It is a below-average ability to see at night or in low light. It is not a disorder in itself, but a indication of underlying condition. It can occur at any age. Night blindness, called as nyctalopia or impaired dark adaptation, is caused due to a disorder of the cells in the retina that are responsible for vision in dim light. It may be caused due to Cataracts, Myopia, glaucoma, vision problem, choroideremia, Retinitis pigmentosa, Usher syndrome.