Topographic and anatomical peculiarities of the pyelocaliceal system of the kidney in the fetal period of human ontogenesis

Abstract

Abstract renal pyelocaliceal system (RPCS) during the fetal period of human intrauterine development (IUD) is important for elucidating and understanding the complex transformations of their structure, syntopy and skeletotopy, in particular, to explain the causes and time of appearance of the structural variants and congenital malformations of the organ. Material and methods: A total of 102 human fetal biomanikins of 160.0-480.0 mm parietal-coccygeal length (PCL) (4-10 months of IUD) were studied. A complex of methods of morphological research was applied. Results: It was found a lobar structure of the kidneys of human fetuses on all specimens. Two main variants of their external structure were revealed – bean-shaped and oval-shaped. Two variants of the structure of the renal hilum were observed – their open and compact forms. Among the variants of the structure of the RPCS, we observed ampullary and branched types. Syntopy of the renal pelvis and pyelo-ureteral segment with renal vessels on the right and on the left is almost the same, and in the dynamics of the fetal period of IUD does not change significantly. Conclusions: 1. The topography of the renal calyx-pelvic system is largely determined by the peculiarities of the spatial structure of the kidney – its external shape, size, skeletotopy, individual features of the hilum of the organ, their syntopy with the renal vessels. 2. Close syntopy of the renal pelvis and pyelo-ureteral segment with renal vessels with a compact form of the renal hilum may be an anatomical prerequisite for impaired urodynamics, provided there are variants of renal vessels branching or the existence of an abnormal vessel in the renal hilum region. 3. Variants of the structure of the kidneys and their structures are clearly observed from the beginning of the fetal period of human IUD, significantly affect the topography of the calyces and pelvis, and in some cases can cause impairment of urodynamics.