A ‘ureteral stent’ or ‘ureteric stent’ is a thin, hollow tube inserted into the ureter. Ureters are thin tube-like-organs which connect kidneys to the urinary bladder, to allow urine flow from the kidney. The stent is longer than the actual ureter and tube-ends are usually coiled. These coiled ends stay in the kidney on one side, and bladder on the other side, so as to minimise chances of its displacement. The length of the stents used in an adult patients varies between 24 to 30 cm. Stents come in differing diameters or gauges, to fit different sized ureters. Stents also contain small openings in their walls towards the ends, known as ‘fenestrations’. These fenestrations aid in the passage of urine.
Sometimes, ureters can be blocked in many causes.
Ureteric stent effectively treats these problems. It is a firm tube which keeps the ureters patent and allows urine flow ‘through the stent’ as well as ‘around it’.
It can be done through the kidneys via a nephrostomy (an artificial opening made from the kidneys out to the skin.)
If you need a nephrostomy tube as well as ureteric stenting, your doctor may do both procedures at the same time. It is done by initially performing the nephrostomy and then using the nephrostomy to insert the stent into the ureters. This process is usually done in a radiology department under Ultrasound and x-ray guidance. General anaesthesia is usually not required for this and the procedure can be performed using sedation.
It depends on the original cause of the disease process. Indwelling times may range from a few days for relief of ‘ureteral oedema’ (or you can call it swelling), to the duration of the patient’s life for maintenance of ureteral patency in obstruction from neighbouring cancer. Regardless of the stent composition, manufacturers usually recommend exchange of stents at 3 to 6 month intervals, and studies have shown that the prevalence of complications increases with longer indwelling times Your consultant will be able to advise you on this.
Ureteric stents allow the passage of urine along the natural route. However, if you do not prefer this, a nephrostomy can be an alternate. However nephrostomy drains urine from the kidneys through the skin and usually a bag is attached to the skin.
Surgical intervention can sometimes be done to avoid nephrostomy or ureteric stenting.
Stents can be seen on ultrasound scan and x-rays which can be done to evaluate the function and position of stents respectively.
You will get an x-ray of the abdomen to ensure that the stent is in place. These x-rays are some times performed again to see the effects of treatment or occasionally to rule our displacement of the stent.