JFT -
yes, with ANs there is a chance that you will lose your hearing and/or have facial nerve damage. Your inner ear contains not only your hearing nerve, but your facial and balance nerves as well. Losing 100% of your hearing is a given during Translab surgery, due to the approach because the docs open the inner ear. If you have some hearing, having retrosigmoid or mid fossa surgery might help you keep what hearing you have left.
I don't recall the exact percentages of facial nerve damage or loss of hearing, my doc gave them to me prior to my surgery, but that was almost 1 year ago.
Everyone's experience is different and a lot depends on the size and location of your AN, plus what the docs find when they go to remove the tumor. In my case, we had hoped to save my hearing, but my AN had grown and wrapped itself around my hearing nerve. In order to remove the entire AN, my hearing nerve was damaged leaving me SSD (single-side deaf). My facial nerve, however, was not damaged.
If you do end up completely deaf in your AN ear, there are options to help you hear again - specifically the BAHA and the TransEar. They won't enable you to hear exactly the way you used to, but they do help a lot.
Given the size of your AN, radiation (cyberknife aka CK or gamma knife aka GK) might be a possible treatment option for you. You might want to look into that and/or read some of the posts on this forum. In addition, if you haven't already, you should contact the ANA about brochures that explain ANs and their treatment. I found these materials invaluable.
Good luck in your AN journey. We're all here to help you, so feel free to ask us anything.
Jan