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Eye Patch One of the main treatments for amblyopia is patching the good eye and forcing the child to use to amblyopic eye. Use of the amblyopic eye improves vision in that eye, hopefully, to normal levels. Depending on the age of the child, depth of amblyopia (i.e., amount of vision loss) and others factors, patching the good eye may last from a few hours to 6-8 hours or more per day and for several weeks to several years! As a consequence, the patch becomes an important means by which to recover vision in an amblyopic child. Strictly speaking, "occlusion" is the proper term for referring to this type of amblyopia treatment and occlusion can take-on several forms, including patching. For example, over the years numerous occlusion treatment strategies have been attempted including fogging (e.g., frosting) one lens of the glasses as well as placing a neutral density filter over the good eye - a type of dark sunglass over the better eye. This article will deal only with occlusion based on the eye patch. There are two main types of patches; adhesive, those that stick to the skin, and cloth, those that either are placed on glasses or worn like a pirate patch. There are advantages and disadvantages with each type of eye patch. Adhesive Eye Patch Adhesive eye patches include those manufactured by Nexcare (3M®), Coverlet ® and Ortopad (Master Aid ®), one of which is illustrated in Figure 1. Adhesive eye patches have a peel-away side with adhesive that sticks to the skin. Ortopad adhesive patches are hypoallergenic, meaning that the chance of skin irritation is reduced, but some sensitive children can still react to the adhesive. Some of the adhesive patches (e.g., Nexcare) come in more than one size; junior and regular. The right size is dependent on the child's head size and age, but as a rule junior size is ideal for children 2 years or younger. The larger eye patches can be trimmed to better fit the child; however, don't trim too much or you'll reduce the adhesive area and reduce the ability of the patch to adhere to the child's face.
Figure 1. Child with an adhesive eye patch over the right eye. Notice that the small edge of the patch is nearest the nose.
Adhesive patches may or may not stick well to the skin , depending on the presence of oil, amount of perspiration and other factors. The main advantage of adhesive patches is that they afford complete coverage of the eye and minimize the chance that the child will look around the patch or use other behaviors to minimize the effects of the patch on recovery of vision. The disadvantages of adhesive patches include cost (about $6.00/box of 20) and allergic skin reactions. The skin adhesive patch manufacturers usually provide a warning on the box to discontinue use and to consult a physician if skin irritation occurs. In general, if skin irritation occurs, patching with an adhesive patch should be discontinued until there is complete recovery of the affected skin. In this situation, other types of occlusion or other types of therapy (e.g., dilating the good eye) may be attempted to treat the amblyopia. In use of the adhesive eye patch, skin irritation may be minimized by first applying milk of magnesia to the skin around the eye by the use of a cotton ball, says Dr. David Rogers at Nationwide Children's Hospital Eye Clinic in Columbus Ohio. Dr. Rogers reports that the milk of magnesia should dry for several minutes before the adhesive patch is applied to the skin. The milk of magnesia acts like a protective barrier between the adhesive patch and skin. At the same time, Dr. Rogers reports, the milk of magnesia does not seem to reduce the ability of the patch to stick to the skin. Even with adhesive eye patches, a determined child can still find ways to circumvent the eye patch and use the good eye for seeing, thus defeating patching therapy. In addition to simply removing the patch, children will sometimes rub the corner of the patch near the nose to allow just enough opening to see with the good eye. The opening may be so small that most parents and even some eye doctors may miss detection of the opening. So, if you see your child rub the corner of the patch near the nose please be aware of the possibility that the child may be circumventing the patch and his or her amblyopic eye will not improve. One clue that the child's good eye is not completely covered is if the child turns his or her head in the direction of the patched eye, thus allowing him or her to see out of the inner corner of the occluded eye. The head turn is the give away that the child is peaking around the patch with the good eye. Regarding application of the adhesive eye patch, the smaller corner of the eye patch should be positioned closest to the nose (see Figure 1). When applying the patch to the skin, make sure that the child's face is relaxed; that is, the child is not squinting or closing the eye(s) tightly such that wrinkles form. The child's face should be emotionless and relaxed before the eye patch is applied. Use fingers to apply pressure to all outer edges of the eye patch to ensure that all of the patch is sticking to the skin. When removing the patch, gently expose the corner of the patch near the nose and peel back the patch toward the side of the face while using the other hand to hold back the skin near where the patch is adhering to the skin. Do not allow the child to remove the patch. Having the child remove the patch is generally a bad idea. Having only the parent remove the patch lets the child know that he or she should not remove the patch on their own at any time. Of course, this is easier said than done particularly with younger children. Cloth Patch Figure 2 (below) shows three children, two of whom are wearing a cloth patch over their glasses. As with adhesive patches, there are advantages and disadvantages to cloth patches.
