Hi, Ellen ~
I'm glad you discovered the ANA website, specifically, the discussion forums.
I'm sure you realize that no one can accurately predict what your husband's MRI will show but from the information you've offered, the chances of his having an acoustic neuroma are relatively good, although I hasten to add that there are other medical issues that can manifest similar problems (unilateral hearing loss, tinnitus, dizziness, headaches).
If the MRI indicates an acoustic neuroma is present, it will also show the size and configuration, both of which are critical in determining the treatment options. Basically, microscopic surgery or non-invasive radiation. Observation ('watch-and-wait') may be an option but with his symptoms, not one he is willing to try. Those are issues his doctor will discuss with you both and frankly, until the MRI results are known, it is a bit premature to discuss them in any detail.
Ironically, I was diagnosed with a large (4.5 cm) AN when I was the same age as your husband. Surgery was the only option. My tumor was 'debulked', it's blood supply severed and, 90 days later, radiated to destroy it's ability to re-grow. That was in June, 2006. Subsequent MRI scans showed tumor necrosis (cell death) and the beginnings of shrinkage. My surgery went near-perfectly and my recovery was relatively rapid. The radiation (FSR) was uneventful and successful. Unfortunately, my procrastination in seeing a doctor (sound familiar?) caused me to lose all hearing in the affected ear. I remain SSD (single side deaf) but have adjusted quite well, although it remains a mild impediment. Other than the irretrievable hearing loss, my pre-diagnosis symptoms never returned. Today, almost seven years later, I'm doing great.
One thing to keep in mind, if your husbands MRI shows an acoustic neuroma is present is that it is a benign tumor (99.9% of the time) that will not metastasize, meaning, it is non-cancerous - but still problematic. Frankly, most doctors will tell a patient with an acoustic neuroma that it is the 'best kind of brain tumor to have'.
I suggest that neither you nor your husband do too much speculation until he undergoes the MRI scan and you know what you're dealing with - if anything. Too much 'preparation' can generate unnecessary anxiety that neither one of you need right now. Of course, should the MRI indicate an acoustic neuroma is present, we're here to offer information and support, 24/7.
Jim
