Help

My managed care group gave me a modified approval for RNY surgery. I requested to go outside my managed care group for surgery because the surgeon with my group said basically it's either the band or nothing. So if my group does offere RNY and I want that surgery how do I appeal the surgeon's decision. After reading the correspondences and calling PacifiCare it's sound so promising that they will approve the RNY, but my issues are with the managed care group. Please advise!