What is Myopia?
Myopia is often referred to as short-sightedness. People who are short-sighted have blurry distance but can see clearly up close. Short-sighted people have difficulty reading the whiteboard at school, watching TV, recognising people in the distance and often squint to improve their vision.
Myopic eyes are usually longer than normal eyes and consequently the point of focus is in front of the retina, resulting in a blurred image.
People who are myopic can achieve good distance vision with spectacles or contact lenses. Myopia usually develops in childhood and stabilises in the mid-20’s, however standard spectacles and contact lenses do not stop the increase in myopia.
Most myopia is caused by the eye length growing too quickly in childhood. It is the combination of genetic and environmental influences, and these factors will vary between individuals. Genetic factors such as parental myopia and ethnicity increase the likelihood of developing myopia. There is a significantly higher risk of developing myopia if both parents are myopic or if the parents are of East Asian or South Asian descent.
Environmental factors such as excessive close work, reduced time outdoors and issues of eye co-ordination, also increase the likelihood of developing myopia.
Myopia is now defined as a disease and has been categorised as a global epidemic by the World Health Organisation. Rates of myopia are increasing in all countries around the world, and it is estimated that by 2050, 52% of the world’s population will be myopic. The increased frequency of myopia and the earlier age of developing myopia has created concerns about the increased risk of serious eye disease associated with myopia, particularly high myopia (> -6.0). The level of myopia has doubled in Australia over the last 30 years. Over 80% of teenagers and young adults in Korea, China, Taiwan, Hong Kong, and Singapore are myopic.
Increasing myopia requires regular updates of spectacles and contact lenses to guarantee good distance vision and in some cases these changes may be needed every six months. Frequent increases in prescription can be inconvenient and expensive and previously were accepted as a “normal” process.
However, research over the last twenty years has shown that higher myopia significantly increases the risks of developing sight threatening eye diseases later in life. Myopia is no longer a matter of the inconvenience of wearing spectacles or contact lenses, it is a matter of preserving lifelong eye health.
Unfortunately, any level of myopia increases the risk of myopic eye disease. Research has shown that for moderate myopia (-3.0 to -6.0) the increased risk of developing:
- Cataract is 3x greater
- retinal detachment is 9x greater
- glaucoma is 4x greater
- myopic macular degeneration is 10x greater
These increased risks are even greater for higher levels of myopia, > -6.0. Excessive eye length is often associated with higher levels of myopia and research has shown that eyes that are significantly longer than normal have a 27% chance of permanent visual impairment by the age of 75.
The higher the level of myopia, the higher the risk of vison loss.
We use the latest technology to measure the length of the eyeball (axial length). Axial length is the most reliable, objective measure of eye growth and is used in myopia control research as the gold standard measurement. Measuring a child’s subjective prescription shows how much that prescription has increased but doesn’t indicate how much the eye has grown. Preventing eye growth is the aim of myopia control and a precise axial length measurement is essential for monitoring myopic progression, especially for children using Ortho-K treatment.
Axial length data allows us to compare your child’s measurements to normal for their age and how the eye length is changing over time. We can also use axial length growth charts to predict the likelihood of your child developing high myopia as an adult.
Currently we are unable to reverse myopia that has already developed, but we can use myopia control treatments to slow or even stop myopia progressing.
The aim of myopia control is to prevent your child from developing high myopia > -6.0.
Myopia progresses fastest in younger children, especially those under age 10 and the age of becoming myopic is getting younger. Unfortunately, this allows a longer time for the eye to become more myopic as most myopia is stable by the mid 20’s.
Myopia control treatments can significantly reduce eye growth and keep the prescription at a lower level, reducing the risk of permanent vision loss later in life. The earlier we start myopia control treatment, the greater the chance of limiting myopia progression. Evidence based myopia control treatments are available for children and adolescents whose eyes are still in the growing phase.
Adult-onset myopia occurs when people who have had excellent vision throughout their childhood and adolescent years, develop myopia. Research has shown that 30% of myopes develop their myopia after the age of 17. There is limited research on adult-onset myopia, however it is believed to be caused by poor eye focussing associated with the significant hours of screen time. We recommend using the myopia control treatments that are well proven for children and adolescents, until new evidence-based therapies are available.
We can implement a range of options to reduce the rate of myopia progression.
Reading and Screen Time
Prolonged periods of screen and reading time have an influence of the risk of developing myopia and have the greatest impact before the age of 12.
