Laser lithotripsy

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Laser lithotripsy
ICD-9-CM 98
MeSH D017602

Laser lithotripsy is a surgical procedure to remove stones from urinary tract, i.e., kidney, ureter, bladder, or urethra.


Laser lithotripsy was invented at the Wellman Center for Photomedicine at Massachusetts General Hospital in the 1980s to remove impacted urinary stones. Optical fibers carry light pulses that pulverize the stone. Candela licensed the technology and released the first commercial laser lithotripsy system.[1] Initially 504 nm dye lasers were used, then holmium lasers were studied in the 1990s. Several companies currently produce holmium lasers for lithotripsy including Lumenis, DirexGroup, Trimedyne, and Electro Medical Systems.


A urologist inserts a scope into the urinary tract to locate the stone. The scope may be a cystoscope, ureteroscope, renoscope or nephroscope. An optical fiber is inserted through the working channel of the scope, and laser light is directly emitted to the stone. The stone is fragmented and the remaining pieces are washed out of the urinary tract.

The procedure is done under either local or general anesthesia and is considered a minimally-invasive procedure. It is widely available in most hospitals in the world.


Laser lithotripsy (LL) has been evalulated against Extracorporeal Shock Wave lithotripsy (ESWL), finding both to be safe and effective.[2][3] ESWL may be safer for small stones (<10 mm), but less effective for 10–20 mm stones.[2] A 2013 meta-analysis found LL can treat larger stones (> 2 cm) with good stone-free and complication rates.[4]

Holmium laser lithotripsy had superior initial success and re-treatment rate compared to Extracorporeal shock wave lithotripsy (ESWL) in a 2013 trial.[5]

The experimental Thulium Fiber Laser (TFL) is currently being studied as a potential alternative to the Holmium:YAG laser (Ho:YAG) for the treatment of kidney stones. The TFL has several potential advantages compared to Ho:YAG laser for lithotripsy, including a four times lower ablation threshold, a near single-mode beam profile, and higher pulse rates, resulting in up to four times as fast ablation rates and faster procedural times.[6]


Pulsed dye lasers with wavelength 200-550 microns[7] have been used for lithotripsy of biliary and urinary stones.[8]

Holmium:YAG lasers have wavelength of 2100 nm (infrared) and are used for medical procedures in urology and other areas. They have qualities of CO2 and Nd:Yag lasers, with ablative and coagulation effects.[9] Holmium laser use results in smaller fragments than 320 or 365 micron pulsed dye lasers or electrohydraulic and mechanical methods.[10]

Thulium fiber lasers are being investigated.[11][12][13][14][15]


  1. ^ "Research Discoveries". Wellman Center for Photomedicine. Retrieved 30 April 2011. 
  2. ^ a b "A Prospective Randomized Comparison Between Shock Wave Lithotripsy and Flexible Ureterorenoscopy for Lower Caliceal Stones ≤2 cm: A Single-Center Experience.". J Endourol. Nov 18, 2014. doi:10.1089/end.2013.0473. PMID 25203489. 
  3. ^ "Flexible Ureterorenoscopy versus Extracorporeal Shock Wave Lithotripsy for the treatment of upper/middle calyx kidney stones of 10-20 mm: a retrospective analysis of 174 patients.". Springerplus 3: 557. Sep 24, 2014. doi:10.1186/2193-1801-3-557. 
  4. ^ "Flexible ureteroscopy and laser lithotripsy for stones >2 cm: a systematic review and meta-analysis.". J Endourol. 26: 1257–63. Oct 2012. doi:10.1089/end.2012.0217. PMID 22642568. 
  5. ^ "Management of impacted proximal ureteral stone: Extracorporeal shock wave lithotripsy versus ureteroscopy with holmium: YAG laser lithotripsy.". Urol Ann. 5: 88–92. Apr 2013. doi:10.4103/0974-7796.110004. PMID 23798864. 
  6. ^ Hardy, L.A; Wilson, C.R.; Irby, P.B.; Fried, N.M., “Rapid Vaporization of Kidney Stones, Ex Vivo, Using a Thulium Fiber Laser Operated at Pulse Rates up to 500 Hz Using a Stone Basket,” Selected Topics in Quantum Electronics, IEEE Journal of, vol.20, no.5, pp.1,4 Sept.-Oct. 2014
  7. ^ "Endoscopic pulsed-dye laser lithotripsy: 159 consecutive cases.". J Endourol. 8: 25–7. Feb 1994. doi:10.1089/end.1994.8.25. PMID 8186779. 
  8. ^ "Pulsed dye laser lithotripsy--currently applied to urologic and biliary calculi.". J Clin Laser Med Surg. 9: 355–9. Oct 1991. PMID 10150133. 
  9. ^ "Laser prostatectomy with the holmium: YAG laser". Tech Urol. 1: 217–21. Winter 1995. PMID 9118394. 
  10. ^ "Holmium:YAG lithotripsy yields smaller fragments than lithoclast, pulsed dye laser or electrohydraulic lithotripsy.". J Urol. 159: 17–23. Jan 1998. doi:10.1016/s0022-5347(01)63998-3. PMID 9400428. 
  11. ^ Wilson, C.R., Hardy, L.A, Irby, P.B., Fried, N.M., "Collateral damage to the ureter and Nitinol stone baskets during Thulium fiber laser lithotripsy," Lasers Surg. Med. (2015).
  12. ^ Wilson, C.R., Hutchens, T.C., Hardy, L.A, Irby, P.B., Fried, N.M., "A miniaturized, 1.9 french integrated optical fiber and stone basket for use in thulium fiber laser lithotripsy," J. Endourol. (2015).
  13. ^ Hardy, L.A; Wilson, C.R.; Irby, P.B.; Fried, N.M., “Rapid Vaporization of Kidney Stones, Ex Vivo, Using a Thulium Fiber Laser Operated at Pulse Rates up to 500 Hz Using a Stone Basket,” Selected Topics in Quantum Electronics, IEEE Journal of, vol.20, no.5, pp.1,4 Sept.-Oct. 2014
  14. ^ Hardy, L.A, Wilson, C.R., Irby, P.B., Fried, N.M., "Thulium fiber laser lithotripsy in an in vitro ureter model," J. Biomed. Opt. 19(12): 128001, 2014.
  15. ^ Blackmon, R.L., Hutchens, T.C., Hardy, L.A., Wilson, C.R., Irby, P.B., Fried, N.M., “Thulium fiber laser ablation of kidney stones using a 50-μm-core silica optical fiber,” Opt. Eng. 54(1): 011004, 2015.

See also[edit]