Intracorporeal Lithotripsy
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Endoscopic lithotripsy refers to the visualization of a calculus in the urinary tract and the simultaneous application of energy to fragment the stone or stones into either extractable or passable pieces.
Many calculi in the upper urinary tract are treated with extracorporeal shockwave lithotripsy (ESWL). However, for stones that are poor candidates for this modality, endoscopic therapy is indicated. Ureteroscopy is the most common means of visualizing an upper urinary tract calculus. In addition, percutaneous techniques (eg, percutaneous endourology) can also be used.
Depending on stone size and location and associated ureteral obstruction, various treatments can be used. Most ureteral stones are small (< 5 mm) and should pass spontaneously without surgical intervention. Larger stones (< 1.5 cm) that are not associated with complete ureteral or renal obstruction can frequently be treated with ESWL in a noninvasive manner.
Endoscopic treatment is most commonly used to manage obstructive and/or large stones. Most infectious calculi are large and are usually located in the kidney. Thus, these are also commonly treated with endoscopy. In these scenarios, retrograde ureteroscopic lithotripsy or percutaneous nephrostolithotomy is used.
This article reviews the available endoscopic lithotrites and their clinical applications.
Endoscopic lithotrites include ultrasonic, electrohydraulic (EHL), and mechanical devices, as well as various lasers. These instruments are passed through the working channel of the endoscope to fragment stones into extractable pieces. Baskets and graspers are used during lithotripsy to immobilize stones and to remove stone fragments.
Ultrasonic lithotripsy was used initially. This modality requires a rigid endoscope and is commonly used via a percutaneous renal approach. It is less useful with ureteroscopy.
EHL probes deliver energy via 2 coaxial electrodes. Ignition creates a small spark of high temperature that vaporizes a small volume of water into a gaseous bubble. The bubble expands circumferentially. Power is proportional to the diameter of the probe. Drawbacks of EHL lithotripsy include its potential for damaging adjacent tissue, producing large fragments, and occasionally failing to fragment the hardest calculi, including calcium oxalate monohydrate.
Pneumatic mechanical devices, such as the Lithoclast, are small endoscopic jackhammers that work best when passed through a straight endoscopic working channel. With reusable stainless steel probes, the Lithoclast can be used through rigid or semirigid endoscopes. The Lithoclast is an efficient and economical means of fragmenting calculi and is particularly useful for managing large and hard stones. It is commonly used for large renal stones (percutaneously) and distal ureteral stones (ureteroscopically).
Laser lithotripsy was first introduced commercially in the late 1980s with the pulsed-dye laser, which uses 504 nm of light delivered through optical quartz fibers. This was a nonthermal safe laser that produced plasma between the tip of the fiber and the calculus, fragmenting stone with a photo-acoustic effect. The small flexible probes complemented both the semirigid and flexible ureteroscopes and could fragment most urinary calculi, excluding cystine. However, this was not a solid-state laser, and it required frequent maintenance, including changing of the coumarin dye. The energy available at the tip of the fiber is proportional to the fiber diameter. The 200-µm fiber allows the most endoscopic deflection but can deliver only 80 mJ of energy, which is frequently insufficient to fragment calcium oxalate monohydrate calculi.
Advancing laser technology has led to the development of the holmium:YAG (yttrium-aluminum-garnet) laser, which is a thermal laser that uses a 2150-nm wavelength of light. The energy is delivered in a pulsatile fashion through low–water-density quartz fibers. Johnson studied the soft-tissue effects of this laser and found that the thermal effect of this laser within a water-based medium was confined owing to a vaporization bubble formed at the tip of the fiber. [1] In 1995, Matsuoka et al presented the first clinical series of endoscopic lithotripsy with this wavelength and found it to be safe and efficient in treating ureteral stones. [2] As opposed to the coumarin pulsed-dye laser, holmium laser lithotripsy produces smaller fragments that can be, in part, irrigated from the collecting system during treatment.
The energy available at the tip of the holmium laser does not depend on the diameter of the fiber. Techniques used to increase treatment efficiency by varying fiber diameters with complementary endoscopes have been described. These techniques involve larger fibers complemented by increased stiffness, which decrease the flexibility of the endoscope.
For additional information, see Medscape Reference’s Lasers in Urology article.
