Electronystagmography is the basic test for evaluating the functioning of the balance system. It is the primary test of balance function and is mandatory in all patients suffering from vertigo and imbalance, i.e. giddiness and instability. It is quite a time consuming and a little cumbersome test and though objective, yet it requires a lot of cooperation from the patient. ENG test evaluates the functional and structural integrity of the vestibular labyrinths and that of the vestibulo-ocular reflex system.