What are the benefits of an ureteral stent? Are there any risks?

Whether or not to place a ureteral stent depends on the individual’s specific circumstances. If there is ureteral stone‑induced stricture or stricture resulting from laser lithotripsy, such a stent may be indicated. Typically, these stents can remain in place for an extended period; however, spastic strictures lack any particularly effective treatment. Consequently, long‑term stenting is often necessary; otherwise, renal dysfunction may ensue. At present, no truly satisfactory therapeutic approach exists in domestic clinical practice.

Ureteral stenting is a minimally invasive, safe, and effective treatment for incomplete ureteral obstruction. It does not require an external fistula and has minimal impact on the patient’s quality of life. Ureteral obstruction can result from various causes, including compression by abdominal or pelvic tumors, intra-abdominal adhesions following surgery, and ureteral kinking. Such obstruction prevents the smooth drainage of urine produced by the kidneys, increasing intrarenal pressure, damaging renal cells, and leading to progressive renal dysfunction. Additionally, partial ureteral disruption can also be managed with ureteral stenting.

The principle of percutaneous ureteral stenting is to perform a percutaneous puncture of the affected renal pelvis under local anesthesia, insert a guidewire and catheter, and then advance a ureteral stent along the guidewire to establish communication between the renal pelvis and the bladder, thereby facilitating the unobstructed drainage of urine.

Ureteral stents must be replaced every 2–3 months after implantation; otherwise, they can become obstructed by urinary crystals, rendering them ineffective. Due to differences in male and female anatomy, it is easier for female patients to change their ureteral stents via the urethral meatus, whereas male patients require auxiliary instruments such as a cystoscope to perform the replacement.

However, for cases of complete obstruction or complete rupture where stent placement is not feasible, percutaneous nephrostomy may be used as an alternative treatment. The human ureter is a slender tube that transports urine from the kidney to the bladder via segmental peristaltic contractions of its smooth muscle, after which the urine is expelled from the body. In adults, the normal internal diameter of the ureter is approximately 6 mm; however, if structural changes within the ureter or alterations in surrounding tissues lead to narrowing of its lumen, this condition is referred to as ureteral stricture in medical terms. Such stricture can impede urinary flow and even result in obstruction—much like a household drain that becomes corroded and deformed, leading to poor drainage.

Placing a stent for ureteral stones carries certain risks, such as ureteral perforation, ureteral inflammation, and ureteral stricture. In general, the risks associated with a ureteral stent are relatively low; the procedure aims to support and drain the ureter. For example, a ureteral stent is often placed after surgery for ureteral or renal stones, typically under general anesthesia. If the stent is inserted under local anesthesia, the patient may experience some discomfort, which is usually tolerable.