ENG ( Electronystagmogram ) is highly sophisticated computerized outdoor diagnostic procedure to examine a patient of vertigo or giddiness in order to locate the cause and site of disease. It is an electrical recording of nystagmus. got induced during the procedure. It is capable of detecting minute nystagmus even with eyes closed or in darkness. A record of spontaneous and positional nystagmus is made followed by recording the nystagmus induced by caloric test and rotational test.