Comparative Evaluation Between One Ultrasonic and Two Single-Probe Dual-Energy Lithotripters: In Vitro and In Vivo Experiment in a Porcine Model

Use of artificial stones in training and laboratory studies, have we found the right material? Outcomes of a systematic review from the European School of Urology

Objective

In this review, we investigated the current literature to find out which artificial stones (AS) are available in endourology, and in which experimental and training schemes they are used.

Materials and Methods

A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Twenty-one out of 346 studies met our inclusion criteria and are presented in the current review. The inclusion criteria were the existence of AS and their use for laboratory and training studies.

Results

There is a wide variety of materials used for the creation of AS. BegoStone powder (BEGO USA, Lincoln, Rhode Island) and plaster of Paris™ were used in most of the studies. In addition, Ultracal-30 (U. S. Gypsum, Chicago, IL) was also used. Other materials that were used as phantoms were AS created from plaster (Limbs and Things, UK), standardized artificial polygonal stone material (Chaton 1028, PP13, Jet 280; Swarovski), model stones consisting of spheres of activated aluminum (BASF SE, Ludwigshafen am Rhein, Deutschland), Orthoprint (Zhermack, Badia Polesine, Italy), and a combination of plaster of Paris, Portland cement, and Velmix (calcium sulfate powder). Many experimental settings have been conducted with the use of AS. Our research demonstrated nine studies regarding testing and comparison of holmium: yttrium-aluminum-garnet laser devices, techniques, and settings. Six studies were about extracorporeal shock wave lithotripsy testing and settings. Three experiments looked into treatment with percutaneous nephrolithotomy. Additionally, one study each investigated imaging perioperatively for endourological interventions, stone bacterial burden, and obstructive uropathy.

Conclusion

AS have been used in a plethora of laboratory experimental studies. Independent of their similarity to real urinary tract stones, they present a tremendous potential for testing and training for endourological interventions.

Assessment of single-probe dual-energy lithotripters in percutaneous nephrolithotomy: a systematic review and meta-analysis of preclinical and clinical studies

PURPOSE

To evaluate the safety and efficacy of single-probe dual-energy (SPDE) lithotripters in patients undergoing percutaneous nephrolithotripsy (PCNL) through a systematic review and meta-analysis.

METHODS

We searched PubMed, Cochrane Library, Scopus and Embase databases until July 2022 for any preclinical or clinical studies, exploring the safety and efficacy of different SPDE lithotripters in patients undergoing PCNL. We performed a meta-analysis to compare stone-free rate, bleeding, or other complications and mean operative time between SPDE lithotripters and other lithotripters (PROSPERO: CRD42021285631).

RESULTS

We included 16 studies (six preclinical, seven observational and three randomized with 625 participants) in the systematic review and four in the meta-analysis. Preclinical studies suggest that SPDE lithotripters are safe and effective for the management of renal stones. Among clinical studies, four studies assessed Trilogy with no comparative arm, two compared Trilogy or ShockPulse with a dual-probe dual-energy lithotripter, two compared Trilogy with a laser, one compared ShockPulse with a pneumatic lithotripter, and one directly compared Trilogy with ShockPulse. Comparing SPDE lithotripters to other lithotripters, no significant differences were demonstrated in stone free rate (OR 1.13, 95% CI 0.53-2.38, I² = 0%), postoperative blood transfusion (OR 1.33, 95% CI 0.34-5.19, I² = 0%), embolization (OR 0.45, 95% CI 0.02-12.06), operative time (WMD: 2.82 min, 95% CI -7.31-12.95, I² = 78%) and postoperative complications based on the Clavien-Dindo classification.

CONCLUSIONS

SPDE lithotripters represent a promising treatment modality for patients requiring PCNL. Despite the initial encouraging findings of preclinical and isolated clinical studies, it seems that Trilogy or ShockPulse provide similar efficiency compared to older generation devices.

Clearance of Metal Particles After Percutaneous Nephrolithotomy with Trilogy Lithotripter

Purpose: To evaluate the clearance of metal particles produced and released in the pelvicaliceal system (PCS) during percutaneous nephrolithotomy (PCNL) with the use of the Swiss Lithoclast^® Trilogy dual-energy (EMS Urology, Nyon, Switzerland) lithotripter. Methods: An experimental in vivo study and a clinical investigation of case series were conducted. An in vivo porcine model with two pigs for lithotripsy (after inserting artificial stones into the collecting system) and two pigs for submucosal injection of metal particles (provided by the manufacturer of Trilogy) was conducted. Porcine kidney histology analysis for metal leftovers was conducted immediately or 2 weeks after the surgery. A prospective observational study design included 10 consecutive patients treated with conventional 30F PCNL or with 22F mini-PCNL technique. Only the patients with the confirmed metal particles in the PCS during the initial PCNL and the need for additional retrograde intrarenal surgery over a period of 2-4 weeks were selected. The presence of metal particles was evaluated during the second endoscopic surgery. Results: The generated metal particles during PCNL and the submucosally injected particles were not found macroscopically 2 weeks postoperatively in porcine models. No pathologic changes such as foreign body granuloma or inflammation were found. Similarly, no metal particles were observed during the second look endoscopy (n = 10). Conclusion: Metal particles observed endoscopically using the Trilogy lithotripter are cleared with no pathologic evidence of tissue damage from the metal particles 2 weeks after the procedure. Thus, the intraoperative release of any particle by the Trilogy lithotripter should not raise any safety concerns.

Lithotripsy devices for percutaneous nephrolithotomy (PNL) - new developments

PURPOSE OF REVIEW

Percutaneous nephrolithotomy (PNL) is the mainstay of surgery for renal calculi>2 cm or complex multiple calculi and is a technique that has been around since 1976. We review recent literature surrounding novel lithotripsy devices and technology used in PNL.

RECENT FINDINGS

At present, the Holmium:yttrium-aluminum-garnet (Ho:YAG) laser is widely accepted as the gold standard laser lithotripsy for PNL. SwissLithoClast Trilogy offers a range of probes with a trifecta of electromagnetic, ultrasonic energy with surgeon-controlled suction. The Olympus Shockpulse-SE is a similar lithotripter that relies on continuous ultrasonic energy with pulsed ballistic energy to break stones. Thulium Fiber Laser (TFL) offers an alternative laser energy source to the Holmium laser, which has been shown to be very effective at producing small stone fragments and dust. The Moses technology is another addition in a long list of improvements to the Ho:YAG laser, forming vaporization bubble through which more effective energy can be applied to stones.

SUMMARY

Trilogy, Shockpulse, TFL and Moses pulse modulation technology for the Holmium laser all provide improvements compared with older lithotripsy devices. In particular, they convey a safer, efficient and more effective way to manage and clear stones.