My doctor says i've got macular edema. what does this mean?

Macular edema: This is a swelling of the layers of central retina in your eye. Because light rays are focused on the central retina, any swelling here can blur and threaten vision. The causes of macular edema are best determined by an eye exam and further testing. the treatment depends on the underlying cause

Edema: Macular edema: fluid has accumulated under your macula: could be from various reasons: stress, diabetes, trauma.