Myopia

Description

Myopia, also called shortsightedness or nearsightedness is the most common cause of visual impairment in people under the age of 40. Roughly one quarter of the worlds’ population are nearsighted. Myopia causes difficulty in focusing clearly on objects that are far away. There is not usually an issue noticed with reading or close-up work. Often the use of glasses with the correct prescription can alleviate the symptoms of myopia.

Symptoms

Children may persistently squint their eyes when looking at objects further away or for example may have difficulty reading the board in a classroom if they sit too far away. Parents may also notice excessive blinking and frequent rubbing of eyes if their children have myopia. Adult individuals can identify blurred vision when focusing on objects that are far away. Individuals may also notice the need to partially close their eyes to see more clearly. Persistent eyestrain can manifest as headaches and drivers may notice difficulty while driving at night time.

Causes

Vision occurs when light rays are bent as the pass through the front window of the eye (cornea) and the lens. This light is then focused on the retina at the back of the eye where it is converted into messages that are delivered to the brain, and interpreted as images. With myopia, light rays from nearby objects are not focused properly onto the retina, but instead they’re focused on a point in front of the retina. This is due to the eyeball being too long, having a lens which is not able to focus light onto the retina properly or having a cornea which is too curved. Myopia generally begins in early childhood with an increased risk if both parents are also myopic. In most cases myopia stabilises in early adulthood (does not continue to get worse), but sometimes it can continue to progress with age.

Diagnosis

Myopia is diagnosed through a number of tests which are important for providing the correct diagnosis. This can include taking clinical tests, medical history and a family history. A harmless medical device known as a retinoscope is used to shine light inside the eye to observe the reflection off the retina. A refractor may also be used to measure the exact refractive error (level of near-sightedness in this case) of the eyes. This will help to determine the correct glasses prescription to correct the visual impairment. All eye movements and coordination abilities will be examined. The eye care professional will examine the eyes for signs of any other eye conditions which may be causing myopia.

Treatment

There is no cure for myopia, however with glasses or contact lenses the nearsightedness can be corrected by altering the way in which light rays bend in the eye. Some people with myopia may not need to wear their glasses or contact lenses all the time, just in situations where they are driving for example. Refractive surgery, also known as LASIK, is an alternative option for correcting myopia. Surgery may reduce or eliminate the need for glasses or contact lenses, however it is possible to develop the need for visual aids once again as you naturally age. General eye check-ups are important for people living with myopia, as these individuals may still be at risk of developing other kinds of eye problems that affect the general population, some of which may be treatable. No matter what level of vision a person may have, it is important to look after the eyes. To find out more about what can be done to take care of the eyes on a daily basis, please visit our Tips for Good Eye Health. For further information, please contact the Research Department on 01 6789004 or email research@fightingblindness.ie.

Research

Researchers and clinicians are continually seeking more effective approaches to stop the progression of myopia. These approaches include the use of topical eye drops, assessing the benefits of increased outdoor time, and orthokeratology- the use of rigid permeable contact lenses that re-shape your cornea (front of the eye) over time. A Fighting Blindness funded research, Prof James Loughman, is currently investigating the use of atropine eye drops as a treatment for childhood myopia. Information about clinical trials that are on-going and completed can be found on the clinical trials website and can be searched by both condition and location.

Support

Receiving a diagnosis can be overwhelming for anyone, but this is not a journey that you have to make alone. There are many groups and resources available to provide support for people living with Stargardt Disease. Fighting Blindness offers a free and confidential counselling service (Insight Counselling). For further information please contact insight@fightingblindness.ie or call 01 6746496. We also offer support groups for people with a visual impairment to share their feelings and experiences with others facing the same challenges. Please consult the support groups section of our website here to access the latest timings and days for the various support groups we offer. For further information please contact insightgroups@fightingblindness.ie or call 01 6746496.

Resources

Féach provides support for parents of children living with sight loss in Ireland. ChildVision is the national education centre for children with sight loss in Ireland. NCBI (National Council for the Blind in Ireland) provides support and services for people living with sight loss in Ireland. Irish Guide Dogs for the blind helps individuals and their families to achieve improved mobility and independence.