A Comparison of Ureteroscopic Treatment of Nephrolithiasis With and Without Moses Technology
A Comparison of Ureteroscopic Treatment of Nephrolithiasis With and Without Moses Technology
Flexible ureteroscopy is characterized as first-line therapy for the treatment of renal
 stones < 2 cm in size. This involves passing a flexible endoscope into the renal pelvis
 through the urethra, bladder and ureter in a retrograde fashion. Holmium: YAG laser remains
 the preferred energy modality to subsequently break stones of this size into fragments small
 enough to remove or pass spontaneously through the ureter. Advances in the understanding of
 laser energy delivery have led to the recent commercialization of the "Moses Effect" - the
 creation of vapor bubbles/cavities between the laser fiber tip and the target through which
 laser energy can more efficiently travel. Lumenis was the first to optimize this laser
 phenomenon and market it as "Moses Technology" in their Lumenis Pulse P120H laser system.
 This system is already FDA approved through the 510K pathway and is commercially available.
 The purpose of this study is to evaluate the potential of Moses laser technology to reduce
 operative time compared to non-Moses settings for ureteroscopic treatment of nephrolithiasis.
There is ongoing debate on the optimal means of laser stone fragmentation, and Moses
 technology is the latest advancement to raise questions regarding clinical utility. Initial
 preclinical studies demonstrated significantly reduced stone retropulsion and higher stone
 ablation volume with Moses technology, leading to the conclusion that the system allows more
 efficient laser lithotripsy. Human studies also showed that laser lithotripsy with Moses
 technology utilized laser energy in less time for stone fragmentation: 10.0 (2.6-15.0) min
 without vs 6.0 (2.8-13.0) min with Moses technology.

 Others have evaluated the cost effectiveness of Moses technology in their own cohort of 40
 patients who underwent standard laser lithotripsy by comparing a 35% projected decrease in
 procedure time against the cost of the Moses laser fiber and machine. Mean stone size was
 10.2 mm in this group of patients, and mean lasing time was 3.0 minutes. While a significant
 positive association was seen between stone size and laser time, cost analysis failed to show
 a benefit in using Moses technology across sizes.

 To date, there are limited clinical data obtained through rigorous study methodology. In
 addition, knowledge gaps remain regarding the effect of Moses technology on other clinically
 meaningful outcomes such as stone-free rate. Therefore, the investigators propose a
 multi-center, prospective, randomized, double blind clinical trial to further assess the
 effect of Moses technology for lithotripsy. The investigators aim to study a broader range of
 outcomes which will be facilitated by being the largest study to date. The investigators also
 aim to study novel outcomes such as grading retropulsion and visibility by independent
 blinded review as well as effects of Moses technology on independently reducing surgeon
 burnout. Indeed, a randomized, double blind clinical trial evaluating Moses technology in 66
 patients undergoing ureteroscopy was presented as a 2018 European Association of Urology
 abstract. While this single center study demonstrated safety and reduced fragmentation time
 as well as procedure time using Moses technology, it did not show a significant difference in
 stone-free rates. This study is also yet to be published as a manuscript.
Inclusion Criteria:

 -  Solitary renal stone 8 to 20 mm in size or in the case of multiple stones the
 conglomerate diameter (additive maximal diameter of all stones on axial imaging of
 computed tomography) of 8-20 mm is required

 -  Must be a suitable operative candidate for flexible ureteroscopy per urologic
 guidelines

 -  Must be 18 years or older

 -  Must be able to give consent

 Exclusion Criteria:

 -  Concomitant stones in the ureter

 -  Prior ipsilateral upper urinary tract reconstructive procedures or history of
 ipsilateral ureteral stricture

 -  Prior radiotherapy to the abdomen or pelvis

 -  Neurogenic bladder or spinal cord injury

 -  Pregnancy

 -  Untreated UTI