The chances of developing diabetic retinopathy increase the longer a person has had diabetes and the more severe the case. Changes Functional Changes 1. Preclinical Small but significant changes can be observed in electroretinograms, but not in a routine retinal exam. Patients cannot detect any vision changes. These changes are visible only in an eye exam, when the pupils are dilated.
Some individuals perceive no vision changes.
Macular edema, if present, may cause difficulties with reading and other activities involving close vision. These vessels can break and bleed into the vitreous, preventing light from reaching the retina. Macular edema may be evident. Spotty or cloudy vision. The retina grows more abundant new blood vessels, glial scars may be evident, and the retina may even detach.