Question

What are types of myopia? Discuss the measures to prevent progression of myopia.

Hint:

Early intervention and lifestyle changes, such as increased outdoor activity and limiting near work, are essential in preventing the progression of myopia, especially in children.

Answer 1

Myopia, or nearsightedness, is a refractive error where distant objects appear blurry while near objects can be seen clearly. The condition occurs when the light entering the eye focuses in front of the retina, rather than directly on it.

Step 1: Types of Myopia:
1. Simple Myopia: This is the most common form, typically developing in childhood or adolescence. It is caused by an elongated eyeball or excessive curvature of the cornea, resulting in light focusing in front of the retina.
2. Pathological Myopia: Also known as degenerative myopia, this type is characterized by excessive elongation of the eyeball and can lead to retinal degeneration and other serious ocular complications. It typically worsens with age.
3. Youth-onset Myopia: This refers to myopia that develops during childhood or adolescence and tends to stabilize after the individual reaches adulthood. It is typically less severe than pathological myopia.
4. Induced Myopia: This form of myopia is caused by external factors such as prolonged near work, use of certain medications, or eye surgery.

Step 2: Measures to Prevent Progression of Myopia:
1. Control of Near Work: Limiting prolonged near work (such as reading or screen time) can help reduce the strain on the eyes. The "20-20-20 rule" suggests taking a break every 20 minutes by looking at an object 20 feet away for 20 seconds.
2. Outdoor Activity: Studies have shown that spending time outdoors in natural light can slow the progression of myopia in children. This may be due to the effects of bright light on retinal growth.
3. Corrective Lenses: Wearing prescription glasses or contact lenses helps manage the symptoms of myopia, preventing strain on the eye and controlling the condition. Orthokeratology (Ortho-K) lenses, which reshape the cornea, may also be used to control myopia progression.
4. Pharmacological Interventions: Low-dose atropine eye drops have been found to reduce the rate of myopia progression in children. These drops are typically used at night and help relax the eye's focusing mechanism.
5. Myopia Control Lenses: Specially designed glasses or contact lenses, such as bifocal or progressive lenses, can help slow the progression of myopia by reducing eye strain during near tasks.