Clearance of Stone Fragments and Stone Dust by Continuous Flow Hydrodynamics in Percutaneous Renal Surgery: An In Vitro Study

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.

Which way is best for stone fragments and dust extraction during percutaneous nephrolithotomy

Percutaneous nephrolithotomy (PCNL) is a commonly used type of minimally invasive treatment in kidney stone surgeries. Surgical success is assessed according to residual stone amount after surgery. The purpose of this study is to compare the two methods' success and practicality that are applied after the fracture of the stone in the patients who applied PCNL and which enable the removal of the residual stones. Among 102 patients who underwent a single-session of PCNL at our department between June 2015 and November 2016 were evaluated. Previously identified irrigation method and our aspiration method which described used in post-operative patients divided into two groups of residual fragments was assessed by computed tomography. The results were evaluated in statistical analyses. Significant p was accepted as p < 0.05. The age and gender distribution of patients in the irrigation and aspiration groups did not differ significantly (p > 0.05). In irrigation and aspiration groups, stone size did not differ significantly (p > 0.05). The amount of residue stones and dust remaining in the irrigation group was significantly higher (p < 0.05) than the aspiration group. Although many methods have been tried before, we think that the aspiration method we have described is a cheaper, more effective and feasible option.