Ureteroscopic lithotripsy as a common treatment for distal ureteral stones began in the early 1980s. During the same period, ESWL was introduced as a treatment for uncomplicated, moderately sized renal calculi.
While ureteroscopy progressed over the next 10 years, extracorporeal shockwave lithotriptors evolved to second-generation and third-generation devices that required fewer anesthetics during treatment but yielded lower stone-free rates and more related procedures than the first-generation machines.
New generators with smaller focal zones had focused shockwaves and required lower overall power.
The imaging on the newer extracorporeal lithotriptors allowed easier localization of ureteral stones, and there was great enthusiasm for treating stones throughout the entire upper urinary tract with this modality.
In certain cases, ureteral stents were also placed to localize stones in the ureter prior to shockwave lithotripsy and to ensure drainage of an obstructed upper urinary tract.
The newest devices did not obtain the success rates of the first-generation Dornier HM3.
In the early 1990s, the American Urological Association (AUA) developed guidelines for treating calculi. The guidelines were based on published clinical experience with ESWL and endoscopic lithotripsy.
The first guidelines panel dealt with the treatment of large renal stones (>2.5 cm). In this study, the AUA panel suggested that percutaneous nephrostolithotomy was superior to shockwave lithotripsy for such stones.
The second guidelines panel addressed the treatment of ureteral calculi. Treatment was stratified by stone size and location and other considerations. The panel suggested that stones smaller than 5 mm that are unassociated with high-grade upper urinary tract obstruction frequently pass without surgical intervention. The panel also suggested that patients with such stones but without prolonged, symptomatic, or complete upper urinary tract obstruction or associated infection should be monitored clinically.
The AUA panel recommended that larger ureteral calculi and those associated with significant obstruction can be treated with either ESWL or ureteroscopic lithotripsy. The most recent clinical series have found shockwave lithotripsy based on the newest extracorporeal lithotriptors to be less invasive and less efficient in treating ureteral stones, with fragment clearance often requiring as many as 4 months of follow-up.
Ureteroscopic treatment of renal calculi is gaining popularity because of the recognition of limitations of ESWL. Although ESWL is associated with minimal morbidity, its effectiveness is decreased in the treatment of certain stone compositions (eg, calcium oxalate monohydrate, cysteine), large stones, and stones located in the lower pole.
Flexible ureteroscopy with holmium laser lithotripsy is an attractive alternative to shockwave lithotripsy in the management of renal calculi in anomalous and/or ectopic kidneys (ie, horseshoe kidneys). In addition, ureteroscopy is a primary treatment in select patients with symptomatic stones in pelvic kidneys.
Certain patients or stone characteristics may favor ureteroscopic lithotripsy over ESWL or percutaneous nephrolithotripsy (PCNL). These include the following:
Lower-pole stone location
Cysteine or calcium oxalate monohydrate stone composition
Morbid obesity
Uncorrectable bleeding diathesis
Stones within a calyceal diverticulum or infundibular stenosis
Ectopic kidney
No contraindications to endoscopic lithotripsy exist, with the exception of those associated with endoscopy.
Johnson DE, Cromeens DM, Price RE. Use of the holmium:YAG laser in urology. Lasers Surg Med. 1992. 12(4):353-63. [Medline].
Matsuoka K, Iida S, Nakanami M, et al. Holmium: yttrium-aluminum-garnet laser for endoscopic lithotripsy. Urology. 1995 Jun. 45(6):947-52. [Medline].
Scotland KB, Kroczak T, Pace KT, Chew BH. Stone technology: intracorporeal lithotripters. World J Urol. 2017 Sep. 35 (9):1347-1351. [Medline].
Chen L, Sha ML, Li D, Zhuo J, Jiang CY, Zhu YP, et al. Treatment for residual stones using flexible ureteroscopy and holmium laser lithotripsy after the management of complex calculi with single-tract percutaneous nephrolithotomy. Lasers Med Sci. 2017 Apr. 32 (3):649-654. [Medline].
Dubosq F, Pasqui F, Girard F, et al. Endoscopic lithotripsy and the FREDDY laser: initial experience. J Endourol. 2006 May. 20(5):296-9. [Medline].
