CAUSES OF SENSORINEURAL HEARING LOSS The clinical pictures and causes of sensorineural hearing Joss are numerous and varied. Different causes often produce the same clinical profile, and a single cause may produce a variety of clinical pictures. In some cases of sensorineural hearing Joss, the cause is speculative or completely unknown. To complicate the problem further, physicians now are beginning to realize that in some patients with histories and audiologic findings highly suggestive of peripheral sensorineural impairment, the temporal bone findings at autopsy do not account for the hearing loss on the basis of any visible pathology. To provide the reader with a comprehensive perspective of sensorineural hearing loss, have included as many as possible of the characteristics of the conditions commonly

doi:10.1201/b21609-40

Chapter

CAUSES OF SENSORINEURAL HEARING LOSS The clinical pictures and causes of sensorineural hearing Joss are numerous and varied. Different causes often produce the same clinical profile, and a single cause may produce a variety of clinical pictures. In some cases of sensorineural hearing Joss, the cause is speculative or completely unknown. To complicate the problem further, physicians now are beginning to realize that in some patients with histories and audiologic findings highly suggestive of peripheral sensorineural impairment, the temporal bone findings at autopsy do not account for the hearing loss on the basis of any visible pathology. To provide the reader with a comprehensive perspective of sensorineural hearing loss, have included as many as possible of the characteristics of the conditions commonly

ABSTRACT

The most common cause of sensorineural hearing loss is presbycusis, the gradual reduction in hearing with advancing age. The hearing loss takes place in a well-defined manner. It occurs gradually over a period of years, usually with the very highest frequencies affected first and the lower ones gradually following. Both ears are affected at about the same rate, but sometimes the loss in one ear may progress faster than the other. Whenever an older patient is encountered who has a hearing loss much greater in one ear than in the other, a diagnosis of presbycusis should not be made without reservation, for it is likely that some other cause is also present.