I would wear your glasses... my hubby gets severe headaches even when his are dirty. That seems a lot less drastic and less painful than nerve injections.
Emg normal, MRI normal from 1 year ago and mar normal from 6 months ago. Headache might be coming from eye strain in left eye, my rx is -1.oo sphere and I don't where my glasses and left eye is blurry, when I where them left eye isn't blurry.
Did you get a copy of the reports, and the MRI and MRA? What did the doctor say? Did you have other tests on the nerves such as EMGs or NCVs?
Have they tried any medications like neurontin or the like? What kind of doctors are you seeing?
I assume you discussed your syptoms with the doctor(s) who ordered the MRI and MRA and they did not feel further evaluation of the brain was indicated?
Other problems which might cause pain in the area you described could be an ear problem, a dental issue, or TMJ. If you have not already done so, you might make appointments with a dentist and an ENT (ear, nose and throat) physician.
I don't think nerve injections are a good idea until it is determnied what is causing your symptoms.
Good luck with finding a cause, and hopefully a solution, for this problem.