OCT 27, 2015
Amblyopia, Pediatric Ophth/Strabismus, Strabismus
Some of the common questions parents ask about the rationale for patching, the duration of patching and top tips to help your child wear their patch correctly.
- Why can’t I leave the patching until my child is older and I can reason with him/her?
Unfortunately by this time it is often “too late” for the patching to work. Vision is developing at its fastest rate in the early years of life.
- I don’t want to do this to my child. It feels cruel.
It is also cruel to deprive them of the possibility of better vision in their weak eye. An untreated strabismusing eye can lead to a virtually “blind” eye. This has consequences if the child should lose the sight of their good eye later in life through accident or eye disease.
- 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 strabismusing eye. It does not treat the poor vision in the amblyopic eye, this can only be done by patching / atropine drops and / or glasses.
- 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 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.
- Help! 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.
- How many hours a day will the 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.
- How long will patching be needed for?
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!
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.
- 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.
- When is it too late to start patching treatment?
Although the connections between a child’s eyes and their brain are normally fully formed by the age of 8-9 years, occlusion therapy can still be successful up to the age of 14 in some cases.
- What happens if the vision does not improve with glasses, patching and /or atropine penalisation?
Occasionally the vision in the amblyopic eye does not improve despite the fact that the glasses have been worn full time and patching and / or penalisation 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.
Republished, with permission, from www.squintclinic.com.