Abstract: A light transmitting catheter includes a tube having a proximal end and a distal end. The tube contains aqueous fluid an interior surface on the tube has an index of refraction less than the index of refraction of water. The proximal end is provided with an adapter for receiving light from a light source associated with the proximal end of the tube and with an adapter for accepting an aqueous fluid to be passed throughout a substantial length of the tube for transmitting light to the distal end of the tube.