Amblyopia (lazy eye) is a childhood condition in which the vision in one eye does not develop properly. It occurs when the brain favours one eye over the other, often caused by eye misalignment (strabismus), uncorrected refractive errors (farsightedness/nearsightedness), or deprivation (cataracts). Over time, this can lead to reduced vision in the affected eye. Read on to learn about the causes, symptoms and treatment of amblyopia.
Types of Amblyopia
Lazy eye is usually classified based on its underlying cause. So, the type of amblyopia one has depends on what caused this condition.
1. Strabismic Amblyopia
This is one of the most common types of amblyopia. It occurs when the eyes are misaligned. The misalignment causes the brain to receive two different images as a result, the brain begins to ignore the image from one eye to avoid double vision. Over time, this leads to reduced vision in the affected eye.
2. Refractive Amblyopia
This type develops due to uncorrected refractive errors and is classified into three subtypes.
– Anisometropic amblyopia
It occurs when there is a significant difference in refractive error between the eyes, leading the brain to favour the clearer image and suppress the blurrier one. This can result in reduced vision in one eye and poor depth perception
– Ametropic amblyopia
This occurs when both eyes have high, uncorrected refractive errors, such as hyperopia, myopia or astigmatism. As a result, vision is blurred in both eyes during early visual development. Since the brain receives consistently unclear images from both eyes, normal visual development is impaired.
– Meridional amblyopia
This is caused by uncorrected astigmatism, wherein one or both eyes are astigmatic. Over time, this can affect the vision.
3. Deprivation (stimulus deprivation) Amblyopia
A rare but severe type of amblyopia, this condition develops when something blocks light from entering the eye during early childhood. It can be caused by congenital cataract or drooping eyelid (ptosis).
Who is at Risk of Amblyopia?
Many factors can increase the risk of amblyopia among certain children, including:
- Premature birth or low birth weight
Babies born early or with a lower-than-average birth weight are at higher risk of developing visual development problems, such as amblyopia - Family history of eye conditions
Children with a family history of lazy eye, squint or cataracts are more likely to develop the condition - Developmental or neurological conditions
Children with developmental delays or neurological conditions may be at a higher risk due difficulties with visual development
Signs and Symptoms of Amblyopia
Amblyopia often causes no obvious symptoms and can be difficult to detect, especially in young children. In many cases, it is only identified during an eye test.
Common signs and symptoms include:
- Reduced vision in one eye
- Difficulty judging distances or reduced depth perception
- Eyes not working together properly
In children, amblyopia may also cause noticeable behaviours such as:
- Squinting or shutting one eye
- Tilting or turning the head to see more clearly
- Difficulty focusing or struggling with vision
Treatment for Amblyopia
Treatment for amblyopia focuses on improving vision in the weaker eye and addressing any underlying eye problems. It is most effective when started early in childhood.
Common treatment options include:
Corrective Lenses
Glasses are often the first step in treatment for amblyopia. They correct refractive errors such as hyperopia, myopia and astigmatism, helping both eyes to focus more clearly. Contact lenses may be recommended for older children under supervision.
Treating Underlying Eye Conditions
If lazy eye is caused by another eye condition, such as cataract or squint, treatment may involve correcting the underlying issue first.
Eye Patch
A patch is placed over the stronger eye to encourage the weaker eye to work harder. This is usually worn for a few hours each day over several weeks or months.
Atropine Eye Drops
Atropine drops can be used in the stronger eye to temporarily blur vision, encouraging the weaker eye to be more used. This is often an alternative to eye patches for children who find patches uncomfortable.
Frequently Asked Questions
How long does it take to treat amblyopia?
Treatment can take a few months to a few years, depending on the child’s age, the severity of the condition and how consistently treatment is followed.
What happens if amblyopia is not treated?
If left untreated, amblyopia can lead to permanent reduced vision in the affected eye. It may also affect depth perception
Can amblyopia be treated in adults?
Yes, it can sometimes be treated in adults. However, treatment is most effective during early childhood, when the visual system is still developing. Some improvement in vision may still be possible in older children and adults, depending on the severity of the condition.
Disclaimer: The advice in this article is for informational purposes only and does not replace medical care or an in-person check-up. Please check with an eye care professional before purchasing any products or remedies. For information on our article review process, please refer to our Editorial Policy.
Tina Patel is a qualified Contact Lens Optician at Feel Good Contacts with over 25 years of experience in the optical industry. She is a member of ABDO and registered with the GOC. Tina holds a BSc. (Hons) in Optical Management from Anglia Ruskin University and qualified as a Dispensing Optician in 2002. In 2007, she further specialised by completing advanced training in contact lenses, gaining her qualification as a Contact Lens Optician. She now shares her clinical expertise through teaching at City, University of London, guiding future opticians.
