Urolithiasis refers to all types of stones that form in the urinary system, typically originating in the kidneys. Stones formed in the kidneys travel along the ureters, bladder, and urethra, obstructing the flow of urine and causing pain in the surrounding areas. In this process, complications such as urinary tract infections (UTIs), hydronephrosis (swelling of the kidney due to urine backup), and even renal failure (decreased kidney function) can occur.
When urolithiasis occurs, extracorporeal shock wave lithotripsy (ESWL) is usually attempted first. ESWL does not require hospitalization or anesthesia, and daily life can be resumed almost immediately, typically within about an hour after the procedure. However, not all stones can be resolved with ESWL. In the following cases, it is advisable to consider ureteroscopic stone removal.
First, when complications such as renal failure, hydronephrosis, or urinary tract infection have occurred. If renal failure, characterized by decreased kidney function, develops, endoscopic surgery should be considered. ESWL is a method that breaks stones into fragments using shock waves, which are then naturally expelled with urine. However, if kidney function is impaired, urine flow is often poor. Consequently, natural expulsion becomes difficult in such circumstances.
If a urinary tract infection occurs, it is advisable to remove the stone in a single procedure before the inflammation worsens. Therefore, considering ureteroscopic stone removal instead of ESWL is more effective.
Secondly, in cases of special types of stones such as radiolucent stones, bilateral ureteral stones, or multiple stones, ureteroscopic stone removal should be considered. In the case of radiolucent stones, the stones are not visible on X-rays. This makes it difficult to perform ESWL, which relies on X-ray fluoroscopy to guide the treatment. For bilateral ureteral stones, where both the left and right ureters are simultaneously obstructed, it is a dangerous situation that can lead to acute renal failure if urine is not expelled from both sides. Therefore, it is difficult to wait for 2-3 sessions of lithotripsy to be completed.
Furthermore, if there are multiple stones in one ureter (multiple calculi), even if one stone is fragmented, the remaining stones will still be present, making expulsion difficult. Therefore, in such cases, it is advisable to proceed with ureteroscopic stone removal rather than ESWL.
If the stone size is large, exceeding 1 cm, proceeding directly with endoscopic surgery can be more effective. For large stones larger than 1 cm, the probability of successful fragmentation with a single session of ESWL is significantly low. This means multiple lithotripsy sessions would be required. However, ESWL must be performed with an interval of about 5 days to a week, considering the impact on the body. Consequently, the treatment period inevitably becomes prolonged. During this extended period, as the large stone continues to obstruct the ureter, kidney function progressively declines, and severe pain persists. Therefore, for large stones exceeding 1 cm, removal in a single procedure via endoscopic surgery is faster and more effective.
Urolithiasis causes severe pain, often compared to the pain of childbirth. Therefore, if ESWL has not been effective, it is recommended to consider ureteroscopic stone removal, which can remove the stone in a single procedure. Recently, with the advancement of surgical equipment, including rigid and flexible endoscopes, safer and more effective surgeries have become possible.