OK, I'm going to get this out there in the hope that it jinxes it from actually happening! (False hope? Fuck it...)
In a show that's all about neurosurgery doesn't hallucinating seem like a set up for him to have a brain tumor? Or at the minimum get checked out for one?
In the book, one of the doctors does develop a brain tumor. It is NOT Ty. (I won't say who it is, because if it does happen in the show as it does in the book, it'd be spoilery to say the least.) Obviously, they could tweak the plotlines and give it to Ty instead but FOR CHRISSAKES, SHOW, NO. JUST NO. ;)