A liquid core laser optical scope for illuminating, viewing, and delivering laser energy to a site in a lumen of an animal or human body which includes a flexible tube for insertion into the lumen, a conduit housed within the tube, a fluid source for coupling a flow of light transmissive liquid into...http://www.google.ca/patents/US5573531?utm_source=gb-gplus-sharePatent US5573531 - Fluid core laser angioscope
