When we really think about how the human body works, muscles are seen as the power stores that drive us. Think of muscles and we visualize hard bodied sport’s men and women with sculpted bodies, perfect specimens of fitness and health. There are however some tiny muscles that most of us take for granted, which we use every waking moment in our visual system. They work tirelessly throughout the day to make our eyes work together and give us the gift of sight.

The movement of each eye ball is controlled by six muscles, called extra ocular muscles, which hold the eye in place and enable it to move. This gives us the maximum vision all around us, and helps both eyes to work together. Shut each eye individually and you’ll realize that you see a slightly different image with each eye, but by controlling the movements of both eyes and the brain then fusing the two images together, most of us don’t suffer from double vision.

Problems arise if your muscles don’t work together, and the eyes don’t turn together. Injury or disease such as stroke can cause difficulties with this, stopping the two eyes from co-ordinating their movements. Some of us are born with abnormalities in the length of a muscle, which means one eye is out of alignment. This can be corrected by surgery.

Opticians correct double vision by using a prism built into your spectacle lenses. The prism bends the light so that you only see one image. This can be put into one or both lenses, and usually we divide the prism up so that the weight is even across both lenses. We also use prisms that stick onto lenses sometimes, this allows us and you to experiment with the amount of prism needed, or correct a temporary problem. When you’re tired the double vision can be worse, as your eye muscles suffer from fatigue just like aching legs or arms! To prevent eye strain and overworking those busy eye muscles, always wear glasses if they have been prescribed, take breaks from close work at regular intervals, and visit your optician at once if you suddenly suffer from double vision. All less tiring than a visit to the gym!