Hi Tilusbob,
Diplopia occurs when the eye muscle sort of gets stuck in position and can't rotate the way it should. Crowding of the orbital cavity resulting from inflammation cause it to occur. Surgery for severe diplopia can help prevent permanent scarring or fibrosis, but still it's not usually needed. Usually, diplopia can be manged with special lenses and eye exercises can help keep the muscle mobile.
Autoimmune GO does run its own course independent of the eye disease. In general, TSH will remain low since it's falsely lowered by TSH receptor antibodies and they're typically high (both stimulating and blocking antibodies) in people with TED. In TED related to low or high thyroid hormone levels, symptoms improve when thryoid hormone levels are corrected and brought into the reference range. Once autoimmune GO develops, the active phase can last anywhere from several months to 5 years, although for most people the active phase runs for about 18 months. Smoking worsens TED and smokers usually have longer disease courses.
Your ophthalmologist is able to assess if your eyes are still showing signs of active inflammation. Often, MRI is used to evaluate TED and some doctors use eye measurements. In most cases of TED, surgery isn't needed and symptoms resolve on their own. Most of the ophthalmologist I've met have retired but if you venture to the states and are headed for a particular city, I'll check my connections. Best, Elaine