Fig. 1. Measurements and ROI definitions in elastography images. (A) CL measurement using 6-MHz transvaginal probe in B-mode ultrasonography. Measurement areas of E-Cervix. (B) Strain values of the IOS and EOS are measured using a 1-cm radius from IOS, and EOS, respectively. (C) Values of strain mean, hardness ratio, and ECI are measured from within 0.5/1.0/1.5 cm area of the cervical canal. The patient agreed to publication of the elastography image of the uterine cervix.

ROI = regions of interest, CL = cervical length, IOS = internal os of cervix, EOS = external os of cervix, ECI = elasticity contrast index.