Sometimes, for various reasons, there may be a violation of the outflow of urine from the ureter. This can happen due to displacement of kidney stones, blood clotting, etc.
Destination
The ureteral stent is designed to restore the flow of urine. This is an easily bent tube that will be placed in the ureter. It serves to remove urine to the external environment past the bladder. A ureteral stent is placed for certain kidney infections and complex surgeries.
Device
The length of the stent reaches 30 cm with a tube diameter of up to 6 mm. In order for the urinary catheter to be securely fixed, one of its ends is equipped with a spiral, which is otherwise called a "pig's tail". The device is installed using a cystoscope or ureteroscope. The ureteral stent is made of polyurethane or silicone. Its surface should be smooth, it should not be exposed to urine, not covered with s alts. Silicone proved to be the most resistant to fracture and s alt encrustation, but due to its high flexibility, the tube is difficult to fix and hold in the required position. To reduce the reactivity of the stent, it is treatedhydrogel coating. This increases the life of the appliance.
Complications after stent placement
Patients complain of dysuria, frequent urination, involuntary urge to urinate, nocturia. These phenomena are observed more often immediately after the installation of the catheter, sometimes very pronounced. To avoid removal of the stent, antispasmodics are prescribed. A decrease in the intensity of symptoms is observed after a few days. Sometimes patients complain of pain in the side and abdomen. The cause of pain in the side is reflux of urine when urinating. An installed ureteral stent sometimes causes an infectious inflammation of the urinary tract. To prevent complications, antibiotics are prescribed, although it is undesirable to use them for a long time, as resistant microorganisms may develop.
Proximal migration is a serious complication that occurs when a very short stent is placed with suboptimal twisting of the distal end or when the upper calyx is injured by the proximal end. If the stent is in the ureter for a long time, fragmentation may occur.
The fragmented ureteral stent is to be removed by ureteroscopy, cystoscopy or through the skin.
Application
The ureteral stent is used to stent the ureter in the presence of obstruction of the renal system, i.e. if there is a problem with the outflow of urine from the kidneys. The reasons can be different - urological, non-urological and iatrogenic. Tourological include urolithiasis, neoplasms in the ureter, prostate or bladder, prostate adenoma, retroperitoneal fibrosis. Obstruction, which does not belong to the field of urology - compression and germination of tumors of other localization into the ureters, various lymphomas and lymphadenopathy. Iatrogenic causes are adhesive processes after operations that were performed on the pelvic organs, as well as after radiation therapy.
