Retinitis Pigmentosa

The light sensitive part of the back of the eye (retina) is made up of two types of photoreceptive cells, cones and rods.  Approximately 6 million cones cells make up the macular, the central part of the retina which accounts for the sharp central vision and sees colour.  Approximately 125 million rods form the outer part of the retina and account for the outer, peripheral vision.  Whilst the cones work better in bright light the rods are used for night vision, hence colour perception being less accurate in low light.

What is a Retinitis Pigmentosa (RP)?:

 Retinitis is disease or inflammation of the retina causing dark spots of pigment (pigmentosa).  Retinitis Pigmentosa actually covers a wide range of different types of hereditary eye problem. Sight loss is gradularly progressive as the cones or rods are effected though complete blindness from Retinitis Pigmentosa is rare.  Retinitis Pigmentosa causes nearly 2% of blindness or visual impairment in the UK.

Symptoms:

 Some types of Retinitis Pigmentosa effect the cone cells, making central vision impaired, making detailed work like reading, difficult.  Retinitis Pigmentosa which effects the rod cells causes a narrowed visual field, or tunnel vision.  Sufferes can have difficulties seeing in very bright on dim light, though this normally develops as the condition progresses.

People with Retinitis Pigmentosa ofter develop cataracts, Ushers Syndrom (hearing loss) and other conditions.

Children that show signs of Retinitis Pigmentosa may also have other symptoms with no relation to their vision, such as learning difficulties, impaired hearing and reduced growth.  In most cases early symptons appear between the ages of 10 and 30.

Causes:

Retinitis Pigmentosa is genetic and is often caused by a gene inherited from one or more parent, though it can skip generations. 

Treatment:

As Retinitis Pigmentosa is genetic, as yet, there is no cure or prevention for the progression the condition.  There is currently research into the possibilty of retinal implants, drugs and stem cell research.

Links:

For a more detailed and expert opinion visit:

• The British Retinitis Pigmentosa Society web site
• RNIB pageon Retinitis Pigmentosa