Methodological aspects of the development of topographic-anatomical segmentation of the uterus in the second and third trimesters of pregnancy on MRI

Background. Magnetic resonance imaging (MRI) is a highly informative and safe method of examination during pregnancy, which helps to identify and localize pathological changes in the uterus or placenta.

Objective. The goal of the study was to develop a universal topographic-anatomical segmentation of the pregnant uterus using MRI (with possible comparison with the bony landmarks) to determine the exact localization of abnormalities in the placenta and myometrium.

Design and methods. A retrospective analysis of 96 MR images of the pelvis of pregnant women with various abnormalities in the placenta or myometrium was carried out.

Results. The results of the analysis were used to develop a universal topographic and anatomical segmentation of the pregnant uterus by a step-by-step division of the entire area of the uterine walls into 12 conditionally equivalent segments. The sides of the uterus were marked with the capital letters D (Dexter — right), A (Anterior — anterior), S (Sinister — left), P (Posterior — posterior) to define the orientation, and with lowercase abbreviations sup (=superior), med (=median) and inf (=inferior) to specify the upper, middle and lower levels, respectively.

Conclusion. MRI-based DASP segmentation analysis of MR images allows to accurately localize uterine abnormalities and can be used in clinical practice by radiologists and obstetricians when considering the delivery method.

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