Inoperable craniel avm/pain

hy husband has an inoperable avm, diagnosed since 1993. there has been no bleed that we know of, however, many seizures and hospitalization for a medically induced coma. since that episode, he has had mental/phycological issues. the pain in his head is tremendous what pain regimens or treatments have been administered to any one put there and what has worked. the pain and quality of life is not good. he also experienced hallcinations and unusual behavior after the coma. any comments.......thanks sue