Understanding Myopia (Nearsightedness) - Causes, Symptoms and Treatment

Understanding Myopia (Nearsightedness) - Causes, Symptoms, Diagnosis and Treatment

Myopia, commonly known as nearsightedness or short-sightedness, is a refractive error of the eyes that causes blurry distance vision. It is one of the most prevalent vision disorders globally, affecting around 30% of the population. For those with myopia, close objects are seen clearly but distant objects appear out of focus.

What Causes Myopia?

Myopia occurs when the shape of the eye causes light rays to focus in front of the retina rather than directly on it. This causes distant objects to appear blurred while close objects come into sharp focus.

People are generally born with one of two eye shapes that contribute to myopia development:

• Axial myopia - where the eyeball is too long from front to back
• Refractive myopia - where the cornea has too much curvature

Genetics play a major role in which eye shape you are born with. Myopia tends to run in families. Environmental factors like excessive near work can also influence eye growth and cause axial length to increase over time, leading to myopia progression.

Common Symptoms of Myopia

The primary symptom of myopia is blurry, distorted vision at a distance. Common signs of nearsightedness include:

• Difficulty clearly seeing faraway objects like road signs, movies, presentations
• Squinting, eye strain or headaches trying to focus on distant objects
• Need to sit near the front of the classroom or movie theater to see
• Vision improves when objects are moved closer
• Eyestrain or headaches after prolonged reading, computer work, etc.

Symptoms often first develop in childhood as the eyes grow. They tend to worsen gradually over time as the myopia increases. People may develop related issues like eye fatigue, poor night vision, problems perceiving depth, and increased risk of retinal problems.

Getting an Accurate Myopia Diagnosis

If you are experiencing blurred distant vision, it is important to schedule an eye exam by an optometrist or ophthalmologist. They will perform a series of comprehensive tests to evaluate your vision and determine an accurate prescription.

Diagnostic tests for myopia include:

• Visual acuity - reading an eye chart to measure sharpness of vision at various distances
• Refraction - identifying focusing errors by testing vision through various corrective lenses
• Eye alignment - checking how the eyes work together as a team
• Pupil dilation - enlarging the pupils with eye drops to examine the retina
• Tonometry - measuring fluid pressure inside the eye (intraocular pressure)

These tests help determine your degree of nearsightedness, which is measured in diopters. Mild myopia usually ranges from -0.50 to -2.75 diopters, moderate from -3.00 to -5.75 diopters, and severe higher than -6.00 diopters.

Treatment Options for Myopia

While there is no outright “cure” for nearsightedness, several effective treatment options can correct blurred vision and help you see clearly. The main treatment approaches include:

Corrective Lenses

Eyeglasses or contact lenses are the simplest way to correct myopic vision. Concave lenses help bend light rays properly onto the retina to bring faraway objects into clear focus. Contact lenses provide added convenience by enabling clearer vision without having to wear glasses.

Refractive Eye Surgery

Surgical procedures like LASIK and PRK use an excimer laser to reshape the cornea and permanently correct myopic vision. This can reduce or eliminate the need for glasses or contacts. However, potential complications include dry eyes, glares, halos, and in rare cases permanent vision loss.

Orthokeratology

Ortho-k involves wearing specialized gas permeable contact lenses overnight to gradually reshape the cornea. This temporarily corrects vision during the day without contacts or glasses. Disadvantages include nightly lens wear and risk of eye infections.

Myopia Control

For children still developing myopia, methods like specialized contact lenses and eye drops aim to slow its progression. Though not an outright cure, controlling myopia progression helps maintain better vision long-term.

Preventing Myopia Progression in Children

Since myopia often develops and worsens during childhood, preventing progression is key for maintaining better vision over time. Recommended prevention strategies include:

• Limiting close-up work and increasing outdoor time
• Taking regular vision breaks during near tasks
• Maintaining proper posture and lighting when reading
• Eating a healthy diet rich in antioxidants
• Wearing prescribed myopia-control contact lenses
• Trying evidence-based eye drops like low-dose atropine

Early intervention is ideal, as slowing myopia progression becomes more difficult with age. Consulting an optometrist knowledgeable in myopia management can help guide proper prevention strategies.

Living with Myopia as an Adult

If you already have developed significant myopia, the keys are managing it effectively and having regular eye exams to monitor for any associated risks.

Be sure to wear properly corrected and fitted eyeglasses or prescription contacts any time clear vision is needed. Have your vision prescription updated annually or if vision changes are noticed.

Make ocular health a priority by getting a dilated eye exam every 1-2 years. Those with high myopia or retinal issues may need monitoring every 6-12 months. Report any new floaters, flashes of light, or significant vision changes to your eyecare provider right away.

Practice healthy vision habits like taking screen breaks, maintaining proper lighting, wearing sunglasses outdoors, eating eye-friendly nutrition, and avoiding smoking to keep your eyes as healthy as possible.

Conclusion

Myopia is a common vision disorder, but its symptoms can be effectively corrected with glasses, contacts, or surgery. Slowing progression from an early age is key. Practicing healthy vision habits and getting regular eye exams helps ensure people with myopia can enjoy clear, comfortable vision for life.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.