Retinitis pigmentosa is a genetic disease which causes progressive and irreversible damage to the retina, resulting in blindness. It affects about 1 in 4,000 people. There are at least 50 genes known to cause retinitis pigmentosa, and inheritance patterns vary.
It is the most common cause of inherited blindness.
- Often begins as night-time blindness – sometimes in childhood, but may be later
- Reduced visual fields – starts peripherally and extends towards the centre
- Blindness occurs between adolescence and middle age
- Irreversible – can be delayed with use of vitamin A
- Degeneration of rods and cones
- Results in displacement of melanin-containing cells from deeper layers of the retina closer to the surface of the retina
- Can be seen as pigmented patches on visualisation of the optic disc
- There may also be optic atrophy