Electronystagmography (ENG) refers to a battery of tests used to evaluate the vestibular system. The tests include (1) the Dix-Hallpike test, (2) ocular motor tests, (3) a search for positional and/or spontaneous nystagmus, (4) the caloric test, and (5) the failure of fixation suppression test. During ENG testing, eye movement is measured to determine the presence of peripheral (vestibular nerve and/or end-organ) vestibular or central nervous system (CNS) dysfunction. Two methods for recording eye movement are electro-oculography (EOG) and video-nystagmography (VNG). EOG is a recording of the corneoretinal potential with surface electrodes placed on the face, whereas VNG measures eye movement through the use of infrared video cameras mounted in goggles worn by the patient during testing.