Dusting versus fragmentation for large proximal ureteral stones during flexible ureteroscopy: A prospective randomized study

Abstract

Background: Recent advances in endoscopic technology have empowered urologists to treat most types of stones within the urinary tract effectively. Available treatments for ureteral stones using a laser lithotripter include fragmentation, the active removal of fragments with a basket, and dusting. To date, only a few prospective randomized studies have endorsed the use of stone dusting, fragmentation, and active removal for ureteric stones.

Materials and methods: This randomized, prospective, comparative study was conducted in the Urology Department. Sixty patients with proximal ureteral stones from July 2019 to July 2020 were included and randomly divided into 2 groups using a random number generator program (version 2, 2015). In Group 1, the stones were fragmented into dust (n = 30), and in Group 2, lithotripsy produced extractable fragments (n = 30).

Results: In this study, the Ho:YAG laser was used to dust stones at low energy and high frequency (0.4-0.6 J and 20-30 Hz). Using the Ho:YAG laser set to high energy and low frequency (1.5-2 J and 8-10 Hz), stone fragmentation was achieved. The mean stone size was 1.63 cm in Group 1 and 1.69 cm in Group 2. The stone-free rates for the dusting and fragmentation groups were 96.6% and 86.6%, respectively. Meanwhile, the mean operative time was 87.6 ± 33.6 minutes in the dusting group and 80.4 ± 28.8 minutes in the fragmentation group. There were no postoperative complications with the dusting technique, compared with a 13.3% complication rate with the fragmentation technique.

Conclusions: For proximal ureteral stones, the stone-free rates between the dusting and fragmentation procedures were comparable. Both techniques proved to be effective.

Keywords

Proximal ureteral stones / Dusting technique / Fragmentation technique

Acknowledgments

None.

Statement of ethics

The study protocol was approved by the ethics committee of Kasr Al Ainy hospital, Cairo University (IRB number: MS-193). Written informed consent was obtained from all participants. All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Conflict of interest statement

The authors have no conflicts of interest to declare.

Funding source

This manuscript did not receive any funding.

Author contributions

SM: Paper writing; AE: Data collection and analysis; IN: Paper writing; ME: Paper revision & surgeon; SAR: Paper revision; KD: Surgeon.

Data availability

The data used in this study are available only upon request. All data generated or analyzed during this study are included in this article. Further inquiries can be directed to the corresponding author responsible for data collection and statistical analysis.

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