In vitro studies and computer simulations to assess the use of a diode laser (850 nm) for laser-induced thermotherapy (LITT).
OBJECTIVE
This study investigated the feasibility of 850 nm diode laser-induced thermotherapy (LITT), a new procedure providing local hyperthermia and photocoagulation, a minimally invasive treatment of tumors, and other disorders such as benign prostate hyperplasia.


METHODS
An improved fiber optic diffuser inserted through a catheter was used to irradiate prostate, liver, and kidney tissue in-vitro. Experimental results were compared with predictions from mathematical simulations based on measured optical tissue parameters.


RESULTS
After 10 minutes of irradiation with 2-4.6 W CW laser power, sizable coagulation diameters had been achieved. In prostate and kidney tissue, temperature rises and coagulation diameters after laser irradiation were found to be smaller than in liver tissue. Those tissues also had a higher threshold for carbonization, thus reducing the risk of damage to the delivery system.


CONCLUSIONS
The data suggest that a low power diode laser can be recommended for use in LITT to treat prostate and kidney tissue.
Prapavat
V
V
Institut für Medizinische/Technische Physik und Lasermedizin des Universitätsklinikum Benjamin Franklin, Berlin, Germany.
Roggan
A
A
Walter
J
J
Beuthan
J
J
Klingbeil
U
U
Müller
G
G
D000818:Animals; D001831:Body Temperature; D002244:Carbon; D002404:Catheterization / Q000295:instrumentation; D003198:Computer Simulation; D004285:Dogs; D005240:Feasibility Studies; D005336:Fiber Optic Technology / Q000295:instrumentation; D006358:Hot Temperature / Q000627:therapeutic use; D006979:Hyperthermia, Induced / Q000295:instrumentation / Q000379:methods*; D007668:Kidney / Q000473:pathology; D017075:Laser Coagulation; D053685:Laser Therapy; D008099:Liver / Q000473:pathology; D008297:Male; D019060:Minimally Invasive Surgical Procedures; D008954:Models, Biological; D009369:Neoplasms / Q000628:therapy; D055100:Optical Fibers; D011467:Prostate / Q000473:pathology; D011470:Prostatic Hyperplasia / Q000628:therapy; D013552:Swine
D002244:Carbon