Kang HW, Lee H, Teichman JM, et al. Comparison of erbium:YAG versus holmium:YAG lithotripsy. J Urol. 2006. 175 (Suppl 4):574.
Marks AJ, Teichman JM. Lasers in clinical urology: state of the art and new horizons. World J Urol. 2007 Jun. 25(3):227-33. [Medline].
Grasso M, Conlin M, Bagley D. Retrograde ureteropyeloscopic treatment of 2 cm. or greater upper urinary tract and minor Staghorn calculi. J Urol. 1998 Aug. 160(2):346-51. [Medline].
Cohen J, Cohen S, Grasso M. Ureteropyeloscopic treatment of large, complex intrarenal and proximal ureteral calculi. BJU Int. 2013 Mar. 111(3 Pt B):E127-31. [Medline].
Alken P. Intracorporeal lithotripsy. Urolithiasis. 2018 Feb. 46 (1):19-29. [Medline].
Auge BK, Sekula JJ, Springhart WP, et al. In vitro comparison of fragmentation efficiency of flexible pneumatic lithotripsy using 2 flexible ureteroscopes. J Urol. 2004 Sep. 172(3):967-70. [Medline].
Beaghler M, Poon M, Ruckle H, et al. Complications employing the holmium:YAG laser. J Endourol. 1998 Dec. 12(6):533-5. [Medline].
Beiko DT, Denstedt JD. Advances in ureterorenoscopy. Urol Clin North Am. 2007 Aug. 34(3):397-408. [Medline].
Bierkens AF, Hendrikx AJ, De La Rosette JJ, et al. Treatment of mid- and lower ureteric calculi: extracorporeal shock-wave lithotripsy vs laser ureteroscopy. A comparison of costs, morbidity and effectiveness. Br J Urol. 1998 Jan. 81(1):31-5. [Medline].
Busby JE, Low RK. Ureteroscopic treatment of renal calculi. Urol Clin North Am. 2004 Feb. 31(1):89-98. [Medline].
Chaussy C, Fuchs G, Kahn R, et al. Transurethral ultrasonic ureterolithotripsy using a solid-wire probe. Urology. 1987 May. 29(5):531-2. [Medline].
Denstedt JD, Clayman RV. Electrohydraulic lithotripsy of renal and ureteral calculi. J Urol. 1990 Jan. 143(1):13-7. [Medline].
Denstedt JD, Eberwein PM, Singh RR. The Swiss Lithoclast: a new device for intracorporeal lithotripsy. J Urol. 1992 Sep. 148(3 Pt 2):1088-90. [Medline].
Dretler SP, Watson G, Parrish JA, et al. Pulsed dye laser fragmentation of ureteral calculi: initial clinical experience. J Urol. 1987 Mar. 137(3):386-9. [Medline].
Elbahnasy AM, Shalhav AL, Hoenig DM, et al. Lower caliceal stone clearance after shock wave lithotripsy or ureteroscopy: the impact of lower pole radiographic anatomy. J Urol. 1998 Mar. 159(3):676-82. [Medline].
Erhard MJ, Bagley DH. Urologic applications of the holmium laser: preliminary experience. J Endourol. 1995 Oct. 9(5):383-6. [Medline].
Fabrizio MD, Behari A, Bagley DH. Ureteroscopic management of intrarenal calculi. J Urol. 1998 Apr. 159(4):1139-43. [Medline].
Goodfriend R. Disintegration of ureteral calculi by ultrasound. Urology. 1973 Mar. 1(3):260-3. [Medline].
Grasso M. Experience with the holmium laser as an endoscopic lithotrite. Urology. 1996 Aug. 48(2):199-206. [Medline].
Grasso M. Ureteropyeloscopic treatment of ureteral and intrarenal calculi. Urol Clin North Am. 2000 Nov. 27(4):623-31. [Medline].
Grasso M, Beaghler M, Loisides P. The case for primary endoscopic management of upper urinary tract calculi: II. Cost and outcome assessment of 112 primary ureteral calculi. Urology. 1995 Mar. 45(3):372-6. [Medline].
Grasso M, Ficazzola M. Retrograde ureteropyeloscopy for lower pole caliceal calculi. J Urol. 1999 Dec. 162(6):1904-8. [Medline].
