Brief Answer:
From the symptoms, hearing tests and MRI + CT scanning.

Detailed Answer:
Hi,

Thank you for your query.

1. An Acoustic Neuroma is a rare benign tumour of the eight cranial nerve. It is usually suspected if there is a progressive unilateral hearing loss. Tinnitus, imbalance and fullness in the ear are also felt by the patient. Larger Acoustic Neuromas can give rise to headaches (raised intracranial tension) and other cranial nerve symptoms (facial and corneal numbness, facial weakness, decreased gag reflex, change in voice and so on).

2. A high resolution MRI + CT of the temporal bones with contrast will reveal the smallest of Acoustic Neuromas. A Pure Tone Audiometry (PTA) and other hearing tests are required.

3. Meniere's disease is far more common and diagnosed on the following criteria:
a. Vertigo
b. Fluctuating hearing loss
c. Tinnitus
d. Fullness in the ear
There is usually nausea and vomiting, the hearing usually worsens during an attack and the tinnitus also worsens. Hearing loss is initially more in lower frequencies. Meniere's Disease should normally respond to a salt restricted diet, acetazolamide (diamox) and betahistine (Vertin).

I hope that I have answered your queries. If you have any further questions, I will be available to answer them.

Regards.

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