Acoustic Neurinoma Presenting as Sudden Hearing Loss with "Valley Type" Audiograms.

It is well known that some patients with acousic neurinoma present with sudden hearing loss as a symptom. However, audiograms specific for acoustic neurinoma have not yet described.In our institutes, 12 out of 34 patients with acoustic neurinoma had sudden hearing loss as their chief complaint. Four of these 12 had audiograms indicating sensory neural hearing loss with “valley type” patterns.We describe these four patients and urge that any patient with sudden hearing loss who has a “valley type” audiogram be evaluated for possible acoustic neurinoma.