Hi. I'm online and happy to answer your question today.
That is an excellent question.
From what you have posted, his pain is most likely related to his TN. But, yes, a complete eye exam by an ophthalmologist would be able to easily rule out the presence of uveitis or other ocular condition.
Usually with severe uveitis, the patient has severe photophobia (sensitivity to light), decreased vision in the affected eye, an aching/boring type of eye pain and, sometimes, if the pressure is high, nausea and vomiting.
In my opinion it wouldn't hurt to have an eye doctor take a look at your husband just to be sure.
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