Thanks so much for your responses. I feel awkwardly selfish, asking what it might NOT be in an environment where folks obviously are dealing with the actual effects. Interestingly, the margarita is a great idea -- alcohol actually decreases the high frequency pitch in my ear.
Although my symptoms seem consistent with AN, I realize it could be quite a few things -- but the ENT went straight for the AN possibility while leaving everything else aside. I realize AN is rare, but then why not: "hey, let's treat you for X, Y, and/or Z and then let's go with the MRI"? I'm usually a glass is half-full person, and do not want to pretend that I have something that you all are for sure dealing with. I'm never sick, in good health, and middle-aged (is 42 middle age any more?) but have this strange thing going on in my ear and have the feeling that my luck has run out.
I belong to a number of discussion forums but this has to be the most thoughtful, informative, and supportive place I've ever set my cyber foot in. I've read the posts where after people are cleared from the AN diagnosis they just disappear, so I was never sure what else it could be to parallel the symptoms so closely. I live just north of Denver so I've already done some research (thanks to posts here) about the treatment possibilities.... I guess I just listen to the tone and wait.... Any insights are very much appreciated.