This condition is a dome-like swelling of the retina due to a leakage of fluid from beneath the retina. Some people experience blurred vision, and some distorted vision. Some people describe a circular gray spot in their vision, and some people have disturbed color vision. This condition usually goes away spontaneously with little permanent loss of vision. Some times a laser surgery can help to speed the resolution.
Many cases recur.
This usually causes a sometimes severe shift in the glasses prescription toward farsightedness. Thus, a normally nearsighted person may see an improvement in their vision without glasses. However, a person not using glasses, or who is already farsighted, will see a worsening in prescription. Once the blood sugar is controlled, the glasses prescription will revert back to normal over a period of weeks. Usually both eyes are affected at the same time.