Does combined lithotripter show superior stone-success rate than ultrasonic or pneumatic device alone during percutaneous nephrolithotrotomy? A meta-analysis.

Objectives: To compare the stone clearance rate and stone-success rate among lithotripter with ultrasonic lithotripter alone, pneumatic lithotripter alone and combined mechanisms.

Methods: Up till 2021 May, we conducted a literature search among several widely used database around the world, including Pubmed, Embase (Ovid Version), Medline (Ovid Version) and Cochrane Central Register of Controlled Trials. Only English literature was considered. Pediatric patients were excluded. Reviews and protocols without any published data were excluded. Conference abstracts and articles with unrelated contents were also excluded.

Results: Fifteen articles were included in our final meta-analysis, with 9 RCTs and 6 cohort studies. In Lithoclast combined with ultrasonic device vs pneumatic device subgroup, overall stone-success rate yielded insignificant difference. As for subgroup of Shock Pulse vs pneumatic device, pooled analysis yielded a higher 1-month stone-success rate for Shock Pulse (RR = 1.10, 95% CI: 1.01-1.19). In Lithoclast combined with ultrasonic device vs ultrasonic device subgroup and Cyberwand vs ultrasonic device subgroup, both overall stone-success rate did not differ from one another. We found Lithoclast with ultrasonic device was more efficient in stone clearance rate than pneumatic device (mean difference = 8.23, 95% CI: 4.99-11.47). The same situation was applied to the comparison between Lithoclast with ultrasonic device and ultrasonic device (mean difference = 13.02, 95% CI: 4.57-21.46).

Conclusions: Combined lithotripter was more efficient in clearing stones than pneumatic or ultrasonic device alone. However, when it came to stone-success rate, no obvious superiority was seen in combined one.