A comparison of uterine corpus and endometrium volumes measured in 2D and 3D modes

Abstract

Objective: to compare the uterine corpus and endometrium volumes measured in 2D and 3D modes.Material and methods. The observational retrospective cohort study included 154 women of reproductive age with no myometrial or endometrial pathology. Pelvic ultrasound was performed with the use of the Affiniti70 (Philips, Netherlands) with a multifrequency 3D intracavitary probe. The uterine corpus volume and endometrial volume were measured both in 2D and 3D modes, followed by a calculation of the percentage ratio of endometrial volume to uterine corpus volume (endometrial/uterine corporeal volume ratio (EV/UCV)).Results. The values of uterine corpus volume measured in 3D mode were higher than in 2D mode, with a relative measurement error of 7.2%. The strength of the correlation turned out to be very high (r = 0.91, p = 0.458). According to the Bland-Altman plot, almost all values of the volume difference in pairwise measurements fell within the interval ±1.96 SD 95%; a low average difference indicates a low systematic discrepancy in measurements, and the degree of value scatter is quite acceptable. The values of endometrium volume in 3D mode were lower than in 2D mode; the relative error in 2D mode, regardless of the cycle phase, was -35.3%. There was a strong correlation between the two measurement methods (r = 0.81), but the differences in allocations were significant (p<0.05).Conclusion. It is permissible to use the values of the uterine corpus volume obtained in 2D mode as an analogue of 3D mode volume in routine practice, while it is not acceptable in the assessment of endometrium volume and EV/UCV.