Thanks to everyone for your responses. They all really do help!

Annie, in reponse to several of your questions:
Yes, I do have binocular double vision. It always disappears when I close one eye.

I've had antibody tests drawn several times. One of them was a binding. I also had MUSK test done as well. The SFEMG that I had was done shortly after my symptoms started 7 years ago. At that time I was seeing a neuro ophthalmologist. Before I had the tests he said he was quite sure that I had MG--after the tests were negative, he headed in a different direction.

That's why I was quite surprised that the pursuit of a MG diagnosis resurfaced recently. Interestingly, I've been dealing with an increase in double vision since I had surgery a little over a year ago.

I don't know if my current neurologist is an MG expert. Over the years, I haven't stuck with 1 neuro (mostly out of frustration and feeling like I wasn't being listened to). I did check and this neuro does see others with MG. The ophthalmologist who saw me recently for the concerns with an increase in my double vision recommended this neuro.

BTW, your visual description of double vision looks very similar to what I see, except sometimes one of the lines is slanted.

Again, thanks all for your support. And, yes...not knowing is the hardest part.

Cate