Ultrasound estimation of the experimental stent efficacy in comparison with conventionally used ones
Objectives. To estimate sonographic changes in the stented kidney depending on the type of stent used and the terms of the drainage in the experiment. Methods. Ultrasound anatomy of the stented kidney was studied in male rabbits of Gray giant breed. In the main study group the unilateral experimental stent implantation with the external diameter of 3 Ch and length of 4cm made of nickelide-titanium wire 100 mm in diameter and protected with the original nanostructured coat containing carbon-silver was carried out. The stents were manufactured by the laboratories of the Research institute “Belgorod State National Research University”. As a control (n=10 animals), the unilateral implantation of «White-star standart» stent of the company Urotech (Germany) of the same diameter was performed. In the pre- and postoperative period the ultrasound of the kidneys using the apparatus “Aloka 3500” with the use of linear sensor of 8 Mhz was done. The morphometric size and physiology of renal blood flow were registered. Results. Ultrasound picture of the stented kidney in the control group of animals was characterized by the progression of retention changes in the upper urinary tract. The cause of retention changes of the upper urinary tract was vesico-ureteral reflux and the obstruction of the internal stent. Disturbance of the urine outflow from the upper urinary tract in the control group of animals was accompanied by sonographic signs of sclerotic changes in the stented kidney. In the main group no statistically significant differences in ultrasonic morphometric parameters and renal blood flow were registered in comparison with the initial data and the contralateral kidney (р>0,05). Conclusions. Segmental drainage of the upper urinary tract by experimental stent did not disturb physiology in the stented kidney and did not lead to the development of obstructive uropathy.