In vitro investigation of endoscopic microsurgery with the laser diode (SONY 1W CW, 820nm) is described in this paper.
First, efficacy of carbon-coated fiber is examined. 400μm quartz fiber with carbon-coated end is prepared to introduce semiconductor laser power. With this fiber, contact irradiation to rabbits' femoral nerve, aorta, heart and goats' kidney is carried out under 830mW laser source. Each tissue can be vaporized in several seconds. Histologic observation shows heat degeneration layer with carbonized layer in each organ.
Next step, this laser fiber is introduced to endoscope, 1.7mm outer diameter. Under endoscopic observation, rabbit's left ventricle myocardium successfully vaporized.
For contact irradiation, metal-coated ceramic chip lower necessary power to vaporize tissue. With ceramic chip, however, energy loss and outer diameter increase at the connection. Then, we employ quartz fiber with carbon-coated end. Histologic observation shows little difference between ceramic chip and carbon-coated fiber.
With endoscope, the good aiming ability was demonstrated under several times magnification. As the next step, laser tissue welding under endoscopic observation is examined with this system. A compact endoscopic microsurgery system can be achieved with high power laser diode.
