TITLE:
Cervical Characterization with Tactile-Ultrasound Probe
AUTHORS:
Vladimir Egorov, Todd Rosen, Heather van Raalte, Viktors Kurtenoks
KEYWORDS:
Cervical Elasticity, Cervical Length, Tactile, Ultrasound, Elastography, Premature Cervical Softening, Spontaneous Preterm Delivery
JOURNAL NAME:
Open Journal of Obstetrics and Gynecology,
Vol.10 No.1,
January
8,
2020
ABSTRACT: Background: Premature cervical softening and shortening may be considered an early
mechanical failure that predisposes to preterm birth. Preliminary clinical
studies demonstrate that cervical elastography may be able to quantify this
phenomenon and predict spontaneous preterm delivery. Objective: To
explore a new approach for cervix elasticity and length measurements with
tactile-ultrasound probe. Methods: Cervix probe has tactile array and
ultrasound transducer designed to apply controllable load to cervix and acquire
stress-strain data for calculation of cervical elasticity (Young’s modulus) and cervical length for four cervix sectors.
Average values, standard deviations, intraclass correlation coefficients and
the 95% limits of agreement (Bland-Altman plots) were estimated. Results: Ten non-pregnant and ten pregnant women were examined with the probe. The study with non-pregnant
women demonstrated a reliable acquisition of the tactile signals. The
ultrasound signals had a prolonged appearance; identification of the internal
os of the cervix in these signals was not reliable. The study with pregnant
women with the gestational age of 25.4 ± 2.3
weeks demonstrated reliable data acquisition with real-time visualization of
the ultrasound signals. Average values for cervical elasticity and standard
deviations of 19.7 ± 15.4 kPa and length of 30.7 ± 6.6 mm
were calculated based on two measurements per 4 sectors. Measurement repeatability
calculated as intraclass correlation coefficients between two measurements at
the same cervix sector on pregnant women was found
to be 0.97 for cervical elasticity and 0.93 for the cervical length. The 95%
limits of agreement of 1) cervical elasticity were from ?22.4% to +14.9%, and 2)
cervical length from ?13.3% to +16.5%. Conclusions: This
study demonstrated clinically acceptable measurement performance and reproducibility.
The availability of stress-strain data allowed the computation of cervical
elasticity and length. This approach has the potential to provide cervical
markers to predict spontaneous preterm delivery.