This article is from the Tinnitus FAQ, by firstname.lastname@example.org (Mark Bixby) with numerous contributions by others.
First was a hearing test. This was followed by an MRI to ensure
there wasn't a tumor to deal with. There was also the physical to
ensure there was no other underlying cause, including Diabetes.
Then being referred to a surgeon who specializes in this kind of
thing. He did further hearing tests and another test which I will
have to get the name for you. It consists of lights on the wall
that you follow with your eyes. They also insert warm and cold
water into each ear (ENG/AU test) to measure the response; a
short vertigo spell is the result for healthy ears. There is also
a special set of hearing tests that they do.