I can't see what's going on.

1. Refractive error

genetic factors can

cause refractive error

, external parallel light can not be gathered in the retina macular normally, easy to appear blurred vision, vision symptoms.

2. Cataract

nutritional disorders, metabolic abnormalities and other reasons can cause cataract, patients may appear lens turbidity, at this time will also appear blurred vision symptoms.

3. Keratitis

pathogenic microbial infection can lead to keratitis, corneal tissue can appear inflammatory lesions, inflammatory stimulation can cause local congestion, edema, causing the symptoms.