I had a severe B12 deficiency years ago. Not fun. They need to attempt to figure out WHY you have a deficiency. How low is your number? Did they test your homocysteine or methylmalonic acid? Those can be elevated during a B12 deficiency. My deficiency was caused by a lack of stomach acid.

B12 can affect the brain. Methylcobalamin is the best form of B12, going to work right away in the bloodstream. Cyanocobalamin has to be converted by the liver into methylcobalamin before going to work. Given that there is usually a six year supply of B12 in the liver, you may have had this deficiency for some time. And it can take as long to recover as you have had the deficiency.

Cancer can also suck B12 out of the body, given that it goes straight to areas of cancer. I hope you don't have that!!! But they really do need to figure out why you have a deficiency!

Some people with MG only have a positive modulating antibody. A high level of modulating antibodies can also be a sign of a thymoma (tumor of the thymus). Kind of weird that the modulating AB is slow; they are all done at the same time.

You need a MG expert neurologist, not only an eye doctor! They can do a thorough clinical exam that can show fatigable muscle weakness, the hallmark of MG. They can do all sorts of other tests, such as the Ice Pack test, Tensilon test, RNS/EMG/SFEMG, and MuSK antibody test. LRP4 is now available as well.

Do you have ptosis? I'm assuming you do because of the double vision! Obviously, you have binocular DV, since that goes away when you close one eye. Do you have an eyelid that is more dominantly droopy? If so, lift up on that one for about 10 seconds. Does that one go up and the other eyelid go down? That is called enhanced ptosis, and is another sign of MG. There's also Cogan's lid twitch and many other ways a neuro-ophthalmologist can test for MG.

You can always do an Ice Pack test at home. Take pics of any ptosis beforehand. Then put a cold washcloth on your eyelids for a few minutes. Then take a pic afterward. Use the same lighting, head tilt, etc. for the photos.

An ophthalmologist is NOT qualified to comment on MRI results. Sorry, but they are not neurologists. Get a copy of the MRI CD and bring with to a neurologist.

I hope you'll have answers soon. You may want to consult with an internist as well.

Annie