It is a clinical Dx
is a DX made by knowledgable clinician that takes a very careful history and physical exam. Test or consults needed to rule out anemia
, thyroid, sinus, dental, eye
problems, brain masses, neuralgias, food reax.
If no cause is found, then DX is primary migraine, in which all tests r negative. There are excellent treatments for migraine, so work w neuro till best rx or prevention found.