Amblyopia

Amblyopia, often known as lazy eye, refers to an early childhood disorder in which a child's vision in one eye does not develop properly. When a patient develops amblyopia, the brain concentrates one eye over the other, ignoring the "lazy" eye. The nerve cells that are responsible for eye vision fail to mature normally if that particular eye is not stimulated appropriately. 

Amblyopia mostly affects people from infancy to the age of seven. It is the most common cause of eyesight loss in children. However, amblyopia rarely affects the two eyes. 

Early detection and treatment can help your child avoid long-term visual problems. Glasses, contact lenses, or patching therapy may typically correct the vision of the eye with poor sight.

Signs and Symptoms of Amblyopia 

A minor who has amblyopia will be unable to concentrate on one of the eyes properly. The opposite eye will compensate for the impairment to the point that the affected eye tends to suffer. Also, the affected eye won’t get clearer images. When the brain does not receive clear input, it begins to dismiss it with time. 

In most situations, the brain and the more robust eye compensate so well for the deficiency that the child is unaware of the problem. As a result, the lazy eye can go undetected until the minor undergoes a normal eye examination. 

The following are some of the signs and symptoms of a lazy eye:

• Double vision 
• Blurry vision 
• Eyes that appear not to function together 
• Inward or outward wandering of the eye 
• Shutting or squinting of the eye 
• Poor depth perception 
• Tilting of the head 

Causes of Amblyopia 

Early during childhood, an abnormal visual experience affects the neuronal connections between a tiny layer of tissue (retina) located at the back of the eye and the brain. This results in a lazy eye. The weak, impaired sight gets less visual information than the stronger one. The brain tends to suppress or ignore data from the weak eye as the ability of the eye to function together deteriorates. 

Amblyopia in adults and children can be caused by anything obstructing vision in one of the eyes throughout a child's growth. Whereas the causes for this are unknown, the brain suppresses images from the afflicted eye. 

Some possible causes of amblyopia for adults and children include; 

• Strabismus

With strabismus, the muscles that keep the eyes in position are out of balance. This makes the eyes cross or even turn out. Because of the muscle imbalance, it's difficult for the two eyes to track things at the same time. Strabismus is also an inheritable condition, or it can occur due to nearsightedness, eye injury, or a viral infection. 

• Anisometropic amblyopia

When light does not focus properly while traveling via the lens of the eye, it is called a amblyopia refractive error. It develops as a result of farsightedness, nearsightedness, and astigmatism condition whereby the cornea surface or lens is uneven, resulting in blurry vision. When a child has anisometropic amblyopia, one eye is more nearsighted or farsighted, unlike the other. This causes amblyopia to develop in the affected eye.

• Stimulus deprivation amblyopia

This is the rarest type of amblyopia. One eye becomes weaker as it is unable to see. Both can be affected at times. This could result from eye injury, congenital cataract, glaucoma, corneal ulcer, ptosis (drooping eyelid), or eye surgery. 

Risk Factors of Amblyopia 

The following factors have been linked to an increased incidence of the lazy eye:

• Early or premature birth
• The baby being small in size 
• A family history of amblyopia
• Disabilities associated development

Amblyopia Diagnosis 

It is critical to have an amblyopia diagnosis as early as possible, especially before the age of six. However, this is not always achievable since the minor might not be aware that there is a problem.

Regular examination of the eye:

It’s generally essential for children to undergo their first eye test at the age of three and five or before they begin school. With this, the majority of amblyopia cases can be diagnosed and treated sooner. 

In case the physician (ophthalmologist or optometrist) suspects that your child has amblyopia, they will do additional testing before making a diagnosis.

The physician will examine every eye separately to identify if nearsightedness or far-sightedness exists, as well as the severity of the condition. The minor will also be thoroughly reviewed to see if there is an eye turn. 

