Causes of poor eyesight in young children

Causes of poor eyesight

• Myopia (Nearsightedness): Difficulty seeing distant objects clearly. Increasingly common due to prolonged near work (e.g., screen time, reading) and limited outdoor activity.
• Hyperopia (Farsightedness): Trouble focusing on close objects. Mild cases may go unnoticed but can cause eye strain or difficulty with tasks like reading.
• Astigmatism: Irregular curvature of the cornea or lens, causing distorted or blurry vision at all distances.
  • Cause: Often genetic, though exact triggers are unclear. Can be present at birth or develop early.
  • Prevalence: Up to 20-30% of children may have some degree of refractive error.

• Causes:
  • Strabismus: Misaligned eyes (e.g., one eye turns inward or outward), disrupting binocular vision.
  • Refractive amblyopia: Significant difference in prescription between the two eyes (anisometropia).
  • Deprivation amblyopia: Rare, caused by physical obstructions like cataracts blocking visual input.
• Impact: If untreated before age 7-8, permanent vision loss in the weaker eye can occur.
• Prevalence: Affects about 2-4% of children.

• Causes:
  • Muscle imbalance or neurological issues affecting eye coordination.
  • Can be genetic or triggered by high farsightedness, injury, or illness.
• Impact: Leads to double vision, poor depth perception, or amblyopia if untreated.
• Prevalence: Occurs in about 2-5% of children, often noticeable by age 3-4.

• Congenital Cataracts: Clouding of the eye’s lens at birth, blocking light. Caused by genetic mutations, maternal infections (e.g., rubella during pregnancy), or metabolic disorders.
• Congenital Glaucoma: Increased pressure in the eye due to improper drainage, leading to optic nerve damage. Symptoms include light sensitivity, tearing, or cloudy corneas.
• Retinopathy of Prematurity (ROP): Abnormal blood vessel growth in the retina, common in premature infants. Can lead to retinal detachment and blindness if severe.
• Nystagmus: Involuntary eye movements, often linked to genetic conditions or brain abnormalities, impairing clear vision.

• Albinism: Lack of pigment in the eyes can cause poor visual acuity, light sensitivity, and nystagmus.
• Retinitis Pigmentosa: Progressive retinal degeneration, rare in young children but can cause night blindness and peripheral vision loss.
• Color Vision Deficiency (Color Blindness): Usually genetic, more common in boys (affects ~8% of males vs. 0.5% of females). Difficulty distinguishing certain colors, like red-green.
• Optic Nerve Hypoplasia: Underdeveloped optic nerve, often linked to prenatal factors like maternal diabetes or alcohol use, causing partial vision loss.

• Congenital Infections: Rubella, cytomegalovirus (CMV), toxoplasmosis, or herpes simplex virus contracted in utero can harm the retina, optic nerve, or other structures.
• Uveitis: Inflammation of the eye’s middle layer, sometimes linked to autoimmune conditions like juvenile idiopathic arthritis.
• Conjunctivitis or Keratitis: Severe or untreated infections of the cornea or conjunctiva can scar tissue and impair vision.

• Corneal Abrasions: Scratches from accidents or foreign objects.
• Traumatic Brain Injury: Damage to visual processing areas in the brain, even if the eyes are structurally normal.
• Orbital Fractures: Rare, but can affect eye alignment or movement.

• Excessive Screen Time: Prolonged near work (phones, tablets, computers) is linked to myopia progression. Studies suggest children spending >2 hours daily on screens have higher risk.
• Limited Outdoor Time: Less exposure to natural light disrupts eye growth regulation, increasing myopia risk. Research shows 1-2 hours daily outdoors may protect against it.
• Poor Nutrition: Deficiencies in vitamin A (rare in developed countries) can cause night blindness or dry eyes. Malnutrition during pregnancy may affect fetal eye development.
• Inadequate Lighting: Chronic strain from reading or working in dim light can exacerbate refractive errors or cause discomfort.

• Diabetes: Though rare in young children, early-onset diabetes can cause diabetic retinopathy if uncontrolled.
• Neurological Disorders: Conditions like cerebral palsy or hydrocephalus may impair visual processing or eye movement control.
• Medications: Some drugs (e.g., corticosteroids) used for chronic conditions can increase glaucoma or cataract risk.

Risk Factors

• Family history: Genetic predisposition to refractive errors, strabismus, or congenital conditions.
• Prematurity or low birth weight: Higher risk of ROP or developmental issues.
• Maternal factors: Smoking, alcohol, or infections during pregnancy.
• Ethnicity: Myopia rates are higher in East Asian populations; some genetic disorders vary by ethnicity.

• Pediatric eye exams: Recommended at 6 months, 3 years, and before kindergarten (age 5-6). Earlier checks for high-risk infants (e.g., premature).
• Tests: Visual acuity charts, color vision tests, eye alignment checks, and retinal exams. Nonverbal children can be assessed with pictures or light responses.
• Red flags: Complaints of blurry vision, frequent headaches, eye rubbing, tilting head to see, or poor hand-eye coordination.

Management

• Glasses or Contacts: Correct refractive errors. Special lenses (e.g., orthokeratology) may slow myopia progression.
• Patching or Atropine Drops: Treat amblyopia by forcing use of the weaker eye.
• Surgery: For cataracts, strabismus, or severe glaucoma. ROP may require laser therapy.
• Vision Therapy: Exercises to improve eye coordination or focus.
• Lifestyle Changes: Limit screen time, encourage outdoor play (1-2 hours daily), ensure proper lighting.

Prevention Tips

• Schedule regular eye exams, even without obvious symptoms.
• Balance screen time with outdoor activities.
• Ensure a nutrient-rich diet (e.g., leafy greens, fish for omega-3s).
• Protect eyes from injury with safety gear during sports.