Of 54 patients with acoustic neuroma (AN) treated at our hospital from 1989 to 1995, 17cases showed the initial symptom of sudden hearing loss, and 11cases showed a so-called “valley type” pattern.
The bottom frequency of “valley type” audiogram of the patiants with AN was between 1 kHz and 2 kHz, and these patients showed a slight recovery in early stage comparing with patients with Sudden deafness.
These findings suggested that it is neccesary to make further audiological and radiological examinations to detect AN in patients with sudden hearing loss with a “valley type” audiogram.
