What is amblyopia?
Amblyopia is a form of weak vision.
The eyesight is impaired and there are defects in formal vision.
It is a visual impairment that is often diagnosed in childhood.
In this article, you can find out more about amblyopia, its causes and treatment.
Development of amblyopia
Amblyopia is caused by the brain’s inability to process visual sensory impressions.
Perceptions are transmitted to the human brain via nerves to ensure sharp vision – this is how vision develops.
If the transmission of perceptions is disturbed, this results in incorrect processing of visual impressions.
Those affected then experience a visual impairment – amblyopia.
Causes of amblyopia
There are various causes that lead to a disturbance in the transmission of sensory impressions to the brain.
These include, for example
- Squinting eye (strabismus)
- defective vision(short-sightedness, long-sightedness, astigmatism)
- Cloudy eye lens
- Misalignment of the eyelid, e.g. drooping of the upper eyelid
Most patients suffer from a one-sided visual impairment.
To compensate for the impairment, the perception of the affected eye is suppressed by the brain.
This impairs the development of vision.
There are also some cases in which both eyes are affected.
Who is affected by amblyopia?
Amblyopia is a common visual impairment in children.
Two to five percent of all children are affected by amblyopia.
Amblyopia often develops before the age of two, but is possible up to the age of eight – this is when vision development is complete.
Symptoms of amblyopia
Children rarely complain about the symptoms themselves.
In early childhood, the perception of symptoms cannot even be communicated.
It is therefore all the more important that parents – regardless of the exact age – take a closer look at visual behavior:
- Is your child cross-eyed?
- Does your child have to hold objects closer to their face to recognize them?
- Does your school-age child have problems with reading/writing?
These are indications that your child may be suffering from vision problems.
In this case, you should consult an eye specialist.
You should also attend check-ups even if there are no signs of visual impairment – early detection is particularly important for amblyopia.
More on this later.
Treatment of amblyopia
The treatment of amblyopia is generally possible if it is recognized in time.
The treatment method depends on the underlying cause.
An attempt is made to treat the underlying disease specifically in order to eliminate the disruptive factor for the transmission of sensory perception to the brain.
Depending on the disease, this may look like this:
- Visual aids for defective vision
- Cataract surgery for lens opacities
- Eye muscle surgery for strabismus
In the case of defective vision, the visual aid should first improve visual acuity.
Cataract surgery is also performed first if the lens is cloudy.
This is followed by treatment for amblyopia.
In the case of strabismus, the order is often reversed: amblyopia treatment first, followed by strabismus treatment.
Occlusion therapy – treatment of amblyopia
The best-known and most promising treatment method for amblyopia is to cover the affected eye – also known as patching or occlusion therapy.
This involves covering the healthy eye with a special patch.
It is also possible to wear an eye patch or glasses with a cover.
The latter method requires glasses to be worn consistently.
Covering the healthy eye stimulates development in the eye with lower visual acuity.
The therapy usually lasts until both eyes have the same visual acuity.
Atropine drops for amblyopia
In addition to masking treatment, atropine drops can also be administered.
These are pupil-dilating eye drops that are applied to the healthy eye.
This also stimulates the development of poor vision.
The application of the drops is often easier than occlusion therapy and is better accepted by children.
A combination of occlusion therapy and therapy with atropine drops is also possible.
At what age can amblyopia be treated?
The earlier amblyopia is discovered, the better the chances of recovery.
In the worst-case scenario, amblyopia can lead to a loss of vision.
While the visual center is still developing (up to the age of eight to ten), treatment is more likely to be successful.
After that, the chances of success decrease.
Early detection
Attending annual check-ups helps with early detection and diagnosis.
From birth, the eyes should be checked during the check-ups.
The red reflex is tested (so-called Brückner test).
The following tests are also important in the diagnosis of visual disorders and therefore the cause of amblyopia:
- Long stereo test: testing of spatial vision – strabismus is tested.
- Hirschberg test: Position and symmetry of the cornea are checked – detection of strabismus.
- Visual acuity test: visual acuity test, from the age of three.
- Autorefraction: Automated examination – determination of visual acuity, detection of strabismus and cataracts.
Diagnosis of amblyopia
If any abnormalities are found during early detection, your doctor will refer you to a specialist.
Ophthalmologists and orthoptists are usually consulted for further clarification.
Further examinations will be carried out to establish a diagnosis:
- Cover test: Shield diagnostics.
- Mobility tests: assessment of eye movement disorders.
- Fusion test: Coordination between brain and eyes.
- Objective refraction in cycloplegia – use of the autorefractometer after short-term paralysis of the ciliary muscle with the aid of medication.
- Slit-lamp biomicroscopy: the anterior segment of the eye is examined.
- Funduscopy: examination of the fundus, retina and blood vessels.
Frequently asked questions & answers about amblyopia
Where does amblyopia come from?
The processing of visual impressions ensures that vision develops further in childhood.
Amblyopia occurs when at least one eye suffers from a visual impairment.
This disrupts the transmission of a visual impression to the brain, resulting in blurred visual impressions.
The brain tries to suppress the low visual acuity.
This results in impaired visual development.
Is amblyopia congenital?
Amblyopia can be congenital.
It is caused by various visual disorders.
If there is a family history of eye diseases (e.g. cataracts, strabismus, short-sightedness and long-sightedness), this represents a risk factor, as the diseases can be genetically predisposed and can lead to amblyopia.
Can amblyopia in adults be cured?
As amblyopia is a developmental deficit and children are still developing, the condition can usually be fully or partially treated in childhood.
In adults, development is largely complete.
Nevertheless, the nerve tracts continue to regenerate as the child gets older.
An improvement in vision is therefore possible to a certain extent with treatment.
