Test / Diagnosis

Because signs and symptoms of acoustic neuroma are likely to develop gradually and because hearing loss, tinnitus and dizziness can be indicators of other middle and inner ear problems, it may be difficult for your doctor to detect the tumor in its early stages. Acoustic neuromas often are found during screening for other conditions.

After asking questions about your symptoms, your doctor will conduct an ear exam and may request the following tests:

* Scans. Magnetic resonance imaging (MRI) or computerized tomography (CT) scans of your head can provide images that confirm the presence of an acoustic neuroma.
* Hearing test (audiometry). During this test conducted by a hearing specialist (audiologist), you wear earphones and hear sounds directed to one ear at a time. The audiologist presents a range of sounds of various tones and asks you to indicate each time you hear the sound. Each tone is repeated at faint levels to find out when you can barely hear. The audiologist will also present various words to determine your hearing ability.
* Electronystagmography (ENG). This test evaluates balance (vestibular) function by detecting abnormal rhythmic eye movement (nystagmus) often present with inner ear conditions. The test measures your involuntary eye movements while stressing your balance in various ways.
* Brainstem auditory evoked response (BAER). This test checks hearing and neurological functions. Electrodes on your scalp and earlobes capture your brain's responses to clicking noises you hear through earphones and record the responses on a graph.