eye patch for lazy eye

Eye patching for kids

Eye patching is a treatment for amblyopia or lazy eye. Amblyopia when one eye does not develop normal eyesight. Patching of the dominant (good) eye helps the weak eye get stronger. The treatment works very well when patching instructions are carefully followed. The best time to use eye patching to correct amblyopia is during early childhood.

What is a lazy eye?

“Lazy eye” also sometimes called amblyopia, is the medical term used when the vision in one eye (common) or both eyes (less common) is reduced because the eye fails to work properly with the brain 1). Amblyopia is when vision in one or both eyes does not develop properly during childhood. The eye itself looks normal, but for various reasons the brain favors the other eye. Amblyopia is a neurodevelopmental disorder that arises from abnormal processing of visual images that leads to a functional reduction of visual acuity and its associated risk factors 2). An estimated 2%–3% of the population suffer from amblyopia 3). Amblyopia is a common problem in babies and young children. Unless it is successfully treated in early childhood amblyopia usually persists into adulthood, and is the most common cause of permanent one-eye vision impairment among children and young and middle-aged adults.

Lazy eye can result from any condition that prevents the eye from focusing clearly. Sometimes this causes the weaker (“lazy”) eye to wander outward, inward, upward or downward. When an eye wanders causing misalignment of the two eyes, that condition is called strabismus. With strabismus, the eyes can cross in (esotropia) or turn out (exotropia). Amblyopia and strabismus are commonly confused. When most people think of “lazy eye” they are actually thinking of wandering or misaligned eyes, which is strabismus. “Lazy eye” is amblyopia — poor vision in one or both eyes. This poor vision (amblyopia) can lead to eye misalignment (strabismus). Strabismus is more commonly referred to as crossed eyes, wandering eyes, or drifting eyes. If for some reason one eye of a child has decreased vision, the brain will not use that eye and it becomes lazy (reduced vision) from lack of use. That is amblyopia — the eye is lazy from lack of use. If one eye happens to be looking somewhere other than the other eye, that is strabismus. Lazy eyes with amblyopia just do not see well, it DOES NOT mean they wander or drift 4).

Occasionally, amblyopia is caused by a clouding of the front part of the eye, a condition called cataract.

Early vision screening by a pediatrician, family doctor or an ophthalmologist is important in detecting children with amblyopia as young as possible. A number of eye diseases can contribute to the development of amblyopia.

In 2016, the American Academy of Pediatrics, American Association for Pediatric Ophthalmology and Strabismus, American Academy of Certified Orthoptists, and American Academy of Ophthalmology released a joint clinical report recommending preschool vision screening 5). The joint report recommends vision assessment in children aged 6 months to 3 years with physical examination (eg, external inspection, the fixation and follow test, the red reflex test, and pupil examination). Instrument-based vision screening (with autorefractors or photoscreeners) may be used, when available, in children aged 1 to 3 years. Visual acuity screening may be attempted at age 3 years using HOTV or Lea Symbols charts; children aged 4 to 5 years should have visual acuity assessed using HOTV or Lea Symbols charts, the cover-uncover test, and the red reflex test 6), 7).

The American Academy of Family Physicians recommends vision screening in all children at least once between the ages of 3 and 5 years to detect amblyopia or its risk factors; it concluded that the current evidence is insufficient to assess the balance of benefits and harms of vision screening in children younger than 3 years 8).

The American Optometric Association recommends initial vision screening in infants at birth. Regular comprehensive eye examinations should occur at age 6 months, age 3 years, and prior to entry into first grade; eye examinations should then occur at 2-year intervals unless children are considered at high risk for vision abnormalities 9).

The US Preventive Services Task Force 10) makes recommendations about the effectiveness of specific preventive care services for patients without obvious related signs or symptoms. It bases its recommendations on the evidence of both the benefits and harms of the service and an assessment of the balance. The US Preventive Services Task Force recommended vision screening for amblyopia and its risk factors in children aged 3 to 5 years (B recommendation). The USPSTF concluded that the evidence was insufficient to assess the balance of benefits and harms of vision screening in children younger than 3 years (I statement) 11).

Amblyopia treatment should be started as early as possible because 12):

  • over time the amblyopic “lazy” eye could become permanently blind;
  • depth perception (3-D vision) could be lost; and
  • if the other, better-seeing, eye becomes diseased or injured, the amblyopic “lazy” eye cannot replace the loss in vision.

Treatment of amblyopia

If the child has a significant refractive error, be it long sightedness, short sightedness or astigmatism, glasses will be prescribed. The initial treatment for children with amblyopia and a refractive error, should be full time spectacle wear for 3-4 months. If, at the end of this period, the vision in the amblyopic eye has not started to improve, occlusion therapy in the form of eye patching is recommended. If there has been some visual improvement with glasses alone, occlusion therapy is not needed, but will be started when there is no further visual improvement with glasses alone.

How does eye patching work?

By putting a patch over the better seeing eye the child’s brain is forced to “recognize” the image from the amblyopic eye. This stimulates the development of nerve pathways between the amblyopic eye and the brain, so improving the vision in this eye.

How to put on the eye patch?

