How does diabetes affect the eye and vision?
To understand how the eye is affected by diabetes, it is necessary to understand how the eye works and how we see the world around us. The eye works like a camera. The images from the world around us are focused by the cornea and lens on the retina, which is in the back of the eye and is similar to the film in a still camera or the CCD chip in a video camera. The light rays pass through the center of the eye where there is a clear, jelly-like substance called the vitreous. The retina processes the image like a video camera and sends these signals to the brain along a “cable” called the optic nerve. Pressure in the eye is maintained by a system of fluid production and drainage. The drainage area of the eye is at the edge of the iris and is called the trabecular meshwork. If this fluid flow is interrupted by blockage of the drain, the pressure in the eye becomes elevated and glaucoma develops. Diabetes may affect the lens of the eye (cataract), the retina (diabetic retinopathy), the flui