Grasso M, Loisides P, Beaghler M, et al. The case for primary endoscopic management of upper urinary tract calculi: I. A critical review of 121 extracorporeal shock-wave lithotripsy failures. Urology. 1995 Mar. 45(3):363-71. [Medline].
Hofbauer J, Hobarth K, Marberger M. Lithoclast: new and inexpensive mode of intracorporeal lithotripsy. J Endourol. 1992. 6:429.
Jeon SS, Hyun JH, Lee KS. A comparison of holmium:YAG laser with Lithoclast lithotripsy in ureteral calculi fragmentation. Int J Urol. 2005 Jun. 12(6):544-7. [Medline].
Knudsen BE, Glickman RD, Stallman KJ, et al. Performance and safety of holmium: YAG laser optical fibers. J Endourol. 2005 Nov. 19(9):1092-7. [Medline].
Leveillee RJ, Lobik L. Intracorporeal lithotripsy: which modality is best?. Curr Opin Urol. 2003 May. 13(3):249-53. [Medline].
Raney AM. Electrohydraulic lithotripsy: experimental study and case reports with the stone disintegrator. J Urol. 1975 Mar. 113(3):345-7. [Medline].
Weizer AZ, Springhart WP, Ekeruo WO, et al. Ureteroscopic management of renal calculi in anomalous kidneys. Urology. 2005 Feb. 65(2):265-9. [Medline].
Michael Grasso, III, MD Professor and Vice Chairman, Department of Urology, New York Medical College; Director, Living Related Kidney Transplantation, Westchester Medical Center; Director of Endourology, Lenox Hill Hospital
Michael Grasso, III, MD is a member of the following medical societies: American Medical Association, American Urological Association, Endourological Society, International Society of Urology, Medical Society of the State of New York, National Kidney Foundation, Society of Laparoendoscopic Surgeons
Disclosure: Received consulting fee from Karl Storz Endoscopy for consulting.
Andrew Ira Fishman, MD Assistant Professor, Department of Urology, New York Medical College
Andrew Ira Fishman, MD is a member of the following medical societies: American Medical Association, American Urological Association
Disclosure: Nothing to disclose.
Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference
Disclosure: Received salary from Medscape for employment. for: Medscape.
Bradley Fields Schwartz, DO, FACS Professor of Urology, Director, Center for Laparoscopy and Endourology, Department of Surgery, Southern Illinois University School of Medicine
Bradley Fields Schwartz, DO, FACS is a member of the following medical societies: American College of Surgeons, American Urological Association, Association of Military Osteopathic Physicians and Surgeons, Endourological Society, Society of Laparoendoscopic Surgeons, Society of University Urologists
Disclosure: Serve(d) as a speaker or a member of a speakers bureau for: Cook Medical; Olympus.
Erik T Goluboff, MD Professor, Department of Urology, College of Physicians and Surgeons, Columbia University College of Physicians and Surgeons; Director of Urology, Allen Pavilion, New York Presbyterian Hospital
Erik T Goluboff, MD is a member of the following medical societies: Alpha Omega Alpha, American Medical Association, American Urological Association, Medical Society of the State of New York, New York Academy of Medicine, Phi Beta Kappa, Society for Basic Urologic Research
Disclosure: Nothing to disclose.
Keith T Tracy, MD Resident Physician, Department of Urology, New York Medical College, Westchester Medical Center
Keith T Tracy, MD is a member of the following medical societies: Alpha Omega Alpha, American Medical Association, and American Urological Association
Disclosure: Nothing to disclose.
Acknowledgments
Medscape Reference thanks Dennis G Lusaya, MD, Associate Professor II, Department of Surgery (Urology), University of Santo Tomas; Head of Urology Unit, Benavides Cancer Institute, University of Santo Tomas Hospital; Chief of Urologic Oncology, St Luke’s Medical Center Global City, Philippines, for the video contribution to this article.
Medscape Reference also thanks Edgar V Lerma, MD, FACP, FASN, FAHA, Clinical Associate Professor of Medicine, Section of Nephrology, Department of Medicine, University of Illinois at Chicago College of Medicine; Research Director, Internal Medicine Training Program, Advocate Christ Medical Center; Consulting Staff, Associates in Nephrology, SC, for his assistance with the video contribution to this article.
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