Myopia is a common eye disease in which the eye focuses on the image before it reaches the retina where it usually does, producing a blurred image.
Myopia can be divided into two broad categories: refractive and axial.
Refractive myopia: is due to the eye’s abnormally high focusing power.
Axial myopia: Axial myopia, the most common cause, is due to the eye’s excessive axial length, measured from the cornea to the back of the eye.
Studies show that the eye is actively managing axial length and optical power to maintain a clear image during growth and development. If this autoregulatory process is poorly controlled, the eye can elongate disproportionately, creating axial myopia.
The process and progression of myopia follows a typical pattern with normal vision at a young age. From school age onwards, myopic displacement and a rapid increase in myopia begin and continue until late adolescence. High myopia is associated with a significant increased risk of retinal problems, including retinal detachment, glaucoma and cataracts at an early age. These eye diseases increase the risk of severe visual impairment.
Epidemiology
Myopia is an extremely common eye disease worldwide.
The percentage of myopes in Asian populations varies from 37% to 60%.
It is estimated that myopia affects 25 to 33 % of adults in the United States and Western Europe, with a 66% increase in the prevalence of myopia over a 30-year period.
Risk Factors
Ethnicity
Ethnicity has been studied as a risk factor for myopia progression.
Internationally, the annual myopic progression rate for Singapore has been reported at -0.80 diopters per year, while European Caucasian ethnicities report progression rates closer to -0.50 diopters per year. Studies have also shown that Caucasians take the longest to stabilize (16.32 years).
Age
The strongest risk factor for myopia progression is having myopia at a young age, particularly under the age of 6 or 7. Not only is the final myopia greater in this group, but also the progression and lengthening of the axial length are faster.
Parental myopia
Several studies have shown that parental myopia, even in a single parent, increases the risk of myopia in children. It has even been reported that there is a more than six-fold increased risk of developing myopia if both parents are myopic.
Parental myopia is not only a risk factor for myopia, but also for myopia progression in children.
Gender
There is conflicting evidence when assessing sexual predisposition to myopia. The COMET study showed that there was no difference between men and women…
Environmental factors
Several studies have been carried out to examine various environmental or non-genetic factors that could play a role in the development of myopia. The amount of close work, such as reading or using portable electronic devices, done by a child during the day had little or no association.
Numerous studies have shown that time spent outdoors is protectively associated with myopia.
The results showed that increasing the amount of time spent outdoors reduced the risk of developing myopia by 2% for every hour spent outdoors per week. This offers a practical solution for myopia prevention, with all the many other health benefits associated with outdoor activities.
Treatments
People with myopia have several options for regaining clear vision at a distance:
1. Glasses
For most people with myopia, glasses are the first solution offered, given the young age when diagnosed. Depending on the degree of myopia, you may only need to wear glasses for certain activities, such as watching a movie or driving a car. Or, if you’re very short-sighted, you may need to wear them all the time.
2. Contact lenses
For some people, contact lenses offer clearer vision and a wider field of vision than glasses. However, because contact lenses are worn directly on the eyes, they require proper assessment and care to protect eye health from serious infections that can result from lens wear.
3. Laser vision correction
Laser procedures such as Femtolasik are definitive solutions for adult myopia.
A laser beam of light reshapes the cornea to compensate for myopia.
The degree of myopia that LASIK can correct can be up to -8 diopters, but is limited by the amount of corneal tissue that can be safely removed. To do this, part of the outer corneal surface is lifted and folded back to expose the inner tissue. A laser then removes the precise amount of corneal tissue needed to reshape the eye. The outer tissue flap is then moved back into position to heal.
Other refractive eye surgeries:
People whose corneas are too thin for laser procedures can benefit from surgical correction of their myopia.
Our ophthalmologists are able to implant small lenses with the desired optical correction in their eyes. The implant can be placed just in front of the natural lens (phakic intraocular implant), or the implant can replace the natural lens (clear lens extraction with intraocular lens implantation).
If you suffer from myopia, you can benefit from a variety of options to correct your vision problem. Our ophthalmologists at Oculus Eye Clinics will help you choose the treatment that best suits your visual needs and lifestyle.