Whole brain radiation

Hello, friends
I'd like to hear from anyone who has had whole brain radiation. My MRI this week found 15 small lesions which the radiological onc has assured me that he can "get rid of" with 25 sessions of whole brain rad. Today I got fitted for the mask which was a grueling ordeal since I have trouble breathing while laying flat. Of course the most life-threatening thing is the advance of tumors in the liver but my oncologist thinks it would be too hard on my blood counts to be in chemo and radiation at the same time so he has put me on fasodex (sp?) for the 6 weeks that I'll be in radiation.
So, anyone out there had the "whole brain" thing? Comments? I'm almost afraid to ask.
Carol (Photini)