What are macular degenerative diseases?

There are many. causes of degeneration of the macula. In younger patients they are usually genetic mutations (e.g. North Carolina Macular Dystrophy), and later in life they are age related (e.g. Age Related Macular Degeneration) but a genetic predisposition is required, not everyone gets it. Since the macula is where 'central vision' is captured, when the macula degenerates, the visual acuity worsens.