Amblyopia Treatment 

It is critical to begin treatment for amblyopia as early as possible during childhood. This is when the eye's and brain's intricate connections are still developing. While nearly half of minors aging between 7 and 17 react well to treatment, the greatest outcome is evident if treatment begins before the age of seven. 

Normally, the treatment options are determined by the source of the child's amblyopia and the extent to which the issue impacts his or her vision. In such cases, the doctor might suggest the following;

• Glasses 

The physician can recommend contact lenses or glasses to the child who has far-sightedness, near-sightedness, or astigmatism. Usually, the child will be required to put them on every time to allow the specialist to assess how efficient they are in treating the visual amblyopia problems. An eye turn can also be corrected with glasses. Amblyopia can sometimes be corrected with spectacles alone, requiring no further therapy. 

Children rarely report that their vision improves when they don't have their glasses on. Therefore, for the treatment to be more effective, they have to wear them all the time. 

• Patches for the eyes

The child has to put an eye patch above the good vision eye for about 2 to 6 hours or even more each day to stimulate the impaired sight. Using an eye patch for an extended period might lead to amblyopia in the patched eye in rare situations. It is, however, frequently reversible.

• Eyedrops

A drop of atropine (Isopto Atropine) medication can temporarily obscure vision in the good eye. The drops are normally recommended for use during the weekends or daily. It encourages the minor to utilize the less strong eye and provides an option to a patch. Irritation of the eye and light sensitivity is, however, the two common side effects. 

• Bangerter filter 

This unique filter is applied to the strong eye's glass lens. Like the eye patch, the filter tends to blur the good eye while stimulating the weak one. 

• Surgical procedure

If your child has cataracts or drooping eyelids that induce deprivation amblyopia, amblyopia surgery may be necessary. In addition to various amblyopia therapies, the doctor may suggest a surgical correction to help straighten the eyes if they keep on crossing or wandering apart even with the suitable glasses.

• Exercises 

Orthoptics are exercises that assist repair vision. However, there are no specific activities that can help with amblyopia. Based on the child's age, the strong eye might get patched while the weak eye is stimulated with a variety of vision-intensive activities. This can include dot-to-dot drawing, coloring, word games, and Lego construction. 

As soon as the strength in the weaker eye has recovered, other activities like home-based pencil push-ups (HBPP) might be considered. It includes gradually sliding a pencil to the tip of the nose while concentrating on the pencil end till it gets blurry.

On the other hand, home-based activities are unlikely to be employed as a first-line treatment for persons with amblyopia. Most orthoptic exercises involve seeing using the two eyes. They are designed for individuals who have various vision issues. 

There are activity-based treatments available, including sketching, performing puzzles, or playing some computer games. The efficacy of combining these exercises with other therapies has yet to be proven. However, research on new treatments is still in progress.

Most children who have amblyopia improve their vision after several weeks or months with proper therapy. The duration of treatment can range from six months up to two years.

It's critical to keep an eye on your child for recurrence of amblyopia, which can affect up to 25% of minors with the condition. If the disease reappears, you or the child will need to restart the treatment.

Complications of Amblyopia 

Some of the possible complications associated with amblyopia include; 

Blindness: If left untreated, the patient's vision in the affected eye may progressively deteriorate and eventually be lost. Such loss of vision is normally irreversible. According to research, amblyopia is the leading cause of vision impairment of one eye among young and middle-aged people. 

Eye turn: Strabismus, or misalignment of the eyes, may sometimes become permanent.

Central eye vision: A person's central vision might not develop appropriately if lazy eye is not addressed during childhood. Their ability to perform particular duties may be severely affected as a result of the condition. 

Conclusion 

In children, amblyopia is a prevalent cause of vision loss. Early and routine eyesight screenings for children are recommended so that physicians can notice any vision abnormalities. Implementing treatment options, like a patch or glasses, before vision loss becomes severe can be quite beneficial. 

Many physicians and schools provide vision screening. Also, if you observe vision or any eye concerns in your child, contact your healthcare provider immediately.