Improved laser energy delivery devices, providing greater transmission efficiency, longevity of use and safety are described. In one embodiment, a device for delivering laser energy includes a conventional optical fiber within a metal or plastic cannula provided with a laser energy emission window. A reflective material is disposed in a space between the distal end portion of a metal or plastic sheath and the optical fiber, as well as about any extension or endpiece of the distal end of the sheath. The reflective material reflects aberrant emissions of laser energy from the optical fiber as it erodes, and laser energy backscattered from the target tissue away from the distal end of the sheath back into the optical fiber or out of the distal end of the sheath, thereby preventing damage due to overheating. Other embodiments include devices that transmit laser energy more safely, efficiently and durably laterally from the axis of the optical fiber.