Remember that if your child’s vision is poor in their amblyopic eye they may be clumsy when wearing their eye patch. The eye patch will also prevent any 3D vision that your child may have. Therefore they will not be able to judge distances as well when wearing their eye patch.

  • Eye patch is applied directly to the skin. These eye patches are designed to be worn on the face underneath any glasses required. They are also available as hypoallergic patches for those with very sensitive skin. These are the most suitable eye patches for children with very poor vision in their amblyopic eye because it is harder for them to move the eye patch to try to peep around it.
  • Eye patch attached to the glasses. These eye patches are designed to be worn on the child’s glasses but it will be necessary to closely monitor your child to ensure that they do not try to peep by moving the patch sideways or pulling their glasses down to look over the top of the patch. Some children respond well to this frosted tape applied to their glasses but again there may be a temptation to peep.

Patching a baby or toddler

Putting some thick mittens on your child will mean that they are less able to easily remove the eye patch and / or glasses. The mittens can be tucked or sewn into the sleeves of a garment. Taking your child out for a walk in the pushchair with mittens and a eye patch will help to distract them and is an activity that most children enjoy. Sometimes eye patching at mealtimes when the child is occupied with their food can work. Be prepared that you may initially have to sit and play with your child constantly to ensure that the patch is not removed and in the early stages of patching they may be quite upset. As the vision improves in the amblyopic eye their acceptance of the eye patch should hopefully also improve.

What kind of eye patch should my child use?

The best kind of eye patch is an orthoptic patch with adhesive on the back. This type of patch is similar to a Band-Aid®. They come in different sizes and colors. You should put the patch directly on your child’s skin around his/her eye. Some kids are sensitive to the adhesive. If your child has this problem, you can try using a different brand of patches. You can also try putting a lubricant (like lotion) or Milk of Magnesia on their skin. Milk of Magnesia is a liquid that reduces the skin’s contact with adhesive. Cover the skin around your child’s eye with it. Wait for it to dry into a powder and then put on the eye patch. Another type of patches is made of cloth. If your child wears glasses, you can put a cloth patch over his/her glasses. For the patch to work well the glasses should fit tightly and the cloth should not have any holes. “Pirate patches” usually do not fit close enough to be effective.

How often does my child need to use an eye patch?

Your child should wear an eye patch for either full or part-time during the day. Talk to your child’s eye doctor about how many hours he/she recommends.

How many hours a day will the eye patch have to be worn for?

There is good evidence that 2 hours of patching a day is as effective as 6 hours of patching for moderate cases of amblyopia (vision between 20/40 – 20/80 or 6/12-6/24). In more severe amblyopia patching for 6 hours per day is usually recommended. It has been shown that full time patching is no more effective than patching for 6 hours per day, even in severe amblyopia.

Studies that have electronically monitored the actual number of hours a patch is worn for, as apposed to the number of hours prescribed, have shown that that 80% of the improvement in vision occurs within the first 6 weeks of treatment.

Several large studies have looked at the total number of hours of patching needed to achieve the best improvement in vision and the answer varied between 150-400 hours!

In the ideal situation, patching is gradually reduced and then stopped when the vision is equal in both eyes. However a more common scenario is that the vision in the amblyopic eye plateaus at 6/12 or 20/40 level and patching is tapered off at this point. Approximately 70% of children achieve this level of vision with patching treatment.

Is it worth me patching at all? A two-hour dose of patching has been recommended, but my child will only wear the patch for half an hour.

Yes, any patching is better than none at all and you may be able to gradually increase the length of time the patch is worn as your child’s vision improves.

Do I have to do the eye patching in one session each day? What do I do if I forget one day?

The patching can be worn continuously for the prescribed time or it can be split up eg. 2 hours continuously or two 1 hour slots – whichever fits best into your routine. However, many parents find that splitting it up causes more “fuss” from the child! If you forget to patch one day try to patch for twice the recommended time the next day.

When should my child wear an eye patch?

It does not matter when your child wears an eye patch. As long as your child is awake and has his/her eyes open, wearing an eye patch can strengthen your child’s weak eye. There are often questions about whether children should patch at school or at home. At home, children are under the care of parents or other family who may be more vigilant about monitoring patching than is possible at school. On the other hand, patching during school may give your child and classmates an opportunity to learn about accepting differences between children. Every child is unique and parents should be flexible in choosing when to schedule patching.

The vision may improve more quickly if the child is “working” the amblyopic eye by performing some sort of close work and most children will enjoy choosing from a variety of activities such as reading (or being read to), coloring, making jigsaws or playing with electronic games.

How do I persuade my child to wear a patch?

This is a challenge for many parents, especially if the vision in their child’s amblyopic eye is very poor and the child is objecting strongly. Unfortunately this is an area of treatment where there is no “quick fix” but it is also a brilliant opportunity to spend a great deal of time and enjoy playing with your child.

It is necessary to adopt a firm approach and probably easiest for everyone if the patch can become part of the child’s daily routine.

Patience and perseverance will be required and some children require a very structured approach to the patching routine eg. Setting the patch dose time on a cooking timer. Many children prefer to remove their own patch when the time is up.

