Gusher is a very rare phenomenon, generally associated with congenital stapes fixation or otosclerosis in adult age, that may present during stapedectomy. A sudden perilymph flow occurs following platinotomy, due to congenital malformation (abnormally wide cochlear aqueduct or internal auditory canal fistula), that causes an abnormal connection between subarachnoid and perilymphatic spaces. This report deals with a case of bilateral gusher, occurring during stapedectomy, caused by an osseous fistula between bottom of internal auditory canal and the osseous labyrinth later observed at computed tomography scan. The usefulness of a radiologic examination is stressed for a correct therapeutic approach in the even contralateral ear stapedectomy.