Hi...
Ditto what all suggest... get an MRI... this i THINK is the only way to "rule out" an AN. That's why i got an MRI, unfortunately, it was ruled in!
Like Keepingup, i did not have contrast on my MRIs (maybe on the 3rd of the three i had, it was a different machine, but i can't really recall... i know i had dye for the CT scans before and after surgery).
In hindsight, my first presenting symptom of my AN was the ringing. I recall first becoming aware of it in 2001... on a quiet day looking out the window. I dont really remember it after that (either it was so mild, or it faded, or i adjusted) but by 2005, i remember googling the noise and calling it tinitus. I complained to my doctor about in late 2005 (was told it was a terrible thing, but nothing i could do).
I do not remember when i first became aware of the hearing loss (which grow worse over the years til i was dianosed in Jan 08). But i know several years ago (say 2004) i sense i was not hearing as well, and as it progressed I would tell friends about my "bad ear". I also remember walking down the street and finding that sirens (e.g. fire engines) really bothered me and made my head scream. I started covering both ears when one would pass me. By the time my AN was diagnosed, i was told i had lost about 25-30% of hearing (all at very high frequencies).
So that's my story, and everyone is differentn. An MRI is really no big deal so just do it. I am mildly claustrophobic, but i managed fine (relax, clothes your eyes, and it will over in no time).
Hope it is nothing, but best to find out for sure.
Good luck,
Trish