gamma knife surgery for relief of bone metatasis pain

My husband has Stage IV prostate cancer and in the last 2 months has been in severe pain from bone metatasis.  He has been in the hospital twice for pain management.  He started taking 2mg of dilaudid every 4 to 6 hours and progessed to a 350 fentenal patch and 36mg dilaudid every 2 hours round the clock which did not offer complete relief and had terrible side effects.  He was admitted to the hospital to have a pick line put in and during that stay a pain management doctor introduced him to a neuro surgeon who told my husband about gamma knife surgery to his pituitary gland for pain relief of bone metatasis.  We had never heard of this procedure, nor had his oncologist or any other medical professionals we spoke to about it.  After my daughter found an article about it online and further discussion with the neuro surgeon he decided to have the procedure done. He had the surgery Monday Nov. 23 and had pain relief the very next day. He was feeling well enough to join the family at the table for Thanksgiving dinner and is now in the process of having his IV dilaudid reduced gradually to avoid withdrawal symptoms. We have never had a Thanksgiving with more to be thankful for. He is still very ill from his cancer but to have him relieved of his terrible pain has been a miracle for us. I wanted to know if anyone else had heard of this procedure.  It is done as ambulatory surgery and requires only one treatment. jane