Reviewer's Choice

Ben H Chew et al., 2024: Break Wave Lithotripsy for Urolithiasis: Results of the First-in-Human International Multi-Institutional Clinical Trial

Thursday, 05 December 2024

216 Hits

Ben H Chew 1, Jonathan D Harper 2, Roger L Sur 3, Thomas Chi 4, Shubha De 5, Anne R Buckley 6, Ryan F Paterson 1, Victor K F Wong 1, Connor M Forbes 1, M Kennedy Hall 7, Ross Kessler 7, Seth K Bechis 3, Jason R Woo 3, Ralph C Wang 8, David B Bayne 4, Derek Bochinski 5, Trevor D Schuler 5, Tim A Wollin 5, Rahim Samji 5, Mathew D Sorensen 2
1Department of Urological Sciences, University of British Columbia, Stone Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada.
2Department of Urology, University of Washington School of Medicine, Seattle, Washington.
3Department of Urology, University of California San Diego, San Diego, California.
4Department of Urology, University of California San Francisco, San Francisco, California.
5Department of Urology, University of Alberta, Edmonton, Alberta, Canada.
6Department of Radiology, University of British Columbia, Stone Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada.
7Department of Emergency Medicine, University of Washington School of Medicine, Seattle, Washington.
8Department of Emergency Medicine, University of California San Francisco, San Francisco, California.

Abstract

Purpose: This study reports on a prospective, multicenter, single-arm, clinical trial utilizing the SonoMotion (San Mateo, California) Break Wave lithotripsy (BWL) device to fragment urinary stones.

Materials and methods: Patients with a urinary stone underwent a single treatment of 30 minutes and peak negative pressure of 4.5 to 8 MPa. Subjects were contacted and outcomes assessed at 7, 14, and 35 days after treatment, with clinical follow-up and CT imaging 70 ± 14 days postprocedure. The primary objectives were to assess the safety (hematomas, complications, etc) and effectiveness of BWL (any fragmentation, residual fragments ≤4 mm or ≤2 mm, and completely stone-free rate) as assessed via noncontrast CT-kidneys, ureters, and bladder.

Results: Forty-four patients with a ureteral (43%) or renal (57%) stone were treated across 5 centers. Stone fragmentation occurred in 88% of cases; 70% had fragments ≤ 4 and 51% ≤ 2 mm, while 49% were completely stone free on CT; no serious adverse events were reported. Eighty-six percent of patients received either no analgesic medication at all (50%) or minor analgesia (36%). After determining optimal therapy settings, 36 patients were treated and the effectiveness improved exhibiting fragmentation in 92% (33/36), residual fragments ≤ 4 mm in 75% and 58% with fragments ≤ 2 mm with 58% completely stone free. Effectiveness was less in subjects with lower pole stones with 81% fragmentation, 71% having fragments ≤ 4 mm, 29% with fragments ≤ 2 mm, and 29% completely stone free; of distal ureteral stone patients, 89% were completely stone free.

Conclusions: BWL offered safe and effective noninvasive stone therapy requiring little to no anesthesia and was carried out successfully in nonoperative environments.

J Urol. 2024 Oct;212(4):580-589. doi: 10.1097/JU.0000000000004091. Epub 2024 Sep 10.
PMID: 39254129

Comments 1

Hans-Göran Tiselius on Thursday, 05 December 2024 10:00

This article reports the first clinical results of BREAK WAVE LITHOTRIPSY, an ultrasound-based technique for stone-disintegration. This new method corresponds to urologists’ wish to carry out stone disintegration without anesthesia, analgesics or sedatives. In the reported series 50% were treated without any medication.
One great advantage is that the method is based on ultrasound both for stone identification and stone disintegration. Avoiding radiation is a great step forward, but there is a need of ultrasound skill by the operator. Unfortunately, ultrasound limits the applicability of the method because the authors state that 31 of 75 selected patients had to be excluded!
Only small stones were treated with this method, size mean (SD) 6.1 (1.5) mm.
The fragmentation was good. 51% of the patients had fragments up to 2 mm and as many as 49% were stone-free. It is difficult to interpret the result, but Table 3 shows that 70% of the patients were either stone-free or had residuals not larger than 4 mm.
The authors distinguish between overall results and “optimal dose” results. With both settings 89% of the distal ureteral stones were cleared.
One interesting note is that the hit-rate was improved by cooperation with the patient. who learnt how to breathe in a way aiming at maintaining the stone in focus. It is difficult, however, to know to which extent this trick was possible to use and in how many patients.
Break wave lithotripsy is one of few innovations in non-invasive stone disintegration since introduction of SWL 1980. It will be highly interesting to see how successful this method will be with larger stones and in a larger group of patients.
It is obvious, however, that the ultrasound technology has certain limitations, but it also is evident that in small stones in need of immediate treatment, break wave lithotripsy is a promising and interesting new tool.

Hans-Göran Tiselius

This article reports the first clinical results of BREAK WAVE LITHOTRIPSY, an ultrasound-based technique for stone-disintegration. This new method corresponds to urologists’ wish to carry out stone disintegration without anesthesia, analgesics or sedatives. In the reported series 50% were treated without any medication.
One great advantage is that the method is based on ultrasound both for stone identification and stone disintegration. Avoiding radiation is a great step forward, but there is a need of ultrasound skill by the operator. Unfortunately, ultrasound limits the applicability of the method because the authors state that 31 of 75 selected patients had to be excluded!
Only small stones were treated with this method, size mean (SD) 6.1 (1.5) mm.
The fragmentation was good. 51% of the patients had fragments up to 2 mm and as many as 49% were stone-free. It is difficult to interpret the result, but Table 3 shows that 70% of the patients were either stone-free or had residuals not larger than 4 mm.
The authors distinguish between overall results and “optimal dose” results. With both settings 89% of the distal ureteral stones were cleared.
One interesting note is that the hit-rate was improved by cooperation with the patient. who learnt how to breathe in a way aiming at maintaining the stone in focus. It is difficult, however, to know to which extent this trick was possible to use and in how many patients. 
Break wave lithotripsy is one of few innovations in non-invasive stone disintegration since introduction of SWL 1980. It will be highly interesting to see how successful this method will be with larger stones and in a larger group of patients.
It is obvious, however, that the ultrasound technology has certain limitations, but it also is evident that in small stones in need of immediate treatment, break wave lithotripsy is a promising and interesting new tool.

Hans-Göran Tiselius

Cancel Update Comment