Both eyes being involved is indeed more serious. Statistics show about 80% of patients will have significant vision decline, ranging from mild (for example from 1.0 down to 0.8) to very severe (down to below 0.2). Inflammation will damage the fine structure of the eye, like a camera covered in dust. Early intervention can significantly reduce the risk; doctors emphasize this again and again. Every time I hear “inflammation is getting controlled” at a check-up I breathe a sigh of relief, because my many experiences of not being able to see the blackboard are deeply engraved in my heart.