Amblyopia: Lazy Eye Causes, Symptoms, And Treatment
Amblyopia (a.k.a: Lazy Eye or Ambylopia) is a condition in which a person has decreased vision either in one or both the eyes which cannot be corrected even by using glasses. This is a developmental disorder that occurs when the eyes and the brain do not work in sync to produce visual images. Initially, this results in poor vision and if left untreated, it could lead to vision loss.
Amblyopia is generally observed in children between birth and the age of seven. Untreated amblyopia has been stated to be a leading cause of vision loss in children. About 2-4% of children are reported to be suffering from Amblyopia.
What is Lazy Eye?
Lazy Eye / Amblyopia is a developmental disorder of the eye that is characterized by abnormal visual development. The weaker eye usually wanders inward or outward and this results in poor perception of images. This occurs when the brain and the eyes lack proper coordination.
Amblyopia is generally mistook for strabismus (squint eye or crossed eye). However, squint eye when left untreated may develop lazy eye due to poor coordination between both the eyes in transmitting signals.
What Causes Amblyopia?
Improper e visual processing by the brain is the chief cause of Amblyopia or lazy eye. This may also occur when the nerve fibers fail to transmit signals from the brain to the eye or vice versa.
The other causes of Amblyopia include:
- Squint eye (turning of the eye towards one side)
- Family history of Amblyopia
- Difference in the level of perception of objects
- Damage caused to an eye due to accident or trauma
- Vitamin A deficiency
- Scar or ulcer on the cornea
- Eye surgery
- Visual defects such as astigmatism, nearsightedness or farsightedness
What are the symptoms of Amblyopia?
The initial symptoms of Amblyopia are difficult to diagnose until the condition becomes severe. The signs and symptoms of amblyopia include:
- Poor visual perception
- Inward or outward movement of the eyes
- Head tilting for looking at an object
- Bumping into objects on one side
- Double vision
What are the risk factors of Amblyopia?
The factors that increase the risk of Amblyopia include:
- Family history of amblyopia
- Developmental abnormalities
- Children lying in the age group of 0-8
- Developmental abnormalities
- Premature birth
- Small size at birth
What are the Complications of Amblyopia?
The complications that arise due to untreated amblyopia include partial or permanent vision loss. It is the most common cause of vision loss reported among the adult population.
Usually in patients with amblyopia, only one eye is affected. Immediate medical intervention should be considered upon finding a difference in visual acuity between both eyes. The tests performed to assess the eye function include:
- Identifying the letters of different font sizes on the screen
- Following the direction of light focused on one eye each and later with both eyes
- Allowing the doctor to monitor your eye with the help of a magnifying lens
- Test to check your clarity of vision
- Test to check the muscle strength of one or both eyes
- Test to check the focusing ability of both the eyes
How is Amblyopia Treated?
Amblyopia can be effectively treated by use of eye drops, eyeglasses, contact lenses, eye patches and vision therapy.
Eyeglasses/Contact Lenses: Astigmatism, nearsightedness or farsightedness could be an underlying cause of lazy eye. This can be rectified with the help of eyeglasses or contact lenses.
Eye Drops: Eye drops are used to cloud the vision of the normal eye. This encourages the patient to use the weaker eye. Repeated stimulation of the weaker eye helps in improving visual processing and vision.
Eyepatch: An eye patch is worn over the normal eye. This is done to strengthen the weaker eye and promotes eye function. Depending upon the severity of the condition, the patch is recommended to be worn for at least 2-3 hours in a day. This helps in developing the affected area of the brain that controls vision.
Bangerter Filter: A Bangerter filter is a special filter placed over the lens of the stronger eye. This filter blurs the images passing through the lens, thus stimulating the function of the weaker eye.
Surgery: In case of crossed eye, surgery is performed to realign the muscles of the eye. The eye muscles are adjusted that may improve the vision in the weaker eye.
The duration of treatment for Amblyopia helps improve vision that may range from weeks to months. However, in severe conditions, the treatment usually ranges between 6 months to 2 years.
Including supportive therapies such as drawing, playing computer games or solving puzzles has proved to be effective in enhancing the function of the weaker eye.
Some frequently asked question about Amblyopia:
- How does Amblyopia affect the eyes?
The eye captures and processes the image captured by both the eyes and sends signals to the brain. In case of Amblyopia, the eye fails to process the image from the weaker eye. Thus only the signals from the stronger eye are transmitted to the brain that results in a poor vision of the weaker eye.
Further ignoring the symptoms of the weaker eye results in vision loss.
- How can I prevent the occurrence of lazy eye?
Early diagnosis and treatment prevent the occurrence of lazy eye. Rectifying the unequal refractive errors and use of corrective measures such as the use of eyeglasses and contact lenses also prevents the occurrence of lazy eye.
- How does Amblyopia affect my daily activities?
Performing activities that require good depth perception may be affected by Amblyopia. Timely treatment and performing eye exercises can improve this.
- Can Amblyopia be reversed?
Yes. Early detection and treatment of Amblyopia or the underlying cause help in reversing the condition. This can be rectified by effective use of eye patches, eye drops or eyeglasses.