Well, I had my follow up appointment with the ENT. My hearing is stable, however it turns out to be low frequency loss (I had thought it was high frequency loss). The doctor wasn't as dismissive about the throbbing pains this time around, partly because it has persisted for 3 months and mostly because previously he thought it was on the other side. When I corrected him that it was on the side of my bad ear, he seemed to take it a bit more seriously. The worsening of the high pitched ringing tinnitus also got the wheels turning a bit.
He did another CT scan. If that is turns out normal, then he will refer me to a TMJ specialist. It that turns up negative, then he will evaluate the situation for possible MRI. He claims that the insurance companies will balk if the proper course of starting out simple isn't followed. I pressed about the ability of CT to rule out an acoustic neuroma and he agreed that MRI was the way to go, but we're not there yet. If the follow up after the TMJ doesn't prompt the MRI, then I plan to get a second opinion.
By the way, in my research I've read about nystagmus. Just yesterday, I noticed while on my computer that my eyes were twitching and the letters/words on the screen were darting back and forth very fast and lasted for about 15-20 seconds. That made me recall at least a dozen times within the past year or so that has happened while reading or on the computer. They seemed to be isolated and infrequent and therefore I don't know if that is normal in the population at large or another "symptom" to note. I didn't mention to the doctor simply because I just now made the connection. Does anyone have any insights to this infrequent twitching? It seems most cases that I have read about are very frequent and disruptive, therefore I'm reluctant to add this to my list.
Also, I've read conflicting research that low frequency hearing loss is either uncommon for AN or that it accounts for as much as 1/3 of AN's. Further, AN's that result in low frequency loss affect nerves that aren't affected by ABR stimulus. Therefore, my negative ABR could be explained by the low frequency loss (assuming I turn out to have one).
Anyways, I will have to wait for clarity and just hope that the ENT doesn't call me into the office regarding the CT result (that likely wouldn't be a good sign).