High-powered CO2 laser cystoscope for endoscopic bladder surgery.
OBJECTIVE
The CO2 laser is potentially useful for the surgical treatment of superficial bladder tumors. High water absorption of the CO2 laser beam and the lack of a flexible fiber delivery system has hindered development of cystoscopes designed to evaporate bladder tumors. This report describes a cystoscope capable of delivering a high-power CO2 laser beam to all parts of the urinary bladder.


METHODS
A rigid 24 Fr. cystoscope transmitting 80 Watts of power via an articulated arm and infrared waveguide was built. Beam manipulation is by reflection using a movable mirror. Smoke and urine are evacuated by continuous flow of CO2 purge gas. An isotopic laser delivering an 11.1 micron wavelength beam prevents resonant absorption. Conventional 30-70 degrees telescopes are used. Scope performance and lesion morphology were tested in four female pigs.


RESULTS
A total of 80-85% of the incident energy is delivered to the mucosa. All areas of the bladder mucosa can be evaporated. All components tolerate wetting. Mucosa and lamina propria are evaporated with 30 Joules of delivered energy. Perforation occurs after 120-160 Joules are delivered to a single spot.


CONCLUSIONS
The limitations of power, beam transmission, beam manipulation within a small cavity, and resistance to wetting have been overcome.
Fournier
G R
GR
Division of Urology, Crawford Long Hospital, Emory University, Atlanta, Georgia 30308, USA.
Kung
A H
AH
Trost
D
D
D000042:Absorption; D000818:Animals; D002245:Carbon Dioxide / Q000008:administration & dosage; D020684:Cystoscopes; D003558:Cystoscopy / Q000009:adverse effects / Q000379:methods; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D007259:Infrared Rays; D007327:Insufflation; D053685:Laser Therapy / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D009092:Mucous Membrane / Q000601:surgery; D012906:Smoke; D013552:Swine; D001743:Urinary Bladder / Q000473:pathology / Q000601:surgery*; D001749:Urinary Bladder Neoplasms / Q000601:surgery; D014556:Urine; D014835:Volatilization; D014867:Water
D012906:Smoke; D014867:Water; D002245:Carbon Dioxide