This CPB is revised to state that intrathecal baclofen is considered medically necessary for stiff person syndrome. This CPB is revised to state that intrathecal baclofen is considered experimental and investigational for neuromyotonia (Isaac's syndrome), hydrocephalus, and rheumatoid arthritis. This CPB is revised to state that intrathecal morphine is considered experimental and investigational as a treatment for gastroparesis.