Hi, rjo:
Sorry to hear about your balance problems. I know what it's like to have vertigo; certainly no picnic. I hope you feel better soon.
At the risk of unwarranted skepticism on my part due to having incomplete information, I'm going to go out on a limb and propose that you may not have Meniere's. I do not know of any cases of radiation treatment causing Meniere's disease and I suspect your ENT may have been "throwing darts in the dark."
I'm wondering if you had an "ecog" (electrococheography) test to diagnose Meniere's. This test is somewhat inconclusive yet the most relied upon for determining Meniere's. The ecog test determines if there is fluid in your inner ear, a condition known as hydrops. You cannot have Meniere's without having hydrops, although the reverse isn't necessarily true.
Unless hydrops has been established as fact in your case, it is pure conjecture to say you have Meniere's disease. Please don't get me wrong; I do not doubt that you have vertigo and all the other symptoms you've mentioned. It is unusual, but not unheard of, to develop vertigo after radiation treatments if you did not have vertigo before getting treated. But here you are, clearly suffering from vertigo. That I am not disputing. My point is that unless you've had an ecog test confirming Meniere's, you shouldn't worry about Meniere's too much. You may simply be suffering from swelling or internal inflammation of the treated tumor (a common occurrence after radiation treatments), which can cause balance problems but is almost always transitory.
You say your "hearing went." Did you lose all hearing on your AN side? If not, did you lose mostly low frequencies or mostly high frequencies? If you lost mostly high frequencies but low frequencies were largely preserved, then you do not have Meniere's disease, as Meniere's only affects low frequencies. Meniere's typically also presents as progressive hearing loss (often with subsequent partial rebound in hearing in between episodes) and not complete loss in one episode.
Please forgive my dubiousness if indeed you've had an ecog confirming hydrops and your hearing loss was centered on low frequencies. That would indeed point toward Meniere's. But if those two points don't ring true, then my hope is that I can give you some peace of mind and you won't automatically assume you have Meniere's, which is very difficult to treat (although it can be managed). My goal in replying to your post is to help you understand what's going on with your balance issues and reassure you that the cause may not be Meniere's but something much more transient in nature and less chronic of a condition. Also, if you don't have Meniere's, taking a diuretic may actually aggravate your balance issues, as it can dehydrate you. The dehydrating effects of alcohol, caffeine and chocolate, for example, are known to sometimes aggravate balance issues in people with ANs.
Hopefully I've armed you with some information that will help you understand what's causing your vertigo and help you to manage it the best way possible.
Best wishes,
TW
