Experimental use of semiconductor diode laser for neuroendoscopic surgery

The authors demonstrate an experimental use of the newly developed high power aluminium-gallium-arsenide (AlGaAr) diode laser (DIOMED 25, Olympus Optical Company, Tokyo, Japan). The unit consists of a compact body and fiberoptic probes with small accessories. There are two types (contact and non-contact) of probes. Tissue effects on rat liver, femoral artery, and brain tissue were examined. Adding that, we measured the thermal changes on the liver surface produced by the laser beam with a thermography system. For coagulation with the contact probe, 5 or 7 W was adequate but 10 W was too excess because of tissue adhesion. For cutting, low absorption of the laser in less vascularized tissue like brain white matter provided a deeper tissue damage compared with more vascularized tissue. The temperature at the center reached over 100 degrees C during 10 seconds after laser treatment with the cutting probe. These findings suggest that this system proved to be a good candidate for endoscopic hemostasis and cutting with meticulous maneuver.