Myopic maculopathy: when short-sightedness damages the macula

Myopia, or short-sightedness, is common and in most people is easily corrected with glasses or contact lenses. The NHS describes short-sightedness as usually starting in children from age 6 to 13 and as often running in families, and RNIB points out that most people with myopia have healthy eyes. In a small number of people with very high myopia, the stretching of the eye causes degenerative change at the back of the eye, which is called pathological myopia.

Myopic maculopathy is the form in which these changes involve the macula, the central part of the retina responsible for detailed vision. RNIB uses the terms myopic macular degeneration and myopic maculopathy for degenerative changes at the macula, which can affect central detailed vision and colour vision. The changes may get worse with time or stay stable for many years, depending on which changes have developed.

RNIB describes a set of changes that can occur, each with different implications. They are summarised in the table.

RNIB says changes to central vision can make it difficult to read and see faces clearly and can cause straight lines to look bent or distorted. Wet myopic macular degeneration (myopic CNV) can develop quickly. Its symptoms include distortion with straight lines appearing wavy, curved or bent, blurry vision, a blind or grey spot in the centre of vision and colours looking dull. About five to ten out of 100 people with pathological myopia develop myopic CNV, usually in one eye.

If you suddenly notice any of these symptoms, RNIB advises having your eyes checked straight away by your optometrist, or at your local A&E or eye casualty, and that you can call 111 for advice on where to go. New floaters, flashing lights or a curtain across vision need urgent assessment too, because high myopia is associated with retinal tears, and RNIB advises examination straight away for new or changing floaters and flashing lights.

Changes are seen when an optometrist or ophthalmologist looks at the retina, and atrophic areas look very pale because blood vessels behind the retina can be seen through them. The NHS says an optometrist may use special eye drops so that the back of the eye can be seen more clearly during an eye test.

People with high myopia should have regular eye examinations. RNIB says that if you have areas of atrophy, lacquer cracks or lattice degeneration, your eyes should be monitored and any change in vision should be reported straight away. RNIB says it is important to have your eyes checked as soon as possible if you notice any change in vision or new symptoms.

RNIB says there is no treatment for dry myopic macular degeneration, for retinal atrophy or for scarring. For wet disease, anti-vascular endothelial growth factor (anti-VEGF) medicine reduces the growth of new, leaky vessels and swelling, reducing the risk of scarring and damage, and can help prevent further deterioration. It says myopic CNV must be treated quickly, before too much macular damage occurs, and that it generally responds well and quickly. In some people, treatment may also improve vision.

Anti-VEGF medicines are injected into the vitreous gel of the eye, an intravitreal injection, in a clean sterile room or theatre after anaesthetic drops numb the eye. For macular holes or retinal detachment, surgery is needed. Treatment is delivered by NHS hospital eye services, and some people also use private ophthalmology clinics for quicker access; the medicines used are the same.

Many people retain good side vision and function with low-vision support. RNIB offers a helpline (0303 123 9999), a factsheet on pathological myopia and advice on visual aids, adaptations around the home and specialised computer software. The Macular Society, which RNIB signposts, runs local and online support groups including one for people with myopic macular degeneration. RNIB also notes that an NHS complex lens voucher is available towards the cost of glasses or contact lenses if your prescription is -10.00D or over.

RNIB states there are no treatments to stop high myopia becoming pathological myopia, and no evidence that diet, vitamins or supplements make a difference. Regular monitoring by an optometrist or ophthalmologist is the main safeguard, with prompt review of any new symptom.