Parents might like to start with a short explanation eg. Putting the clever eye to sleep so the lazy-bones eye can do some work.

It is probably best not to patch your child when they are tired as they are less likely to cooperate.

Often a routine of child gets up, washes face, glasses if required put on, followed by patch on and the teacher or nursery staff remove the patch at mid morning break or lunchtime works well for 2 or 4 hour doses of patching. Sometimes children will tolerate the patch better for someone other than their parents!

Many children respond well to daily star charts and charts such as these where they draw a smiley mouth if they have worn their patch and a sad mouth if they have not.

Parents may wish to consider a small reward at the end of each week if the patch has been worn well each day. Children may like to bring a picture that they have drawn or colored in whist wearing their patch to their eye clinic appointments to “show and tell.”

When is it too late to start eye patching treatment?

Although the connections between a child’s eyes and their brain are normally fully formed by the age of 8-9 years, eye patching therapy can still be successful up to the age of 14 in some cases.

What if my child does not want to wear an eye patch?

It is very common for children to refuse to wear an eye patch. It may take a lot of encouragement from family, friends, and teachers for your child not to remove the patch. You can consider rewarding your child if he/she keeps the patch on for the necessary amount of time. You can also let your child choose the color and pattern of his/her eye patch. You can also try patching during your child’s favorite activities. Some kids are more willing to wear patches while they are watching TV or playing games.

How long does it take for eye patching to work?

The duration of patching will depend on the severity of the amblyopia, the age of the child and how well the child and their parents are able to stick to the prescribed patching regime!

Your child’s vision may improve a few weeks after starting patching. It may take many months for the best results. Your child’s eye doctor will monitor your child’s vision closely during and after eye patching. Your child’s eye doctor may recommend that he/she occasionally uses eye patching even after his/her vision has improved. This will help make sure your child’s eyesight does not get worse.

I have noticed the turn sometimes swaps over into the good eye. What should I do?

If the turn swaps into the good eye occasionally this is a good sign for the vision, it means that the vision is becoming more equal in the two eyes. If the turn just swaps over occasionally keep patching for the recommended time. If at any point you think that the good eye is turning more than the “bad” one then you should stop the patch and contact your eye clinic for advice.

Will the improvement in vision be permanent?

In approximately 80% of children the visual improvement is maintained for at least a year after patching is stopped. Recurrence of the amblyopia is more likely to occur if patching is stopped suddenly, if the amblyopic eye is much more long sighted than the good eye (anisometropic amblyopia) or when the amblyopia is a combination of strabismic and anisometropic amblyopia. This is why it is important to continue monitoring the vision until the child is 8-9 years of age, so any recurrence of the amblyopia can be treated.

Interestingly there is evidence that should a person loose vision in their good eye in later life, the vision in the amblyopic eye can improve spontaneously to the best level that was achieved with patching.

How does atropine penalisation work and when is it used instead of patching?

As an alternative to eye patching the stronger eye can be “penalized” by using atropine drops once a day to this eye. These drops weaken the focusing mechanism of the eye so reducing the close up vision to such an extent that the child’s brain “chooses” the image form the amblyopic eye rather than the blurred image from the stronger eye.

Penalisation of the better seeing eye with atropine drops or ointment has been demonstrated to be as effective as eye patching for moderate amblyopia (20/40 to 20/100; 6/12 to 6/30). It has also been used to successfully treat severe amblyopia.

Although the initial improvement in vision appears to be more rapid with eye patching, the visual improvement after six months of treatment is equally good.

Why isn’t atropine penalisation the first choice of treatment for amblyopia?

While atropine is as effective as eye patching for treating amblyopia and may be a more acceptable form of treatment to some children and their parents, it is less controllable than eye patching, as the effects of the atropine last for up to 2 weeks and can, rarely, cause a drop in vision in the good eye. This is known as reversal amblyopia and is the reason why a child having atropine penalisation needs to be seen every 2-3 weeks, so the vision in both eyes can be closely monitored. The risk of reversal amblyopia and the increased number of clinic visits are the main reasons why atropine penalisation is not routinely used as the initial treatment for amblyopia by most ophthalmologists.

Atropine penalisation tends to be used if eye patching treatment has been unsuccessful despite good compliance with patching, or of the child is unable to tolerate wearing a patch.

What happens if the vision does not improve with glasses, eye patching and /or atropine drops?

Occasionally the vision in the amblyopic eye does not improve despite the fact that the glasses have been worn full time and eye patching and / or atropine drops has been carried out as instructed. When this happens the ophthalmologist will re-examine the back of the eye again to make sure that there is not a subtle abnormality of the optic nerve or retina, which might not have been apparent at the time of the initial examination, that could be the cause of the poor vision.

If it appears that the chance of visual improvement with further treatment is slim and if the child is likely to find continued treatment upsetting, a decision may be taken to stop amblyopia treatment.

Why can’t my child have an operation to improve the sight in their lazy eye instead of the eye patch?

A strabismus operation can only restore the use of the two eyes together and / or improve the appearance of the strabismus eye. It does not treat the poor vision in the amblyopic eye, this can only be done by patching / atropine drops and / or glasses.

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