What is Myopia?
Myopia (also called nearsightedness) is the most common cause of impaired vision in people under age 40. In recent years, its prevalence is growing at an alarming rate. Globally, research suggests that in the year 2000, roughly 25 percent of the world’s population was nearsighted but by the year 2050, it’s expected that roughly half the people on the planet will be myopic.
If you are myopic or nearsighted, you will have difficulty reading road signs and seeing distant objects clearly, but will be able to see well for close-up tasks such as reading and computer use.
Other signs and symptoms of myopia include squinting, eye strain, and headaches. Fatigued when driving or playing sports also can be a symptom of uncorrected nearsightedness.
If you experience these signs or symptoms while wearing your glasses or contact lenses, schedule an eye exam with your optometrist to see if you need a stronger prescription.
Causes of nearsightedness
Myopia occurs when the eyeball is too long, relative to the focusing power of the cornea and lens of the eye. This causes light rays to focus at a point in front of the retina, rather than directly on its surface.
Nearsightedness can also be caused by the cornea and/or lens being too curved for the length of the eyeball. In some cases, myopia occurs due to a combination of these factors.
Myopia typically begins in childhood, and you may have a higher risk if your parents are nearsighted. In most cases, nearsightedness stabilizes in early adulthood but sometimes it continues to progress with age.
Treatment for nearsightedness
There is no best method for correcting myopia. The most appropriate correction for you depends on your eyes and your lifestyle. Discuss your lifestyle with your ophthalmologist. Together, you can decide which correction may be most effective for you.
Eyeglasses or contact lenses are the most common methods of correcting myopia symptoms. They work by refocusing light rays on the retina, compensating for the shape of your eye. Eyeglasses can also help protect your eyes from harmful ultraviolet (UV) light rays. A special lens coating that screens out UV light is available.
In many cases, people may choose to correct myopia with LASIK or another form of refractive surgery. These surgical procedures improve your vision by reshaping the cornea. The reshaped cornea focuses light properly onto the retina.
Refractive surgeries for myopia include:
- SMILE, and
- Refractive lens exchange.
You may have heard of a process called orthokeratology to treat myopia. It uses a series of hard contact lenses to slowly flatten the cornea and reduce myopia. It involves sleeping in hard contact lenses every night. This has been associated with an elevated risk of serious, vision-threatening eye infections. Vision improvement is temporary. After you stop using the lenses, your cornea goes back to its original shape, and myopia returns.