This is manifest as the loss of the ability to see fine details when reading or seeing distant objects. Symptoms typically develop before age 20 (median age of onset: ~17 years old),[3] and include: wavy vision, blind spots, blurriness, loss of depth perception, sensitivity to glare, impaired colour vision,[3] and difficulty adapting to dim lighting (delayed dark adaptation). There is a wide variation between individuals in the symptoms experienced as well as the rate of deterioration in vision.