ANATOMICAL JUSTIFICATION OF ULTRASOUND SECTIONS THROUGH FOUR CHAMBERS OF THE HEART AND LUNGS IN FETUSES 18-22 WEEKS OF DEVELOPMENT ON SECTIONAL MATERIAL

The objective is to give a descriptive and quantitative characterization of the organs and structures of the chest in 18-22 weeks of development human fetuses on sections correlating with ultrasound sections through four chambers of the heart and lungs.

Material and methods. In the course of the study, sections of 10 torsos of fetuses of both sexes were studied at 18-22 weeks of gestation without signs of pathology. The fetuses were obtained as a result of interruption of physiological pregnancy in healthy women for social reasons in compliance with ethical and deontological norms. The study was carried out using the following methods: macromicroscopic preparation, the N.I. Pirogov method of cuts, histotopographic method, morphometry method, followed by statistical data processing.

Results. Three groups of sections were performed and described during the study: a section at the level of the Th_V lower border, at the level of the Th_VI-Th_VII disk and at the level of the Th_VII body. The sections were obtained in planes corresponding to ultrasound images conducted through four chambers of the heart and lungs (according to International Society of Ultrasound in Obstetrics and Gynecology recommendations). It was revealed that the largest number of heart internal structures is visualized on a section at the level of the Th_VI-Th_VII vertebrae disk. At this level, the anteroposterior and transverse dimensions of the section were 41.9±0.5 mm and 47.3±0.8 mm respectively. The dimensional characteristics of the heart had the greatest values in this section: the longitudinal size of the heart was equal to 23.1 ± 0.5 mm, the transverse size was 21.26 ± 0.6 mm. Based on this, it is advisable to perform ultrasound sections with skeletotopic reference to the level of the Th_VI-Th_VII intervertebral disc during screening ultrasound examination of fetuses in the second trimester. At the same time, the levels of the Th_V lower border and the Th_VII body allow to receive a more detailed study of other organs and structures of the chest visualized on these sections (lungs, esophagus, descending aorta, thoracic vertebrae).

Conclusions. The combination of ultrasound examination based on a fundamental anatomical database will improve the diagnosis of congenital malformations during screening.

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