Sher,
As part of the radio process (regardless of type of radio treatment), we are always mentally prepared that edema/swelling may occur. While the swelling may occur, it may cause pressure on the hearing nerve. Some experience temp decrease in hearing, some don't. Some may lose hearing (perm) post radio, some don't. I've heard from many in the same shoes.... myself included.
Approx 4 mos post CK, I had temp decrease in hearing. My hearing test at that time confirmed it... a 15db decrease. After that, it stabilized, the pressure stopped and my hearing resumed back to what it was at the time of treatment. I have been lucky on that account.
Hang in there... see if the doc recommends a short term course of anti-inflammatories (ie: Ibuprofen, steroids, etc). Please remember that you just had your CK less than a month ago and the post treat journey has started. There may be bumps along the way and you know what to look out for (not to actually look for them but you are aware of what may/could occur, although much does not occur for many). You know the average timeframes for things to possibly crop up. Don't keep "looking" for them but try to keep them in the back of your mind, but also knowing that you have educated yourself for these things that could/could not happen.
Hang tough!
Phyl
