Chronic Headaches

[pk5956]

My nearly 11 year old son has now been suffering from headaches for over 4 weeks. On a scale of of 1 to 10, they are mostly around a 6 or 7 with spikes mostly in the mornings or evenings every other day to 9 or 10. The headaches are always in the same place, on the top of his head slightly to the right side. Its the size of a clementine and throbbing. The only trigger we have found is outdoor sunlight, but only when his headache is rising anyway. We have had a couple of days with only a 2 or a 3 headache where he played tennis or through a baseball with his friends. He has not been able to read ( which he loves) since this started.
He has had a bad sinus infection that is gone for over two weeks ( because of anti-biotics) and he went through a growth spurt prior to the onset. He grew 1 1/5 inches in 6 weeks after a period of slow growth. He eats like a wolf and sleeps for 8 to 10 hours after going to sleep with some trouble.
He has had a positive and negative sinus ct-scan as well as a regular ct-scan. He has had two MRI's with and without contrast fluids. He also had a spinal tab and took endless blood tests.
The outcome so far is that two heads of radiology found no physical reason for a headache. They noticed that his pituitary gland seemed to look a little lighter then usual but did not give that much importance.
The spinal tab was completely clear and the department of infectious diseases as well as the e&t department declared his headaches as not to come from anything falling under their domain.
He also had an examination with his dentist as well as his eye doctor who could not spot anything unusual.
He is being treated by the head of neurology with Prednisone (10mg) as well as Depakote (500m g), when the headaches spike we can also let him have Zomig (2,5) and Naproxen (375mg). When it gets to be unbearable he can have compozine  (Prochlorperazine Maleate 5mg).
None of the treatment have really helped him a lot. The compozine knocks him out, but sometimes the headaches return when the effect of the drug diminishes.
People have talked to us about anything from cranial massage to acupuncture and the consultation of a nutrionist.
Any advice?