Myopia

What is Myopia?

Myopia, also known as short-sightedness, is a common refractive error wherein images images focus infront of the retina due to elongation of the eye's axial length, causing distant objects to appear blurred while close-up ones remain clear.

Myopia

Myopia can be classified into varying degrees of severity, with high myopia exceeding 5 diopters (-5.00), and low myopia typically below 3 diopters (-3.00). In children, myopia tends to advance over time, with prescriptions generally stabilising in their 20s.

Risk Factors of Myopia

Factor such as genetics, ethnicity, age and environmental factors such as excessive near work and/or lack of outdoor activity can contribute to the development and progression of myopia.

Symptoms of Myopia

Trouble seeing things far away

Myopia patients have a longer eyeball than a person with no myopia, which causes the light that is entering the eye to focus in front of the retina instead of directly on it. Hence, objects that are far away are not focused sharply onto the retina leading to a blurred vision when looking at things far away.

Needing to squint to see clearer

Myopic patients may squint to see things clearly, as it reduces the amount of unfocused light reaching the retina, thereby improving the patient's vision. Essentially. squinting alters the path of incoming light rates, compensating for the refractive error of the eye and allowing for better focus on objects, particularly those at a distance.

Complications of Myopia

1. Degenerative changes

In patients with high levels of myopia, they are more susceptible to degenerative changes in the retina, such as retinal detachment, macular degeneration and choroidal neovascularization.

2. Increased risk of eye conditions

Myopia is associated with higher risks of developing various eye conditions including glaucomas, cataracts, myopic maculopathy and also retinal detachment.

Studies indicate that the risk of certain eye conditions is elevated in correlation with the severity of myopia. Specifically, individuals with varying degrees of myopia face increased risks compared to those without myopia. For instance, the risk of glaucoma is amplified by a factor of 2.2 to 3.3 times. Similarly, the risk of cataracts rises by a factor of 2.1 to 5.5 times, while for retinal detachment, the risk of myopic maculopathy is heightened by a factor of 2.2 to 126.8 times.

How to manage Myopia?

1. Glasses

The most common way for people to correct myopia is with eyeglasses with single vision lenses which makes distance vision clearer. The frequency of wearing eyeglasses depends on the level of vision correction required. You might wear them on a daily basis or only when distance vision is necessary. For instance, glasses may be needed solely for driving.

In the case of children with myopia, glasses might only be required for specific activities like playing sports, watching movies, or viewing the whiteboard. Conversely, some individuals may need to wear glasses continuously for clear vision throughout the day.

Myopia control glasses, helps to both control and correct myopia with a special type of lens design with 2 zones, the “defocus” zone and “focus zone”. The “defocus” zone helps with slowing down myopia progression and the “focus” zone has the prescription which helps in seeing far and providing clear vision.

In Singapore, there are two main types of spectacle lenses which have been shown to be effective in reducing the progression of myopia. These lenses are Hoya Miyosmart lenses as well as Essilor Stellest lenses which both boasts 60% and higher effectiveness in controling the progression of myopia in children.

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2. Contact Lenses

Certain individuals may discover that their distant vision appears sharper and offers a wider field of view when using contact lenses. However, it's important to note that contact lenses demand more care to ensure cleanliness. Consult your optometrist to determine the most suitable type of contact lenses based on your level of myopia and other refractive issues.

Orthokeratology, also known as Ortho-k, is the use of specifically designed and fitted rigid gas permeable lenses that would help to temporarily reshape the cornea to slow down the progression of myopia. These lenses work by reshaping the cornea or altering the way light enters the eye, which can help reduce the elongation of the eyeball associated with myopia progression.

orthok-on-eye

For soft contact lenses, there are a growing number of solutions that are being used for children to control their myopia progression while correcting them. Some of these products are MiSight 1 Day, Abiliti 1-Day as well as Bloom 1-Day.

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