Although not a pilot, a friend of mine had this operation for the same condition about six weeks ago. He recovered very quickly and his eyesight(eyeball) was utterly unaffected, apart from the obvious benefit of no longer having a droopy eyelid.
If I were suffering from the same complaint, I wouldn't hesitate to get the op, and I would be confident it wouldn't affect my flying either in the real world or my ability to pass a class 2 medical.