Despite there being a wide array of sight loss conditions, many of which remain without a cure, only about 1.5 percent of national research funding is invested in eye research. We pride ourselves on funding research into rare sight loss conditions and  are committed to helping develop treatments. Below you will find information on five rare sight loss conditions and how to identify them.

1. Birdshot chorioretinopathy

What is it? Birdshot is a condition that affects the retina – the light-sensitive layer of the eye – and the choroid – the layer of blood vessels that supply the retina. People with the condition will develop light-coloured spots on their retina.

How does it first present? Everyone who develops birdshot will experience a slightly different combination of symptoms, but almost everyone will have flare-ups of inflammation in the eye. In its earliest stages, birdshot chorioretinopathy will present as painless vision loss, to some degree, in one or both eyes.

For a full list of symptoms, how birdshot is diagnosed, and treatments, please visit this page.

2. Corneal dystrophy

What is it? Corneal dystrophies are inherited eye conditions that affect the cornea – the clear front surface of the eye. Abnormal material builds up in the cornea, causing it to become cloudy.

How does it first present? Symptoms include a gritty feeling in the eye, blurred vision, and eye pain. Corneal dystrophies generally worsen over time.

For details on how corneal dystrophies can be inherited, different types of corneal dystrophy, and treatments, please visit this page.

3. Stargardt disease

What is it? Stargardt macular dystrophy (or Stargardt disease) is a genetic eye condition that causes progressive central sight loss. It is a result of progressive damage to the macula, an area at the centre of the retina responsible for our sharp, straight-ahead vision. Most people with Stargardt will maintain their peripheral vision, however their central vision will worsen progressively.

How does it first present? The symptoms of Stargardt most commonly begin in late childhood, but progression is different for everyone. Individuals may experience blurry vision that makes reading fine print or distant text difficult or have difficulty distinguishing between colours. Eventually blind spots will appear at the centre of their vision which will expand over time.

For more information on progression, diagnosis, and treatment, please visit this page. 

4. Uveal melanoma

What is it? Uveal melanoma is a type of eye cancer. Tumours begin in the melanocytes – the cells that give eyes their colours – though the exact cause is unknown. 

How does it first present? Which symptoms develop depends on where exactly the tumour is growing within the uvea (the middle layer of the eye) but they can include: blurred vision, seeing flashes of light and/or floaters, a change in eye colour, and changes to the field of vision. Uveal melanoma is likely to be detected at a routine eye exam.

For more information on treatment, latest research, and clinical trials, please visit this page.

5. Wolfram syndrome

What is it? Wolfram syndrome is an inherited condition that causes sight loss as well as presenting with other non-optic symptoms. It is caused by damage to the optic nerve – the connection between the eye and the brain.

How does it first present? People with wolfram syndrome start to lose vision in early childhood and almost everyone affected is eventually registered as blind. It begins with loss of central vision, as well as the inability to distinguish between colours and fine contrast.

For more information on the different types of wolfram syndrome, treatments, and latest research, please visit this page. 

6. Aniridia 

What is it? Aniridia is a rare congenital eye condition that occurs when the coloured part of your eye (the iris) doesn’t develop properly. The word aniridia literally means ‘no iris’. There are two main causes of aniridia: genetic or as part of another condition. 

How does it first present? You can often see signs of the condition very soon after a baby is born, the most obvious of which is how the eyes look. In aniridia the iris is partly or almost completely missing, which makes the pupils look very big or an unusual in shape. 

For a full list of symptoms, how aniridia is diagnosed, and treatments, please visit this page.

7. Acanthamoeba Keratitis

What is it? Acanthamoeba keratitis (AK) is a serious eye infection of the cornea, the clear surface or window at the front of the eye. The infection is caused by a microscopic amoeba (a single-celled organism) called “acanthamoeba” which is commonly found in rivers, lakes, seawater, soil and air.  

How does it first present? The symptoms of AK include eye redness, light sensitivity, blurred vision, watery eyes and feeling like there is something in your eye. AK can cause severe pain, although the pain varies and may not be painful in the early stages. 

If you have any of these symptoms, particularly if you wear contact lenses, seek medical attention as soon as possible. 

Living with acanthamoeba keratitis: Jim's story

Common risk factors of AK 
 

• Use of reusable contact lenses 
• Using tap water to clean or store contact lenses 
• Disinfecting contact lenses incorrectly – such as by not following the manufacturer’s instructions 
• Reusing solution or topping up the solution in the lens storage case 
• Failing to empty and dry the lens storage case properly after use. 
• Poor lens handling hygiene – such as putting lenses in with wet hands after washing them in tap water 
• Swimming, using a hot tub, or taking a shower while wearing lenses 
• An injury to the cornea (such as a scratch or abrasion) 

For more information about AK visit our A-Z page