Have you looked into trigeminal nerve issues? Perhaps you need something to combat that? I had my ENT numb me temporarily once (but it was just a temporary thing) as it effected my eye but you can use medications (neurontin, topamax etc) or even botox to reduce to pain. The meds have side effects so you have to weigh the benes vs drawbacks but I would see a neurologist if the ENT is running out of options.