THIS ART IMAGE SHOWS WHAT A PERSON SUFFERING FROM ADVANCED GLAUCOMA AND RP WOULD SEE

Both these conditions in there later stages can lead to tunnel vision as the art aims to depict, but they manifest in very different ways.

Glaucoma is characterised as a condition which causes damage to the optic nerve which can be caused by increased intra-ocular pressure although in many cases the pressures are normal and damage may be due to an actual weakness of the optic nerve. This optic nerve is responsible for sending all the information received by the retina and macula and transmits it via the optic pathway to be processed at the back of the head in the visual cortex. The subtle and slow changes to the optic nerve leads, to a progressive loss in field of vision and if untreated will ultimately lead to blindness.

There are many types of glaucoma namely:

1/ Primary open angle glaucoma (POAG)

2/ Normal tension glaucoma

3/ Primary angle closure glaucoma

4/ Ocular hypertension.

Glaucoma can be more prevalent in different sections of the community. For example POAG is more common in those aged 40 yrs and over, higher incidence in African ethnicity, family history and short sightedness (myopia). Open angle glaucoma is symptomless and as mentioned leads to a progressive visual field loss and is usually bilateral. Please click on the links below to find more information.

http://www.rnib.org.uk/xpedio/groups/public/documents/PublicWebsite/public_rnib003655.hcsp

http://en.wikipedia.org/wiki/Glaucoma

http://www.glaucoma-association.com/nqcontent.cfm?a_id=176&=fromcfc&tt=article〈=en&site_id=176

RETINITIS PIGMENTOSA

Retinitis pigmentosa (RP) is a generic name for a group of hereditary disorders which is characterised by a loss in RPE and photoreceptor function. It presents with night vision problems and peripheral visual fields changes but later detailed close vision and colour vision can be affected. The incidence is usually around 1 : 4000 people. It can manifest in different ways

1/ Autosomal dominant – most common with approximately 43 % cases

2/ Autosomanl recessive – approx. 20 % cases

3/ X-LINKED recessive – approx 8 % cases

4/ Sporadic – occurs without any family history and accounts for approx. 23 % cases.

The main clinical features of RP are, bilateral involvement, loss of peripheral vision, rod dysfunction and progressive loss of peripheral vision. The classical triad of seen are, arteriolar attenuation, retinal bone-spikule pigmentation and waxy disc pallor.

Please click on the links below for more information about RP.

http://www.brps.org.uk/index.php?tln=aboutrp

http://www.rnib.org.uk/xpedio/groups/public/documents/publicwebsite/public_rnib003662.hcsp