Hi, Jill ~
Although I'm sorry you had an acoustic neuroma to deal with, I'm glad you've found the ANA website/Discussion Board, decided to register and post your question.
First, congratulations on what seems to have been a very successful AN removal surgery, Middle Fossa style. Unfortunately, in some AN surgery patients, the 4th cranial nerve can be negatively impacted post-op. The good news is that, assuming the nerve was not damaged during surgery or by the growth of the now-removed tumor, your double vision should self-correct as the nerve 'settles down'. I wish I could put a timeframe on when that will occur, but no one really can, including your doctor. However, his defensiveness is unfortunate and indicates some insecurity on his part but frankly, there is really nothing you can do about that. Many AN surgery patients experience short-term double vision immediately post-op. I had a very successful surgery but experienced double vision for perhaps three days immediately following my surgery. It disappeared and never returned. I trust your vision will also return to normal, soon. The fact that your eyes are otherwise fully functional is very encouraging. I don't know if there are any specific exercises you can try to help resolve the double vision but if there are, I'm sure one or more of our knowledgeable members will be posting that, soon. Meanwhile, I hope you'll be a frequent 'visitor' to the ANA forums and share your progress with people who understand what you're dealing with and are totally supportive.
Jim