy specimens and in third trimester pregnancy. We’ve shown that acoustic and mechanical properties vary along the length of the cervix. When anisotropy and spatially variability are accounted for, there are clear differences in parameter values with subtle differences in softening. We are corroborating acoustic observations with nonlinear optical microscopy imaging for a reality check on underlying tissue structure. This presentation will provide an overview of this effort.
Timothy Hall is a Professor of Medical Physics at the University of Wisconsin-Madison where he leads the Quantitative Ultrasound Lab and the Phantom Development Lab. He has contributed to algorithm development for several quantitative ultrasound parameters (e.g., backscatter coefficients, attenuation coefficients, tissue elasticity characterization, and parameters derived from them), development of image formation strategies, estimates of fundamental noise properties of parametric images, led the effort for system integration and initial clinical trials. His group collaborates with clinicians around the country, basic and applied scientists around the world, and provides a core resource to the international ultrasound community (commercial and academic) for test objects and their fundamental characterization.