Myopia

Myopia is a common eye condition that is becoming more widespread. Objects up close are in focus while objects in the distance appear blurry.

Myopia is reaching epidemic proportions as young people spend more time focusing on close work on their numerous digital devices. Once myopia starts in childhood, it usually gets worse and worse every year until the age of about 20-25.

Unfortunately, the worse myopia gets, the higher the risk of future eye diseases.

Luckily, research has shown that certain myopia treatment strategies can delay or slow down myopia – which means less chance of getting an eye disease in the future. Dr Jim Kokkinakis explains:

What is myopia?

Myopia, also known as short sightedness and near sightedness, is an eye condition which is reaching epidemic proportions worldwide. It causes blurry distance vision, while objects up close remain clear and in focus. This most often happens because the eyeball grows longer than normal.

Myopia definition

The definition of myopia is having a refractive error (or glasses prescription) of at least -0.50D in one or both eyes.

The opposite of myopia is hyperopia or hypermetropia (also known as long sightedness), which means having a refractive error of +0.50D or more. Hyperopia can cause blurry reading or close vision, and higher levels of hyperopia can also cause blurry distance vision.

Optometrists distinguish between myopia and hyperopia during an eye examination. Believe it or not, sometimes one condition may mimic the other and several specialised tests may be required. Simply reading letters on a chart at a GP’s office or at a school vision screening does not give any information or diagnosis about what someone’s eye condition is.

High myopia

The definition of high myopia has varied over the years, however it is generally considered to be high when the spectacle prescription reaches -5.00D or greater in one or both eyes. The higher the amount of myopia, the higher the risk of eye diseases such as glaucoma, cataract, macular disease and retinal detachment. You can read more on our dedicated ‘Myopia and Eye Disease’ page.

Myopia causes

Myopia generally develops in the childhood or teenage years and this can be influenced by a combination of genetics, environment and other individual visual characteristics. Some children are more at risk of developing myopia compared to others. Having any of the following risk factors puts a child at an increased risk of developing myopia:

Age: The earlier myopia begins the quicker the progression

Ethnic Background: Myopia is much more common in children of East Asian descent

Family History: Having 1 myopic parent = 3x higher risk (2 parents = 6x risk)

Refractive Error: Children should normally be long sighted (hyperopia).

Time Spent Outdoors: Less than 1.5 hours per day increases myopia risk

Time Spent on Near Work: More than 2.5 hours per day increases myopia risk

Why does myopia get worse every year?

Once myopia starts, it generally gets worse as time goes on. If it gets worse at a fast rate, there is more chance of ending up with high myopia. There are ways to slow down the progression of this eye condition. These are discussed under Myopia Control and include low-dose atropine treatment, orthokeratology contact lenses, multifocal contact lenses and multifocal / bifocal glasses.

Effects of myopia

Unfortunately, myopia (even a very low amount) increases the risk of many eye diseases. The higher the myopia, the higher the risk.
Here are some examples of the increased risk, compared to someone that does not have myopia:

Amount of Myopia	Retinal Detachment Risk	Glaucoma Risk	Cataract Risk	Macula Disease
-1.00 to -3.00	3.1x higher risk	4x higher risk	2.1x higher risk	2.2x higher risk
-1.00 to -3.00	9x higher risk	4x higher risk	3.1x higher risk	10-40x higher risk
-1.00 to -3.00	21.5x higher risk	4x higher risk	5.5x higher risk	127x higher risk
-9.00 or greater	44.2x higher risk	4x higher risk	5.5x higher risk	349x higher risk

The good news is, there are simple strategies that can delay the onset of myopia and also slow it down once it starts. Delaying or preventing myopia can reduce the risk of getting high myopia, and thus reduce the risk of future eye diseases.

Atropine eye drops and other myopia treatments

A pair of glasses can make the distance vision clear, but glasses alone do not stop the myopia from getting worse. Myopia control treatments aim to slow down or stop myopia from getting worse. Atropine eye drops, orthokeratology and multifocal contact lenses are all options to slow progress of this condition. Based on the latest research, the following treatments can slow down myopia:

Treatment	Effect on slowing down myopia
Orthokeratology (ortho-k) lenses	30 – 56%
Multifocal soft contact lenses	25 – 72%
Atropine eye drops	34 – 96%
Executive Bifocal glasses	39 – 51%
Progressive glasses	11 – 33%

To get a better idea of much these strategies can slow your (or your child’s) myopia, you can use a Myopia Calculator. By entering your child’s age and spectacle prescription, you can get an idea how short-sighted they will be at a certain age with or without various myopia control strategies.

Depending on each child’s individual characteristics, optometrists at The Eye Practice can customise a treatment plan to help achieve the maximum myopia control effect possible.