Myopia (Nearsightedness) Causes, Symptoms, Diagnosis and Treatment

What Is Myopia (Nearsightedness)?

Myopia, commonly known as nearsightedness, is a refractive error of the eyes where close objects appear clear but distant objects appear blurry. It is one of the most prevalent vision conditions globally, affecting approximately 30% of the world's population.

What Causes Myopia?

Myopia occurs when the eyeballs are slightly longer than normal or the cornea is too curved. This causes light entering the eye to focus in front of the retina instead of directly on it. As a result, distant objects appear blurred.

Some of the key factors that contribute to myopia include:

• Genetics - Research shows that myopia has a hereditary component. Children with one or two nearsighted parents are more likely to develop the condition.
• Environmental factors - Increased near work activities like reading, writing, computer use can increase the chances of developing myopia.
• Low light exposure - Spending less time outdoors may be a risk factor for nearsightedness.

Signs and Symptoms

The primary sign of myopia is blurred vision of distant objects. Other signs and symptoms include:

• Headaches and eyestrain from squinting or eye overuse
• Difficulty seeing faraway objects like road signs or the board in school
• Needing to sit near the television or hold books closer to read
• Frequent eye rubbing

Diagnosing Myopia

A comprehensive eye exam by an optometrist or ophthalmologist can diagnose myopia. Here are some tests that may be conducted:

• Visual acuity test - This checks your vision from a standard distance.
• Refraction test - This determines your eyeglass prescription.
• Retinoscopy - A tool is used to shine a light in your eye to assess refractive errors.
• Eye health exam - The doctor examines the eyes for signs of health issues.

Based on the results of the eye exam, the type and degree of myopia can be determined. Myopia is classified into three categories based on severity:

• Low myopia - Between -0.50 to -3.00 diopters
• Moderate myopia - Between -3.25 to -6.00 diopters
• High myopia - -6.00 diopters or greater

Treatment Options for Myopia

Here are some of the treatment options available to correct nearsighted vision:

Eyeglasses

Wearing corrective eyeglasses is the simplest and most common treatment option. Single-vision lenses or bifocals can help correct myopic vision. Anti-reflective and scratch-resistant coatings also help optimize visual clarity.

Contact Lenses

Soft contact lenses that sit directly on the cornea can also correct myopia. Contact lenses provide better peripheral vision compared to eyeglasses. They must be properly fitted by an eye doctor and cared for to avoid infections.

Orthokeratology

This involves wearing rigid gas permeable lenses temporarily at night to gradually reshape the cornea and reduce myopia. It can slow the progression of nearsightedness in children.

Refractive Surgery

For people with severe myopia who don't want to wear glasses or contacts, refractive surgeries like LASIK can reshape the cornea and permanently correct vision. There are risks involved, so consult an ophthalmologist.

Preventing Progression of Myopia

While myopia cannot be prevented completely, the following tips may help slow its progression:

Limit Near Work

Restrict close activities like reading, computer use and video games to short durations with frequent breaks. Practicing the 20-20-20 rule (looking away every 20 minutes for 20 seconds at something 20 feet away) can help reduce eyestrain.

Increase Outdoor Time

Spending more time outdoors especially during childhood can discourage myopia progression. Exposure to natural daylight regulates hormones linked to nearsightedness.

Healthy Diet

Eating a balanced diet rich in fruits, vegetables and fatty acids found in fish and nuts may support healthy eyesight development in children.

Take Frequent Breaks

Resting your eyes regularly prevents overuse. Do eye stretches, palm massages and focus exercises to relax the eye muscles.

Get Regular Eye Exams

Have your eyes examined once every 1-2 years to monitor for any changes in vision or ocular health issues. Early intervention can help control advancing myopia.

Risk Factors of High Myopia

While most myopia cases are mild, high myopia of -6 diopters or greater can increase the risk of certain eye disorders like:

• Cataracts - Clouding of the eye's natural lens
• Glaucoma - Damage to the optic nerve
• Retinal detachment - Separation of the retina from underlying tissue
• Myopic macular degeneration - Breakdown of the macula portion of the retina

The structural changes in highly myopic eyes may also lead to vision impairment and blindness if not managed properly. Hence, people with high myopia must get comprehensive eye exams done regularly.

Myopia Doesn't Have to Limit You

While myopia is a common vision problem worldwide, it can be effectively managed with solutions like eyeglasses, contact lenses and eye exercises. Catching it early and sticking to your treatment plan helps keep your eyes healthy and your vision clear both for near and far.

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.