Videosnystagmography (VNG) is a test of your balance or vestibular system. Your eye movements are the objective measure of dizziness, vertigo or imbalance. The test is performed with goggles that have infra-red cameras inside and magnify and record your eye movements during the test. The test is divided into three parts: 1 visual testing during which you will watch a target that moves either horizontally or vertically and in various patterns; 2 positional testing, in which you will be moved through several head and body positions ; and 3 caloric testing in which warm and cool air is applied to each ear for one minute. This application of air changes the temperature within the balance mechanism and creates an artificial sense of movement or dizziness which does not last more than one to two minutes. Patients are often concerned when they are told they will be made to feel dizzy; however, dizziness is a healthy response under these conditions and the sensations will fade quickly.
