The double-membrane break syndrome in sudden hearing loss.

Some patients with sudden hearing loss actually have two membrane breaks, one at the oval or round window and one further inside the cochlea. One may heal spontaneously and the other not, or both, or neither. It is very likely impossible to detect this early from the threshold audiogram, because the intracochlear breaks allows endolymph and perilymph mixing which spreads over much of the anatomically normal clchlea causing diffuse loss of function. This theory is illustrated by three case histories.