Residual stone fragments and/or gravel following extracor- poreal shock wave lithotripsy (SWL) or retrograde intrarenal surgery (RIRS) constitute a real challenge to the endourolo- gists in clinical practice due to the high risk of stone re- growth, infection, obstruction as well as new stone forma- tion. Although these fragments may pass spontaneously with conservative measures in a considerable percentage of the cases; this process may affect the patients’s quality of life with the possible obstruction and distressing colic pain in most cases. Keeping this fact in mind, several non- invasive therapeutic strategies, including mechanical per- cussion, forced diuresis, body inversion (PDI), ultrasound waves and prototype magnetic tool have been introduced and applied in an attempt to facilitate the passage of these residual fragments after above mentioned minimal invasive stone management procedures. However, clinical efficacy of those measures remains really controversial [1].

Regarding this issue, researchers in China have worked on and designed a novel non-invasive device to promote active fragment discharge from the urinary system [2]. The main principle of this newly designed “External Physical Vibra- tion Lithecbole (EPVL)” system is to ease the separation of the stone fragments (residing after endourological proce- dures) from the renal collecting system by exerting simple harmonic motion to the case on the table. In addition to the movement of the cases, a multidirectional harmonic vibra- tion wave producing handle was used simultaneously to push the separated fragments forward out of the renal collecting system. Thus, through the combination of active positional change (in different directions) with an extracorporeal physi- cal vibration to the involved lumbar area of the cases, an active and effective discharge of the stone fragments residing

in different but particularly lower calyceal part of the treated kidney was aimed.

It is very clear and concise that for any newly designed and introduced technique to be well accepted, it should be first safe and also efficacious. Related with this issue, data obtained from several clinical studies have proved well with high-level evidence that the EPVL is a safe, simple, effec- tive, and non-invasive method to facilitate the spontaneous passage of the residual fragments detected after RIRS or ESWL [2–6]. Of the published data with this system so far, Wu et al. [2] were able to demonstrate that EVPL as a sup- plement to RIRS could be more effective than RIRS alone by shortening the time period for stone clearance, increasing complete stone-free rates with good patient compliance and acceptance. Further supporting these findings, Zhang et al.

[5] were able to show that the best time to perform EPVL is 3 days after RIRS procedure for the highest stone-free rates at any point in time with meaningfully reduced complica- tions caused by these fragments. Last but not least, in their original studies, Long et al. [3], Wu et al. [6], and Tao et al. [4], all reported well that EPVL could facilitate the sponta- neous discharge of residual stone fragments with a meaning- fully shortened expulsion time after SWL. Thus all these data clearly indicate that the EPVL system can be regarded as an adjunctive active treatment modality particularly for residual stone fragments after RIRS and SWL procedures in an outpatient service manner.

Despite its first description a few years ago, EPVL sys- tem has yet to gain widespread popularity and acceptance by the endourologists. This modality will certainly prove itself to be as a new “adjunctive treatment” option to man- age the residual stone fragments in cases undergoing above mentioned commonly performed procedures. Initial results

Funding None.

Compliance with ethical standards

Conflict of interest Prof.Kemal SARICA is acting as a consultant for Dornier GmbH company.

Ethical approval This article does not contain any studies with human participants performed by any of the authors.

References

1. Chiong E, Tay SPH, Li MK, Shen L, Kamaraj R, Esuvaranathan K (2005) Randomized controlled study of mechanical percussion,diuresis, and inversion therapy to assist passage of lower pole renal calculi after shock wave lithotripsy. Urology 65:1070–1074

2. Wu W, Yang Z, Xu C, Gu X, Yang S, Liao S, Wang R, Gao W, Ye Z, Zeng G (2017) External physical vibration lithecbole promotes the clearance of upper urinary stones after retrograde intrarenal surgery: a prospective, multicenter, randomized controlled trial. J Urol 197:1289–1295

3. Long Q, Zhang J, Xu Z, Zhu Y, Liu L, Wang H, Guo J, Wang G(2016) A Prospective randomized controlled trial of the efficacy of external physical vibration lithecbole after extracorporeal shock wave lithotripsy for a lower pole renal stone less than 2 cm. J Urol 195:965–970

4. Tao R, Tang Q, Zhou S, Jia C, Lv J (2020) External physical vibration lithecbole facilitating the expulsion of upper ureteric stones 1.0–2.0 cm after extracorporeal shock wave lithotripsy: a prospective randomized trial. Urolithiasis 48:71–77

5. Zhang Y, Xu C, Wang Y et al (2019) When is the best time to perform external physical vibration lithecbole (EPVL) after ret-rograde intrarenal surgery (RIRS): a multi-center study based on randomized controlled trials. Urolithiasis. https ://doi.org/10.1007/ s0024 0-019-01175 -5

6. Wu W, Yang Z, Tang F et al (2018) How to accelerate the upper urinary stone discharge after extracorporeal shockwave lithotripsy (ESWL) for %3c 15 mm upper urinary stones: a prospective multi-center randomized controlled trial about external physical vibra-tion lithecbole (EPVL). World J Urol 36:293–298

Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.