Pathological myopia

Myopia is short sightedness. For most people, eyesight can be easily corrected using glasses or contact lenses to make vision clear and crisp. Most people with myopia have healthy eyes.

Pathological myopia is different from simply being short sighted. Pathological myopia means that you are very short sighted and that this has caused degenerative changes to the back of your eye. Pathological myopia can cause a reduction in your sight that cannot be corrected with glasses or contact lenses.

This page contains a summary of our information on myopia and pathological myopia. To read our full information, download our factsheet:

Pathological myopia affects people with higher levels of myopia. The risk is highest when you have a glasses prescription of more than - 6 dioptres.

Not everyone with high myopia will develop pathological changes, and their eyes may remain healthy. The higher your myopia is, the greater your risk is of developing pathological changes.

Having high myopia usually means that your eyeball is longer than usual. This lengthening of your eyeball causes your retina to become thinner and stretched. This stretching can lead to changes to the retina that can cause a reduction in your sight. The changes may get worse with time or remain stable for many years. It depends on which changes have developed. In some people, the changes affect their sight very little, but if the central part of your retina, known as the macula, is involved, then your sight may be more affected.

Retinal atrophy

As you become more myopic, your eyeball becomes longer. This causes your retina to stretch and become thinner. Areas of your retina can become so thin that they no longer work. These are areas of retinal atrophy.

When an optometrist or ophthalmologist looks into your eye, areas of atrophy look very pale. These areas are so thin that blood vessels behind the retina can be seen through them. If you have areas of atrophy on your retina, your vision at these areas may be reduced. You may even have blank patches in your vision. Retinal atrophy can occur anywhere on the retina. If retinal atrophy occurs at the macula, your detailed central vision in that eye will be affected.

Unfortunately, there is no treatment for retinal atrophy, but your eyes should be monitored by your optometrist or ophthalmologist. If you notice any changes to your vision, you should have your eyes checked straight away.

Lattice degeneration

At the far edges of your retina your optometrist or ophthalmologist may be able to see a type of retinal thinning known as lattice degeneration. Lattice degeneration doesn’t cause any symptoms and is often detected during a routine eye test.

Most people with lattice degeneration don’t need any treatment. This is because lattice degeneration itself doesn’t cause any problems with your sight. Your optometrist or ophthalmologist will monitor your eyes for changes that can happen because of your lattice degeneration.

In some cases, lattice degeneration may be associated with a retinal tear. If this happens, it may be treated with laser treatment, known as laser retinopexy, or cryotherapy (freezing treatment). These treatments seal the tear and prevent it from developing into a retinal detachment.

It’s important to be aware of any new or changing symptoms such as floaters and flashing lights. If you do experience any new symptoms, you should have your eyes examined straight away by your optometrist, at your local A&E or eye casualty.

Lacquer cracks

As the eye stretches it can cause breaks to occur in the layer known as Bruch’s membrane. Bruch’s membrane lies between the retina and its underlying blood supply from the choroid layer. Your optometrist or ophthalmologist can see these breaks as fine lines on the retina. These are known as lacquer cracks. There isn't any treatment for lacquer cracks. They don't affect your vision directly, but they can be the first signs of further problems developing which can cause changes to your vision. Therefore, if you have lacquer cracks your ophthalmologist or optometrist will monitor your eyes closely.

New blood vessels (neovascularisation)

New blood vessels can sometimes grow from the choroid layer underneath the retina. They come through lacquer cracks or areas of atrophy onto the retina. This is known as choroidal neovascularisation (CNV). These new blood vessels are very weak and fragile and leak blood and fluid, causing damage and swelling to the retina. This damage causes scarring, which can permanently affect your vision. Neovascularisation can occur anywhere on the retina. If CNV occurs at the macula, it can significantly affect your vision.

Myopic macular degeneration

If any of these degenerative changes develop at the macula, it’s known as “myopic macular degeneration” or “myopic maculopathy”. This can affect your central detailed vision and colour vision. Changes to your central vision can make it difficult to read and see people's faces clearly and cause straight lines to look bent or distorted.

Myopic macular degeneration may be referred to as “dry” or “wet”. “Dry” myopic macular degeneration is when there is retinal atrophy, thinning of the retina, or scarring at the macula. Unfortunately, there isn’t any treatment for dry myopic macular degeneration.

