Do you squint when looking at distant objects? That can be a sign of myopia as it can lead to squinting.
Of course, only an eye doctor can say for sure if you have a problem with your eyesight, so schedule a visit to an eye doctor in Dubai to get a proper diagnosis. The sooner a vision problem is detected, the sooner it can be treated.
If your doctor says you have myopia, read on. Below is a discussion of what myopia is and how it can be treated.
What Is Myopia?
Myopia is a refractive error. It’s called nearsightedness because having ‘near sight’ is its defining condition. Essentially, someone with myopia sees nearby objects very well. However, they have trouble discerning things that are farther away.
When you have myopia, you can see what’s on your mobile phone screen or the text on the magazine in your hands and easily recognise a friend seated at a table or a chair a couple of metres away from you in a restaurant. However, you cannot read the signs on the road, and you probably easily overlook friends and acquaintances standing just 10 metres in front of you.
Their far-sight problem is why people with myopia tend to squint when looking at things in the distance. Squinting diminishes the pupil’s size, reducing the amount or intensity of light coming into the eyes. This enhances focus and allows nearsighted people to see a faraway object.
How the Eyes See?
Understanding refractive errors like myopia requires learning how the eyes work to provide vision. To see something, light needs to bounce off that object and enter your eyes. This is why you can’t see well in the dark.
The cornea and the lens direct the light rays carrying information about an object to the back of your eyes. The cornea is the transparent, convex dome on the eye surface, while the lens is a convex disk that sits behind the iris. The cornea and the lens both refract or bend light, with the former having a refractive power of around +43 diopters while the latter has a light-bending power of around 22 diopters.
The refracted light rays land on or are projected onto the retina. The retina, which is essentially a layer of photoreceptor and glial cells, transmits the image it receives as electrical and chemical signals for the brain to perceive — after which what you see in front of you finally registers.
All these steps take place in a brief moment. Visual information takes only around 13 milliseconds to be received and perceived.
What Causes the Refractive Error Leading to Myopia?
The light carrying image information must hit the retina directly for a clear image to be formed and subsequently perceived. This does not happen if you have myopia.
Myopia causes the refracted or bent light to converge or focus in front of the retina instead of on the retina itself. Thus, the retina transmits a blurry image to the brain.
What causes this condition? It’s usually one or both of the following things:
The cornea is too domed or convex and has a steep or sharp curve. Therefore, the light rays that enter through it are bent too much, converging much earlier than ideal — i.e., in front of the retina.
The eyeball is too long or too oval. This translates to a longer distance between the cornea and the back of the eyes (i.e., axial length). Thus, the converging light rays fall short of the retina.
If an excessively curved cornea is the cause of myopia, it is called refractive myopia. If it’s a too-long eyeball, it’s axial myopia.
How Is Myopia Treated?
Myopic eyesight can be managed and corrected. The following are some of the strategies that can be used:
1. Eyeglasses
Eyeglasses are easy to use and accessible, so they’re the default tool for managing myopia. Your eye doctor needs to conduct eye examinations before prescribing eyeglasses. They need to gauge your exact degree of nearsightedness to ensure they can order glasses that will precisely compensate for the distance vision you lack.
2. Contact Lenses
Contact lenses are an alternative to eyeglasses. They do what eyeglasses do: compensate for missing far sight.
Some people report they get sharper and wider distance vision with contact lenses than with eyeglasses; others simply prefer the former because they find eyeglass frames cumbersome.
However, contact lenses require more effort than eyeglasses to maintain.
3. Ortho-K
Ortho-K stands for orthokeratology. This corrective procedure entails wearing contact lenses not to compensate for distance vision but to shape the cornea so it can refract light correctly.
Ortho-K treatment requires measuring the eyes and mapping the cornea. Once that’s done, custom-fitted contact lenses are created. You must wear them to bed, overnight.
While you sleep, they will temporarily flatten your cornea. The following day, the shallower cornea resulting from the overnight shaping will translate to refracted light rays converging farther back into the eyes and hitting the retina instead of focusing in front of it.
For children with myopia, paediatric Ortho-K is an excellent myopia management strategy. It is non-invasive, is effective, and doesn’t require children to wear eyeglasses or contact lenses while in school or performing their daily activities.
4. Refractive Surgery
Refractive surgery involves a surgeon using a scalpel, a laser or some other tool to reshape the cornea.
Specific types include laser-assisted in situ keratomileusis (LASIK), laser-assisted subepithelial keratectomy (LASEK), photorefractive keratectomy (PRK), radial keratotomy (RK), and automated lamellar keratoplasty (ALK).
5. Intracorneal Rings
Intracorneal rings are thin rings implanted into the cornea to flatten it and improve distance vision in patients with myopia.
6. Phakic Intraocular Lens
Phakic intraocular lens involves implanting a lens into the eyes to compensate for refractive errors.
7. Therapy
Vision therapy or eye exercises may be indicated if the refraction or focus error is due to weak eye muscles.
Managing Myopia
Myopia or nearsightedness occurs when light rays entering the eye converge or focus in front of the retina instead of on the retina. This usually happens when the cornea is too steep, or the eyeball is too long.
Myopia can be corrected through various strategies, including eyeglasses, contact lenses, ortho-K, surgery, corneal ring implants, lens implants, and vision therapy.
If you’re nearsighted, ask your doctor which solution best suits your condition.
लेखक
