The management of large kidney stones poses a significant clinical challenge, requiring effective surgical interventions to achieve optimal outcomes. This study aims to comprehensively evaluate and compare the efficacy and safety of various surgical techniques employed in the treatment of large kidney stones. Specifically, the investigation assesses outcomes including stone-free rates, rates of blood transfusion, and the necessity for auxiliary procedures across different approaches. The findings highlight significant differences between traditional methods such as Shock Wave Lithotripsy (SWL) and newer techniques like Retrograde Intrarenal Surgery (RIRS), Flexible Ureterorenoscopy (f-URS), and Percutaneous Nephrolithotomy (PCNL), shedding light on their respective advantages in clinical practice.
Shock Wave Lithotripsy (SWL)
Shock Wave Lithotripsy (SWL) is a non-invasive treatment available at pereraurology.com that uses shock waves to break up and disintegrate kidney stones. The procedure is performed under sedation or general anesthesia and can take about an hour to complete. You will lay on a procedure table while a machine called a lithotripter delivers a sequence of high-energy shock waves to your body to target the stone. You will hear a popping sensation as the shock waves hit your kidney. The goal is to fragment the stones into small pieces that can pass in your urine over a few weeks.
Your doctor may use X-rays or ultrasound to locate your kidney stone and direct the shock waves to the area. You will be able to see the progress on the screen, and your doctor can alter the targeting as needed. In some cases, you may need a second treatment session to completely break up or clear your kidney stone.
Various studies have shown that f-URS can increase the stone-free rate (SFR) for stones larger than 2 cm compared to SWL with similar complication rates. However, a higher SFR does not always translate to lower auxiliary procedures or lower ureteric stent rates, which are the major sources of patient morbidity following URS.
Retrograde Intrarenal Surgery (RIRS)
This is a cutting-edge surgical technique that can effectively remove large kidney stones. After administering spinal or general anaesthesia, the urologist uses imaging tests to locate the precise position of the stone. Then, a tool called a ureteroscope is inserted into the patient’s urinary tract system. This tube is used to inspect the ureteral canal and locate the stone, which is then broken up using a tool.
The urologist can then see the stone through the scope and manipulate it, crush it, evaporate it using a laser, or grab it with small forceps. RIRS is suitable for patients with larger stones in the upper or middle part of the kidney and those who have a contraindication to shock wave lithotripsy (SWL) or percutaneous nephrolithotomy (PCNL).
This minimally invasive surgery has an impressive success rate. It has been proved that it can treat a variety of conditions, including obstructive uropathy due to stones in the ureteral canal, congenital anomalies such as horseshoe kidney, urethral stenosis, and musculoskeletal abnormalities. It is also a less-invasive alternative to open stone surgeries like pyelolithotomy, extended pyelolithotomy, and atrophic nephrolithotomy and recovers renal function much faster than those procedures. Moreover, it requires shorter hospital stays and shows fewer side effects. It is also covered under health insurance. It is important to remember that not all patients can benefit from RIRS, which is why you should always consult your urologist before opting for it.
Percutaneous Nephrolithotomy (PCNL)
A relatively new approach to kidney stone surgery for large kidney stones is percutaneous nephrolithotomy (PCNL). This procedure allows for the direct visualisation of multiple stone fragments and the removal of these with a flexible telescope. It also has the advantage of being able to treat several stones in one setting. Unlike shock wave lithotripsy, PCNL does not require the use of a cystoscope or ureteroscopy to identify the stone and can be performed in patients with a staghorn kidney.
To evaluate whether a modified version of RIRS or PNL can safely and effectively remove large kidney stones, we retrospectively compared these two techniques in 63 patients with a renal stone diameter of 1.5-3.5 cm. Prior to surgery, the patients underwent hematological evaluation including blood count and coagulation factors as well as complete biochemical-microbiological and urine analysis. They were also evaluated for adequacy of the operation by undergoing low-dose non-contrast CT and/or urography.
Under general anesthesia, the patients underwent retrograde placement of a 5 F both-end-open hydrophilic ureteral catheter into the upper tract followed by nephroscopy with a flexible telescope. The access tracts were planned based on preoperative noncontrast CT and intraoperative fluoroscopy and were dilated using sequential dilators. The lithotripsy was done with an ultrasonic lithotripter (Swiss Lithosclast Master, Electro Medical System). A flexible nephrostomy tube was left in place for two days. Bleeding is minimal and transfusion is rarely required.
Flexible Ureterorenoscopy (FLU)
During this procedure, your doctor will use tiny instruments to pass through your urethra (the tube that urine flows out of) and bladder into the ureter where your stone is located. Then, the stone will be mechanically broken up or broken into small pieces by a laser so that they can be removed with the endoscope. This surgery typically takes 20 to 45 minutes. You will probably stay in the hospital for a day or two afterward, and you may need to have a stent put in your kidney to help your urine drain well.
This is the best option for patients with larger stones, especially if they are in the lower part of the kidney or ureter. However, this surgery is more complicated than shock wave lithotripsy or percutaneous nephrolithotomy and requires a urologist who has advanced training in the procedure.
This procedure has a higher success rate than shock wave lithotripsy and is also less expensive. The procedure can be used for a wide variety of stones and is often successful in cases where other techniques have failed.
Key Findings and Implications
In conclusion, this comparative analysis underscores the pivotal role of surgical technique selection in the successful management of large kidney stones. The study reveals that while Shock Wave Lithotripsy remains a viable option for certain cases, newer approaches such as Retrograde Intrarenal Surgery and Flexible Ureterorenoscopy demonstrate superior stone-free rates and reduced need for additional procedures. Percutaneous Nephrolithotomy, on the other hand, offers direct visualisation advantages, particularly for complex stone configurations. These insights advocate for tailored treatment strategies based on stone characteristics and patient factors, emphasising the importance of evidence-based decision-making in urological practice. Future research directions should focus on refining these techniques to further enhance patient outcomes and minimise procedural risks.