Cochlear Findings in VIIIth Nerve Tumors

Abstract

We have been particularly concerned with the large number of patients with confirmed retrocochlear lesions who have demonstrated cochlear test results on audiological evaluation. The literature is replete with information suggesting that the patient with a tumor of the VIIIth nerve will demonstrate the classical signs of significant reduction in auditory speech discrimination, abnormal tone decay, lack of loudness recruitment, negative SISI scored and Békésy tracings classifiable as either type III or type IV. We feel it is safe to say that one rarely encounters such a clearcut picture.

In this paper we discuss the audiologic data for a series of patients recently evaluated in our department. All these patients demonstrated only cochlear findings on audiological evaluation, yet all patients had surgically confirmed VIIIth nerve tumors.

Key Words:

• Békésy audiometry
• Difference limen for intensity
• Temporary threshold drift
• Loudness recruitment
• Conventional speech audiometry
• Speech-to-noise ratio