Morphology of ureter local structure and vascularisation

Abstract

The micro-anatomical structural and morpho-functional capacity of the ureter from the lumen to the exterior, depending on the predominant tissue component, is determined and guided by three tunics: the internal tunic - the epithelial conjunctive, the medial tunic - the muscular conjunctive and the external conjunctive-vascular-nervous. The latter has a significant importance in the medical-surgical management of surgical pathology and functional management of the intraoperative and postoperative ureter. This is frequently found in both normal ureters and ureteral malformations due to the well-differentiated vasculo-arterial afferent network associated with efferent vascular-venous networks. The conjunctive-vascular-nervous tunic, so nominated by us, is constituted by making continuously the connective tissue from the muscular-conjunctive tunic to the periphery and transition by discontinuity of the connective tissue of the retroperitoneal cell-adipose tissue into a lax connective plate consisting of fine collagen and elastic fibers with a varied condensation, thus anchoring the ureter in the retroperitoneal space. We consider it the “meso” of the ureter Normally, this tunic has a more intimate appearance with the ureter, whereas a considerable distance from the muscular tunic can be observed in malformations. It has been established that vasculo-nervous devices in the sheath area form a vascular plexus giving various circular and longitudinal oblique branches anastomosed and organized in a layered way, segmented or in various arborescent aspects. This plexus, a vascular carcass, directly communicates with the vasculo-nervous network of muscle and epithelial-connective tunics. Between the sheath and ureter muscles, the connective tissue is devoid of vascular anastomosis, in this area there are only afferent and efferent arterio-venous vessels that penetrate the respective area, which allows it to be detached on insignificant surfaces. The detachment of the ureteral sheath induces amputation of the afferent and efferent arterial and venous branches with the disordered local circulation at the meso-ureter level, including the ureter within the limits of the detachment. The attempts of detachment of the ureteral sheath contribute to severe circulatory disturbances in the ureteral segments meant for anastomosis, which leads to fibrosis of the ureter. The lower third of the ureter does not mobilize, but detaches from the peri.