Abstract: Laser radiation is coupled to an optical instrument having a relatively narrow working edge from which the radiation is emitted in a relatively narrow zone of intense radiation leakage. The working edge is placed in contact with vascularized tissues, and the laser radiation emanating from the working edge in combination with the contact between the working edge and the tissues forms an incision, and the laser radiation photocoagulates tissue adjacent the incision. The contact between the working edge and the tissues accurately positions the laser radiation with respect to the tissue, places pressure on vessels to aid hemostasis, mechanically stresses the incision line and provides the surgeon with tactile feedback. Radiation propagates from a laser to the optical instrument through a low-loss flexible fiberoptic waveguide by means of multimode optical waveguide propagation.

Abstract: A Photocoagulating scalpel system including a scalpel having a sharp, transparent blade for forming an incision, and a laser optically coupled to the blade for coagulating blood adjacent the incision. Laser radiation is transported to the blade through a low-loss fiberoptic waveguide. The radiation propagates through the waveguide and blade by means of multimode optical waveguide propagation wherein each mode has a discrete angle of incidence with respect to the blade surface. As the radiation reaches the beveled cutting edge of the blade, the angle of the blade surface changes causing the radiation to be emitted from the blade because the incident angles of individual modes fall below the critical internal reflection angle of the blade. Radiation leakage is further increased by the presence of blood on the blade surface which increases the critical internal reflection angle of the blade.