Myopia

Myopia, commonly known as nearsightedness, is a common refractive error of the eye where distant objects appear blurry while close objects can be seen clearly. This condition occurs when the eyeball is too long or the cornea is too curved, causing light entering the eye to focus in front of the retina rather than directly on it.

Key Features

1. Blurry Distance Vision: The hallmark symptom of myopia is difficulty seeing distant objects clearly. Near vision, such as reading or working on a computer, is typically unaffected.
2. Onset and Progression: Myopia often develops in childhood and can progress through adolescence. It tends to stabilize in early adulthood.
3. Prevalence: Myopia is one of the most common vision problems worldwide, affecting a significant portion of the population.

Symptoms

• Blurry vision when looking at distant objects
• Squinting to see clearly
• Eye strain or headaches from prolonged visual tasks
• Difficulty seeing while driving, especially at night (night myopia)

Causes

Myopia results from a mismatch between the focusing power of the eye and its length. Factors contributing to myopia include:

• Genetics: A family history of myopia increases the likelihood of developing the condition.
• Environmental Factors: Extended periods of near work (e.g., reading, using computers) and limited time spent outdoors have been associated with the development and progression of myopia.
• Structural Abnormalities: An elongated eyeball or a steeply curved cornea causes light to focus in front of the retina.

Diagnosis

Diagnosing myopia involves a comprehensive eye examination, which may include:

1. Visual Acuity Test: To measure the clarity of vision at various distances.
2. Retinoscopy: To observe the reflection of light from the retina, helping determine the degree of refractive error.
3. Refraction Test: Using a phoropter or autorefractor to determine the appropriate lens prescription for correcting vision.

Treatment

The goal of myopia treatment is to correct the refractive error and improve distance vision. Options include:

1. Eyeglasses: The most common and simplest method for correcting myopia. Lenses with a negative diopter value (minus lenses) correct the focus.
2. Contact Lenses: Provide a wider field of view and are suitable for those who prefer not to wear glasses. Various types are available, including soft, rigid gas-permeable, and extended-wear lenses.
3. Refractive Surgery: Surgical options aim to reshape the cornea and include procedures such as:
   • LASIK (Laser-Assisted in Situ Keratomileusis): A laser reshapes the cornea to correct the refractive error.
   • PRK (Photorefractive Keratectomy): A laser removes a small amount of corneal tissue to flatten the cornea.
   • SMILE (Small Incision Lenticule Extraction): A minimally invasive procedure that reshapes the cornea by removing a small piece of tissue.
4. Orthokeratology (Ortho-K): Specially designed rigid contact lenses are worn overnight to temporarily reshape the cornea, improving vision during the day without the need for glasses or contact lenses.

Managing Myopia Progression

For children and adolescents, managing myopia progression is essential to reduce the risk of high myopia and associated complications. Strategies include:

1. Atropine Eye Drops: Low-dose atropine drops can slow the progression of myopia in children.
2. Multifocal Contact Lenses or Glasses: Designed to reduce eye strain and slow myopia progression.
3. Increased Outdoor Time: Encouraging children to spend more time outdoors, which has been associated with a slower progression of myopia.
4. Limit Near Work: Reducing prolonged near work and encouraging regular breaks during close-up activities.

Complications

Severe or high myopia increases the risk of several eye complications, including:

• Retinal detachment
• Glaucoma
• Cataracts
• Myopic maculopathy (degeneration of the central retina)

Conclusion

Myopia is a common vision condition where distant objects appear blurry due to the eye's inability to focus light directly on the retina. It can be diagnosed through a comprehensive eye exam and treated with glasses, contact lenses, or refractive surgery. Managing myopia progression in children is crucial to prevent severe complications. Regular eye exams are important to monitor vision changes and maintain eye health. If you experience symptoms of myopia or have concerns about your vision, consult an eye care professional for evaluation and appropriate management