Hi SUNFLOWER!
Well, you needn't panic for sure. ANs are generally the slowest growing of benign brain tumors, comprising 6% of all brain tumors. Growth rates, if growing, may be about 1 - 2 mm. per year.
It's a good thing you have another MRI scheduled as MRI has an inherrant factor of + or - 1 - 2 mm. in tumor size and exact location.
Would like to read the results of that MRI re: Tumor size and location.
Can you still hear ok and have good balance?
In some cases of AN, careful watching and waiting is preferred over treatment depending on size and location and whether the AN tumor is growing or not.
Treatment options include 3 basic forms of microscopic neurosurgery or a couple different forms of radiation.
Keep reading some posts here and notice the 'search' box at the top. Spend time at the ANA's home page
http://www.anausa.org/ or http:www.hei.org/ ( House Ear Institute ) in LA. Maybe even
http://www.irsa.org/ It's good to choose a treatment provider who does a lot of AN treatments in a year. Say, at least 1 or 2 a week minimally and possibly get a couple opinions by 2 neurosurgeons and 2 radio-oncologists ( not that this is malignant ). You can receive other opinions by having your MRI sent to various institutions. HEI being 'prime' and a free telephone consult from Drs Brackmann or Friedman.
Don't be frightened at surgical reports you might see on the web at http:///www.anarchives.org/ The editor employs scare tactics in their anti-surgical and pro-radiation bias.
Best wishes. Please feel free to post anytime with any question.
Russ