What is retinal degeneration?

The retina is the light-sensing layer at the back of the eye. It is like the photographic film in a camera. In some retinal degenerative disorders there is a gradual deterioration of the retina while other conditions affect only the retina used for central vision. The type and severity of the clinical symptoms vary according to the specific disorder. Common symptoms are loss of night vision and side vision in retinitis pigmentosa and loss of central (reading) vision in macular degeneration.

Approximately 1,000 people in NZ are affected with retinitis pigmentosa and about 10,000 people with age-related maculopathy. Collectively retinal degenerative disorders are the most common cause of blindness.

What is the cause?

Some retinal degenerative conditions such as retinitis pigmentosa are strongly hereditary. This means that a defect in a single gene can give a person a very strong likelihood of developing retinal degeneration.

The genetics of other retinal degenerative disorders such as age-related maculopathy are currently poorly understood.

It seems that both genetic susceptibility and environmental factors play important roles in age-related maculopathy.

There are three main types of inheritance pattern for the strongly hereditary retinal degenerations:

• The recessive type often occurs with no known family history of the eye disease and can affect members of either sex. Both parents are carriers. It is estimated that one person in 80 carries a gene for recessive retinal degeneration.
  
• The dominant type usually appears in successive generations in an affected family. A person with this type has a 50% chance of having an affected child with each birth. Diseases inherited by the dominant type are usually a less severe form.
  
• The sex-linked type is transmitted by female carriers to their sons. Affected males cannot transmit it to their sons, but all of their daughters will be carriers. The son of a female carrier has a 50% chance of being affected, while her daughter has a 50% chance of being a carrier. Female carriers of some retinal degenerative disorders are detectable.

Age Related Macular Degeneration

New Zealand statement for release, Friday 17 Sept 1999
Prepared by Anthony Haas

Macular degeneration - a public health challenge

An international alliance to create world-wide awareness of the problem of age related macular degeneration (AMD) is to be launched immediately following World Retina Day, 25 September.

Retina New Zealand is expanding its own public education contribution by launching its website: www.retina.org.nz on World Retina Day.

The alliance plans to launch an aggressive international general consumer awareness campaign with a focus on seniors and their caregivers to raise visibility of AMD and ignite effective action such as screenings and eye exams.

It aims to mobilize the medical community, insurance industry and key governmental decisionmakers to recognize and support AMD as a health priority.

The outgoing president of Retina New Zealand, June Ombler, says the local voluntary organisation is arranging to become an associate member of the AMD Alliance. Retina International, whose mission to do everything to promote research into Age Related Macular Degeneration, is joining the association says Swiss based president Christina Fasser.

Retina New Zealand, a voluntary consumer organisation, has been fostering New Zealand participation in international research which has produced breakthroughs in understanding of the genetic makeup of the retina, and points towards human clinical trials of treatment options.

AMD's plan reflects the research and resources of the Alliance membership, Ketchurn Worldwide and CIBA Vision.

AMD's mission is:
To bring knowledge, help and hope to individuals and families around the world affected by Age-Related Macular Degeneration (AMD) by:

• Generating awareness and understanding of Age-Related Macular Degeneration.
  
• Promoting the importance of education, early detection, knowledge of treatment and rehabilitation options.
  
• Preserving vision and improving the quality of life of individuals affected by Age-Related Macular Degeneration.

Age and sight

Membership is open to top vision care organizations that are dedicated to vision preservation and blindness prevention, and top senior care organizations that are focused on maintaining and improving quality of life as people age.

AMD Alliance International founding members include the Association for Macular Diseases, the Canadian National Institute for the Blind, the European Federation of the Elderly, the US Foundation Fighting Blindness, the International Federation of Ageing, Lighthouse International, Macular Disease Society, ORBIS International, Prevent Blindness America, the Royal National Institute for the Blind and the Seniors Coalition.

Millions affected

Approximately 25-30 million people are affected globally by some form of Age-Related Macular Degeneration, AMD. Approximately 25 percent of 70+ year old adults have some form of AMD. As the average age of the global population rises, the number of people with AMD is projected to triple in the next 25 years. There are 500,000 new cases of 'wet' AMD that occur globally each year and, of those, 200,000 cases are in North America. 'Wet' Age-Related Macular Degeneration (AMD) is the leading cause of legal blindness in people over 50 years of age in the western world. Approximately 5 million people in the western world are affected by 'wet' AMD.

The annual global number of new cases of AMD is similar to the number of prostate and breast cancer cases; however, AMD is not yet considered to be a high priority health issue/crisis.

United for sight

The Alliance "motto" is United for Sight.

This phrase represents a joining of forces to combat AMD and improve the quality of life of those affected by AMD.

AMD Alliance International objectives are to;

• raise the overall awareness level of AMD and the importance of early detection;
  
• increase the number of people 50+ who receive regular eye examinations; and
  
• increase the percentage of those with AMD who receive treatment and rehabilitation options.

The international alliance plans an AMD Awareness Week next year, a toll-free hotline, a web site, trade show exhibits, a speakers bureau, a doctor/patient outreach programme and a media campaign.

The incoming President of Retina New Zealand Anthony Haas says his vision is for the society to foster greater support and action for blindness prevention in New Zealand.

"As long as we make our own contribution to the collective effort we can benefit from the increasing contributions others are making overseas to blindness prevention" he says.