Laser lithotripsy is a

surgical procedure Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery s ...

to remove stones from urinary tract, i.e.,

kidney In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organ (anatomy), organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and rig ...

ureter The ureters are tubes composed of smooth muscle that transport urine from the kidneys to the urinary bladder. In an adult human, the ureters typically measure 20 to 30 centimeters in length and about 3 to 4 millimeters in diameter. They are lin ...

bladder The bladder () is a hollow organ in humans and other vertebrates that stores urine from the kidneys. In placental mammals, urine enters the bladder via the ureters and exits via the urethra during urination. In humans, the bladder is a distens ...

, or

urethra The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which Placentalia, placental mammals Urination, urinate and Ejaculation, ejaculate. The external urethral sphincter is a striated ...

History

Laser

lithotripsy Lithotripsy is a procedure involving the physical destruction of hardened masses like kidney stones, bezoars or gallstones, which may be done non-invasively. The term is derived from the Greek words meaning "breaking (or pulverizing) stones" ( lit ...

was invented at the Wellman Center for Photo medicine 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. Initially 504 nm dye lasers were used, then holmium lasers were studied in the 1990s.

Procedure

urologist Urology (from Greek οὖρον ''ouron'' "urine" and ''-logia'' "study of"), also known as genitourinary surgery, is the branch of medicine that focuses on surgical and medical diseases of the urinary system and the reproductive organs. Org ...

inserts a scope into the urinary tract to locate the stone. The scope may be a

cystoscope Cystoscopy is endoscopy of the urinary bladder via the urethra. It is carried out with a cystoscope. The urethra is the tube that carries urine from the bladder to the outside of the body. The cystoscope has lenses like a telescope or microscop ...

ureteroscope Ureteroscopy is an examination of the upper urinary tract, usually performed with a ureteroscope that is passed through the urethra and the bladder, and then directly into the ureter. The procedure is useful in the diagnosis and treatment of dis ...

, 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 collected in a "basket" and/or washed out of the

urinary tract The human urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressu ...

, along with the finer particulate "dust." The procedure is done under either

local Local may refer to: Geography and transportation * Local (train), a train serving local traffic demand * Local, Missouri, a community in the United States Arts, entertainment, and media * ''Local'' (comics), a limited series comic book by Bria ...

general anesthesia General anaesthesia (UK) or general anesthesia (US) is medically induced loss of consciousness that renders a patient unarousable even by painful stimuli. It is achieved through medications, which can be injected or inhaled, often with an analgesi ...

and is considered a

minimally-invasive procedure Minimally invasive procedures (also known as minimally invasive surgeries) encompass surgical techniques that limit the size of incisions needed, thereby reducing wound healing time, associated pain, and risk of infection. Surgery by definition ...

. It is widely available in most hospitals in the world.

Comparison

Laser lithotripsy (LL) has been evaluated against

extracorporeal shock wave lithotripsy Extracorporeal shockwave therapy (ESWT) is a treatment using powerful acoustic pulses which is mostly used to lithotripsy, treat kidney stones and in physical therapy and orthopedics. Medical uses The most common use of extracorporeal shock ...

(ESWL), finding both to be safe and effective. ESWL may be safer for small stones (<10 mm), but less effective for 10–20 mm stones. A 2013 meta-analysis found LL can treat larger stones (> 2 cm) with good stone-free and complication rates. Holmium laser lithotripsy had superior initial success and re-treatment rate compared to ESWL in a 2013 trial. The experimental thulium

fiber laser A fiber laser (or fibre laser in Commonwealth English) is a laser in which the active gain medium is an optical fiber doped with rare-earth elements such as erbium, ytterbium, neodymium, dysprosium, praseodymium, thulium and holmium. They ar ...

(TFL) is being studied as a potential alternative to the holmium:YAG (Ho:YAG) laser 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.

Lasers

Pulsed dye laser A dye laser is a laser that uses an organic dye as the lasing medium, usually as a liquid solution. Compared to gases and most solid state lasing media, a dye can usually be used for a much wider range of wavelengths, often spanning 50 to 100 na ...

s have been used with fiber diameters of 200–550 microns for lithotripsy of biliary and urinary stones. Ho: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. Holmium laser use results in smaller fragments than 320 or 365 micron pulsed dye lasers or electrohydraulic and mechanical methods. Thulium fiber lasers are being investigated.

References

{{Lasers Laser medicine Urologic procedures

History

Procedure

Comparison

Lasers

See also

References