“Wet” myopic macular degeneration is where there is growth of new blood vessels at the macula. This is often referred to as myopic choroidal neovascularisation or myopic CNV.

Myopic CNV can develop quickly, and symptoms can include:

• distortion, straight lines appearing wavy, curved or bent
• blurry vision
• a blind or grey spot in the centre of your vision
• colours looking dull or different than usual.

If you suddenly notice any of these symptoms, it’s important to have your eyes checked straight away by your optometrist, or at your local A&E or eye casualty. . You can also call 111 for advice on where to go.

About five to ten out of 100 people with pathological myopia develop myopic CNV. It is possible to develop myopic CNV in both eyes but in most cases, it affects only one eye.

If you start to develop new blood vessels at the macula, this can be treated with anti-vascular endothelial growth factor (anti-VEGF) medication. Anti-VEGF medications work by reducing the growth of new, leaky blood vessels and the swelling (oedema) they may cause. This treatment can reduce the risk of scarring and damage to the retina caused by these new vessels. This can help to prevent further deterioration in sight.

It’s important that myopic CNV is treated quickly, before there is too much damage to the macula. The aim of the treatment is to stop any further new blood vessels from growing, and further deterioration in your sight. But, in some people, treatment may also help to improve their vision.

Generally, myopic CNV responds well and quickly to treatment with anti-VEGF.

Anti-VEGF medicines are injected into the vitreous gel within the eye. This is called an intravitreal injection. The injection is given in a clean sterile room or an operating theatre to reduce the risk of infection. Before the injection, you’ll be given anaesthetic eye drops to make your eye numb, so the injection is not painful.

You can find more information about anti-VEGF treatment on our website rnib.org.uk/eyehealth, or by calling our Helpline 0303 123 9999.

Förster-Fuchs spot

Myopic CNV can cause scarring to develop at the macula after the new blood vessels and bleeding have gone. This leaves a circular area of pigment known as a Förster-Fuchs spot. The scarring can cause a blank or missing patch in your central vision. Unfortunately, there is no treatment for retinal scarring.

Myopic foveoschisis

Pathological myopia can sometimes cause myopic traction maculopathy (or myopic foveoschisis). This happens when an area of the back of the eye develops an extra bulge outwards, called a posterior staphyloma. As the bulge forms, it stretches and thins the white of the eye (sclera) and the choroid layer underneath the retina. This stretching can cause splitting of the retinal layers at the macula.

Myopic foveoschisis develops slowly and at first may not cause any changes to your vision. As it progresses, it can cause your central vision to be blurred or distorted. In the later stages, it can cause a macular hole or retinal detachment to develop, which require surgery to repair. More information about macular hole and retinal detachment can be found on our website or by calling our Helpline.

If you have high myopia, there are no treatments available to stop your eye from developing pathological myopia. There is currently no evidence to suggest that diet, vitamins or supplements can affect your chances of developing pathological myopia or make it better or worse.

Currently treatment is aimed at improving your vision and treating any complications if they happen. You will be monitored regularly by your optometrist or ophthalmologist who will check the health of your eyes. It’s important to have your eyes checked by your optometrist or ophthalmologist as soon as possible if you notice any changes to your vision or any new symptoms.

Most people who have myopia don’t have any complications and will only ever need glasses or contact lenses to correct their focusing error and make their vision sharper. If your prescription is -10.00D and over, then you would be allowed an NHS complex lens voucher to use towards the cost of your glasses or contact lenses. Your optician will be able to tell you if your prescription is -10.00D or over and how much this voucher is worth.

The higher your level of myopia , the higher the risk of developing pathological myopia. If your retina has been damaged, then your vision may need more than prescription glasses to help you to see well.

Having pathological myopia can cause changes to your vision in the long term, but much can be done to help you make the most of your remaining vision and adapt to any changes.

There is much that can be done to help make the most of your sight you have. This includes visual aids and adaptations around the home, adaptations and specialised software for computers at home and at work, and training from social services. Our Advice service can help provide information about all the different practical support available, contact our Helpline to speak with them.

You can also find out tips for making the most of your sight by downloading our booklet:

The Macular Society offer local support groups for people with macular eye conditions or central vision loss. They have working age and young people support groups and online condition specific support groups via Zoom. This includes a support group specifically for people with myopic macular degeneration.

macularsociety.org