Myopia, or short-sightedness, has become much more prevalent world-wide in recent years. It occurs when light is focussed in front of your retina instead of on your retina, meaning that objects in the distance are blurred, such as when driving or watching television. Close vision, such as when reading, remains clear. There are many well known risk factors for myopia development, both genetic and environmental, and your optometrist will spend some time looking at these.
Myopia typically starts during childhood, and is a progressive condition. It usually stabilises around the time when children finish growing. In fact, the younger the child when myopia starts, the more chance a child has of developing high levels of myopia, which persist into adulthood.