In children with normal vision, the brain develops the ability to use both the right and left eye together starting as early as the first few months of life. This is called binocular vision i.e. image inputs from both eyes being fused in the brain as a single image.
In children with amblyopia or lazy eye the brain prefers to use the eye with good vision and starts ignoring or blocking inputs from the eye which has inferior quality of images. Because this happens very early in life, the brain does not learn to use the two eyes together and the lazy eye doesn’t get a chance to develop as it is ignored by the brain.
Patching therapy is a form of amblyopia therapy used to strengthen the weak or lazy eye.
Here are some of the common queries which parents have about eye patching and how it must be done.
How does patching therapy work?
In patching therapy, an occluder or patch is placed over the “good” eye to block its visual input, and in turn to force the brain to use the weak/amblyopic eye. With the normal eye covered, games or activities that demand vision or hand eye co-ordination are carried out by the lazy eye which slowly enhances it’s vision and development in the brain.
How should I patch my child’s eye?
The good eye may be patched with various techniques like ready eye patches which have self adhesive layer or using a tissue paper, folded and stuck over the eye with meditape or using a soft cloth occluder worn over the eye like a pirate eye patch etc. The method used may be different but it is important that the good eye is blocked completely and the child mustn’t be able to see from the sides or peep above the patch either.
How long do I generally need to patch my child’s eye?
Duration of patching and time to be spent daily with patching is generally determined by your eye doctor based on the child’d age, cause of amblyopia and how severe is the amblyopia. Therapy may be required for a few months to few years as well.
If my child has glasses does he/she need to wear glasses with patching?
Yes, patching therapy always works best when the appropriate spectacle correction is there in front the lazy eye. So glasses are to be given and the patch is preferably placed directly over the eye under the glass rather than covering the glass to prevent peeping from the sides.
What should my child do after wearing the patch?
Wearing an eye patch is not always enjoyable and it takes some time for the brain to adjust to having the dominant eye covered. Spending some fun time with your child or being close to your child during this time can make the transition easier.
Start with simple activities and then move to more challenging ones to help build your child’s confidence. Reading, coloring, painting, crafts such as cutting and pasting, solving puzzles, playing catch are all fun activities that require good hand/eye coordination and will exercise the lazy eye well. Even if your child is too young to read, sit together looking at the pictures in children’s books to make the weak eye work during patching.
Do I need to complete patching at a single stretch in a day?
Based on your and your child’s comfort patching may be done at once, or can be split in two sessions (for eg: if patching is prescribed for 2 hours daily, you can patch for an hour in the morning and an hour in the evening).
It’s a struggle to get patching done, so can I wait for my child to grow older and then start patching?
Unfortunately the answer is no. Our vision develops fatest in the early years of life and our brain has a sensitive period of upto 8-10 years of age during which it responds well to patching. Beyond this age and in still older children the response to patching may be slow to very minimal and there is a risk for the eye to have poor vision due to amblyopia through adulthood.
Are there any alternatives like medicines or surgery to improve vision instead of patching?
Other forms of therapy like penalisation of the better eye with eyedrops, systemic medication for amblyopia etc have been studied and tried. Certain eyedrops may be given in addition to patching or instead of patching in selected cases as decided by your treating doctor, but over all patching therapy has shown superior results. Surgery in the form of squint correction, removal of cataract etc may improve vision to some extent but these too need long term patching for vision improvement.
Are there any side effects of patching? Can it affect the eye being patched?
Sometimes while using adhesive patches or sticking tape children may develop localised reaction (redness/ itching/rashes) over the skin around the eye due to the adhesive material. This does not affect the eye from inside and can be treated by applying cooling lotion locally or changing the type of patch material used. A more serious side effect that one must be very cautious about is the amblyopic eye getting better than the initial “good eye” which we were patching and the good eye now becoming lazy or amblyopia. This is called as reverse amblyopia. In children with amblyopia due to squint in one eye we may see this change that squint now starts being manifested in the other eye too or alternates in both the eyes. While this is a good sign that both the eyes are now equally good, it is very important to follow up regularly when patching therapy is given to prevent the good eye from becoming amblyopic.
DNB FICO(UK) F.LVPEI
Senior Consutlant, Pediatric Ophthalmology, Strabismus & Neurophthalmolgy