Pain and Burning Sensation on the scalp

My dad is 64 Years old and he has cervical spondylosis (between C1 and C2 vertebrae) from past almost 25 years.
He has burning sensation on scalp and sometimes numbness. If he goes out in sun for 5 minutes also the burning sensation on scalp will be severe. He has burning sensation in eyes. He cannot bear the tube light or cannot watch televison due to bright light. He cannot bear loud noises and cannot talk on phone for longer time. These will cause nerves weakness.  He had hearing tests done and doctors could not able to diagnose it.  Your help is greatly appreciated.