Hi, beancounter:
I'm sorry you have a reason to be here (a diagnosis of having an acoustic neuroma tumor) but glad you found us, as this is a very informative site and this forum consists of some very helpful people who know what you're experiencing.
If your AN is really small and you're asymptomatic at this point then 'watch and wait' (do nothing) is likely your best option. However, as your doctor will undoubtedly inform you, that requires at least an annual MRI scan (possibly semi-annual, depending on your doctor's advice) to watch for any growth of the AN tumor. Radiation treatment is a probably viable option for you - again, your physician will advise you, we can't - and is generally efficacious for most AN patients that undergo the treatment, which comes in various forms.
Trust me, we're all full of anxiety when first diagnosed. This is scary and something few people have to deal with. Unpleasant consequences can occur from surgery and/or radiation. Not always, but sometimes, and those seem to the ones you read about. My AN was relatively huge and had to be operated on quickly, with little time for much mental/emotional preparation but, even at my age (then 63) I pulled through just fine and recovered quickly. Today, you wouldn't know I ever had the tumor, surgery and five weeks of daily radiation treatments following. My symptoms disappeared, I've conquered lingering balance problems and fully adjusted to only hearing in one ear. Because you have no symptoms, you're fortunate. Your AN many never grow (it happens) or grow so slowly that you 'll have lots of time to prepare for treatment, be it radiation or surgery.
One thing I always mention to newly diagnosed patients: an acoustic neuroma is not malignant (cancerous) and it is very treatable.
You'll be fine and the anxiety will pass. Please stay in touch with this forum. We understand what you're going through and we care.
Jim