Home screen time should less than 2 hours/day.
Screens, phones, or books should be held no closer than the distance from the hand to the elbow.
Read in good lighting.
After 30 minutes of close work, take a 10-minute break and walk around.
There is compelling evidence that increasing outdoor time can prevent the onset of myopia and some evidence that outdoor time can reduce the progression of myopia. It is believed that the increased light levels outdoors in some way reduces eyeball growth and the development of myopia. Sun protection is still important and even when wearing sunglasses and playing in the shade, the light levels entering the eye are still substantially higher than indoors and so are protective for myopia development.
90 minutes of daily outdoor time is recommended.
Myopia is associated with an inactive lifestyle.
Children aged 1-5 years are recommended to engage in 3 hours of physical activity per day, with less than 1 hour of static activity.
Children aged 6-17 years are recommended to engage in 1 hour of energetic activity per day, and regularly break up their screen and reading times.
Myopia control treatments only slow the progression of myopia and do not stop it.
There are 4 myopia control treatment options.
- Myopia control soft contact lenses
- Myopia control spectacles
- Atropine eye drops
Research has shown that all these treatments are equally effective in slowing myopia progression by about 50%. However, each child will have an individual response to treatment and need to be checked regularly to guarantee they are achieving the best results.
The best choice for your child will depend on their current prescription, eye shape, sports and lifestyle activities, and individual preferences. We will discuss the advantages and disadvantages of each choice and recommend a preferred option.
Specially designed rigid gas permeable lenses are worn overnight to gently reshape the cornea and can be effective for a range of prescriptions. Ortho-K lenses are removed in the morning and the reshaped cornea provides sharp vision throughout the day without the need for spectacles and contact lenses. Ortho-K lenses need to be worn nightly to maintain the new shape, otherwise the cornea will gradually return to its original curvature.
- No spectacle or contact lenses need to be worn through the day, great for contact and water sports
- Ortho-K lenses are handled at home in a safe environment, often under the supervision of a parent and so are less likely to be damaged or lost.
We have a range of disposable myopia control soft contact lenses that are worn through the daytime. These lenses have specially designed optical zones that change the focussing of light on the periphery of the retina and reduce eyeball growth.
Daily disposable – MiSight and NaturalVue multifocal lenses.
Monthly disposable – Mark’ennovy MYLO lenses.
- Good vision through the daytime with comfortable soft contact lenses.
- Daily lenses are simply discarded after one wear and require no cleaning or extra solutions.
- Daily lenses have the lowest rate of contact lens complications and are the safest contact lenses
- Mark’ennovy MYLO lenses are fully custom fitted and available for extremely high prescriptions (up to -15.0)
Two revolutionary spectacles lens designs are available with advanced peripheral defocus segments. The central area of the lens corrects the full prescription, and the peripheral segments alter the peripheral focussing to reduce eyeball growth.
Hoya MiYOSMART lenses uses Defocus Incorporated Multiple Segments (DIMS) technology.
Essilor Stellest lenses uses Highly Aspheric Lenslet Target (HALT) technology.
- Vision as sharp as standard single vision lenses
- Minimal adaptation
- Excellent vision for a wide range of prescriptions, especially high astigmatism
- Anti-reflective coating, impact resistant material with inbuilt UV protection
Atropine eye drops (1%) have been used for many decades in eyecare to dilate the pupil and to block the ability of the eye to focus. Research has shown that daily use atropine in low-dose concentrations (0.01% to 0.05%) can slow or stop the progression of myopia. It is suspected that atropine interacts with receptors at the back of the eye that control eye growth, but the exact mechanism of action is unknown.
Extensive clinical trials on children have shown little or no side effects or adverse reactions with low dose atropine. Side effects may include increased sensitivity to light, difficulty focussing when reading and can usually be eliminated by reducing the concentration. Adverse reactions are rare and include mild allergies, flushing of the skin and rapid and irregular pulse. These effects can be minimised by following the correct drop application technique.
Low dose atropine is considered safe for long term use for myopia control.
We supply a prescription for low-dose atropine and concentrations of 0.025% to 0.05% must be prepared and dispensed by a compounding pharmacist. In March 2022, Eikance (0.01% Atropine) was the first commercially prepared product approved for use in Australia.
- Simplicity – apply 1 drop into each eye at night
- Can be used in conjunction with current spectacles or contact lenses for daytime use
- Can be added to other myopic control treatments (Ortho-K) when additional myopia control is needed.