Dr. Khurshid Ghani Surgical and his Team at the Michigan Medicine, Brighton Center for Speciality Care perform a Kidney Stone Dusting with the Moses Technology surgery.
Technique Description:
Dr. Ghani demonstrates the high frequency dusting technique using the holmium laser system (P120) and Pulse modulation with Moses Technology. The Moses technology provides a multi-pulse, where the laser pulse is modulated to two sequences: the first one separates the fluid to create a vapor bubble; a second vapor bubble is then created through which the remaining part of the energy travels to result in improved energy transmission. It leads to increased fragmentation and less retropulsion. With a combination of contact (painting, dancing chipping) and non-contact (pop-dusting) laser lithotripsy, the goal is to get fragments < 1 mm in size, so that the patient can spontaneously pass these fragments to obtain optimal stone clearance.
Procedure Steps:
- 1. Cystoscopy with insertion of working and safety guidewires into the renal pelvis
- 2. Insertion of ureteral access sheath
- 3. Examination of collecting system with single use flexible ureteroscope
- 4. Placement of patient in Trendelenburg position
- 5. Insertion of 230 core ball-tip Moses laser fiber
- 6. Contact laser lithotripsy using settings ranging from 0.2-0.3J (pulse energy) and 50-80Hz (frequency)
- 7. Use of Moses Distance mode to facilitate dusting technique
- 8. Use of dancing, chipping and painting of stone to debulk the stone
- 9. Nudging of large stones from renal pelvis to calyces
- 10. Combination of contact and non-contact laser lithotripsy using Moses Distance mode
- 11. Use of pop-dusting (0.5J x 80 Hz) and pop-corning (1J x 20 Hz) techniques to pulverize stones into sub-millimeter fragments
- 12. Flushing of calyces at end with saline
- 13. Inspection of ureter on withdrawal of scope and sheath to assess for ureteral trauma
- 14. Placement of ureteral stent with extraction string for drainage, and removal at home by patient on post-op day 7
Learning Points:
- Use of multi-pulse modulation with Moses Technology using the Moses Distance mode to improve fragmentation and reduce retropulsion for dusting technique
- Settings and technique for contact phase laser lithotripsy
- Settings and technique for non-contact phase laser lithotripsy
- Parameter selection and safety aspects for high power holmium laser lithotripsy
Clinical History:
- 71-year-old female
- Seen by general urology for asymptomatic microscopic hematuria
- CTU demonstrated left sided 15 mm UPJ kidney stone, and 7 mm upper pole stone
- Urine culture negative
- Referred to Endourologist for treatment
- Decision made to perform retrograde intrarenal surgery – flexible ureteroscopy with laser lithotripsy
- No family history of kidney stones
Other History:
- Factor V Leiden trait
- Hyperlipidemia
