Non-metallic VEP stimulator without interference in CT scanning for neurosurgical operation

Non-metallic flash-type stimulators for monitoring visual evoked potential, named as the Fiber-Eyes, are proposed. Conventional VEP stimulators are comprised of LEDs and the print circuits, i.e. metallic materials, inside the stimulator. Proposed Fiber-Eyes are made from plastic optical fibers, silicone rubber, and external light source. Thus the Fiber-Eyes can be used together with CT scanning without interference in the image due to not use of the metallic parts during neurosurgical operations. They do not also radiate heat because the flash light for stimulus is supplied through the fibers, and thus it can avoid desiccation of the bulbar conjunctiva of patient in the operation.