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Title: Segmental irradiation of the bladder with neodymium YAG laser irradiation

Abstract

The Neodymium YAG laser energy source can be readily adapted for cystoscopic use by some simple modifications of existing urologic equipment. Both the fiberoptic resectoscope and a deflecting cystourethroscope have been adapted for this purpose. Fixation of the fiber tip 1 cm. from the target and use of a divergent beam of 36 degrees allows the delivery of standardized dosage to a relatively large bladder tissue volume. Animal experiments involving 35 mongrel dogs established that repetitive overlapping doses of 200 joules ech can successfully treat a large area of bladder resulting in a full thickness bladder wall injury. This technique has been used in 4 high risk patients with infiltrating bladder cancer without adverse sequelae. The ability to reliably produce a full thickness lesion may give this modality a therapeutic advantage over conventional cautery techniques especially for the treatment of residual infiltrative carcinoma.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Department of Surgery (Urology), University of Alberta, Edmonton, Canada
OSTI Identifier:
6096530
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Urol.; (United States); Journal Volume: 128:5
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; BLADDER; LOCAL IRRADIATION; NEODYMIUM LASERS; PERFORMANCE; USES; NEOPLASMS; RADIOTHERAPY; COMPARATIVE EVALUATIONS; DOGS; NEODYMIUM; RADIATION DOSES; RADIOSENSITIVITY; THICKNESS; USA; ANIMALS; BODY; DIMENSIONS; DISEASES; DOSES; ELEMENTS; IRRADIATION; LASERS; MAMMALS; MEDICINE; METALS; NORTH AMERICA; NUCLEAR MEDICINE; ORGANS; RADIOLOGY; RARE EARTHS; SOLID STATE LASERS; THERAPY; URINARY TRACT; VERTEBRATES; 550603* - Medicine- External Radiation in Therapy- (1980-)

Citation Formats

McPhee, M.S., Mador, D.R., Tulip, J., Ritchie, B., Moore, R., and Lakey, W.H. Segmental irradiation of the bladder with neodymium YAG laser irradiation. United States: N. p., 1982. Web.
McPhee, M.S., Mador, D.R., Tulip, J., Ritchie, B., Moore, R., & Lakey, W.H. Segmental irradiation of the bladder with neodymium YAG laser irradiation. United States.
McPhee, M.S., Mador, D.R., Tulip, J., Ritchie, B., Moore, R., and Lakey, W.H. Mon . "Segmental irradiation of the bladder with neodymium YAG laser irradiation". United States. doi:.
@article{osti_6096530,
title = {Segmental irradiation of the bladder with neodymium YAG laser irradiation},
author = {McPhee, M.S. and Mador, D.R. and Tulip, J. and Ritchie, B. and Moore, R. and Lakey, W.H.},
abstractNote = {The Neodymium YAG laser energy source can be readily adapted for cystoscopic use by some simple modifications of existing urologic equipment. Both the fiberoptic resectoscope and a deflecting cystourethroscope have been adapted for this purpose. Fixation of the fiber tip 1 cm. from the target and use of a divergent beam of 36 degrees allows the delivery of standardized dosage to a relatively large bladder tissue volume. Animal experiments involving 35 mongrel dogs established that repetitive overlapping doses of 200 joules ech can successfully treat a large area of bladder resulting in a full thickness bladder wall injury. This technique has been used in 4 high risk patients with infiltrating bladder cancer without adverse sequelae. The ability to reliably produce a full thickness lesion may give this modality a therapeutic advantage over conventional cautery techniques especially for the treatment of residual infiltrative carcinoma.},
doi = {},
journal = {J. Urol.; (United States)},
number = ,
volume = 128:5,
place = {United States},
year = {Mon Nov 01 00:00:00 EST 1982},
month = {Mon Nov 01 00:00:00 EST 1982}
}
  • Application of lasers as cutting or coagulation instruments is based on the conversion of light energy into heat in the irradiated tissue. The extent and degree of the thermal action depends on the beam geometry and the energy of the incident light, as well as on the optic and thermal properties of this tissue. The extinction behavior in the tissue differs for the various laser systems employed in medicine. A comparison of the effects on bladder tissue of rats and rabbits is made with Neodymium-YAG laser and the argon and CO/sub 2/ lasers to demonstrate the advantages of the Neodymium-YAGmore » laser, especially for the therapeutic irradiation of bladder tumors.« less
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