Figure 2. Picture of two children with cloth patches over their glasses and one child with an adhesive eye patch. Most cloth patches are secured to the child's glasses, so if the child doesn't wear glasses than cloth patches are not typically an option. Cloth patches for glasses also typically have top, bottom and side shields to prevent the child from looking around the cloth patch. Looking around the cloth patch is a big disadvantage of these types of patches and some eye doctors may not approve of the use of a cloth patch for the treatment of amblyopia. If the child looks around the cloth patch with the good eye it will defeat the purpose of occlusion and the amblyopia will not improve. Unlike adhesive patches, cloth patches do not cause skin irritation. In addition, cloth patches may be washed and reused, thus saving money. Cloth patches also often have pictures or illustrations (Figure 2) making the patch more acceptable to the child. One or two cloth patches cost about the same as a box of adhesive patches, so if the child can wear a cloth patch it might save a great deal of money, especially when the child is patched for a long period of time. At the same time, cloth patches are more difficult to locate than are adhesive patches which typically can be purchased at drug stores and discount stores. Cloth patches are often special order items from small business operators. When you register your child with the Ohio Amblyope Registry and the child is prescribed occlusion therapy, the Ohio Amblyope Registry will send the participating parents six (6) free boxes of adhesive eye patches, a $30.00 value. In addition, if the child wears glasses and cloth patches are acceptable to the eye doctor, the Ohio Amblyope Registry will send the parents, free of charge, two (2) cloth eye patches. The eye to be patch (left or right) must be specified when registering the child in order to receive the cloth patches. In addition to the free promotion patches, families with household incomes below the poverty level (2 times the federal poverty level guidelines for the family size), the child may be eligible for up to 30 boxes of adhesive patches free of charge. Click this line to learn more about the free patches program for low income families. Pirate patches are cloth patches that resemble those worn by a pirate. Pirate patches consist of a string or headband and eye patch which fits snuggly around the eye. Pirate patches are sometimes worn by older children who do not wear glasses and, as a consequence, cannot wear a cloth patch for glasses. Pirate patches are not recommended for young children because of the dangers of strangulation with the string or band that fits around the head. Sources for pirate patches are unknown, but such patches may be self-constructed. There are several limitations to pirate patches, particularly the ease at which children can peek around the patch and that the patch is not secured in place. Pirate patches also attract a lot of teasing from other children and one can only imagine the names associated with a child wearing a pirate patch…Aaarrrrrr mate. But in terms of cost, pirate patches are probably the least expensive type of patching. Some trial and error may be required to find the pirate patches or to construct pirate patches from scratch. Regardless of the type of eye patch used, it is very important to follow your eye doctor's patching instructions. Research has shown that parents often patch for less time than the eye doctors recommendations. It is very important to patch the prescribed time. Patching the eye for less time will reduce the chance for recovery of vision in the amblyopic eye. Caution is also advised in terms of patching the eye longer than the prescribed time. There is a condition known as "reverse amblyopia", also called "occlusion amblyopia" that occurs when the good eye is patched too long, particularly in a young child. In reverse amblyopia, the good eye becomes amblyopic and the original amblyopic eye may or may not be normal. So, follow your eye doctor patching directions and keep all eye doctor appointments.
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