Poor Vision
We use our vision to get around, learn new things and to meet other people and make friends. It is important to consider what your child’s particular problems with vision might be now and in the future.
If your child has been prescribed spectacles, contact lenses or a Low Visual Aid (LVA) it is important that they are encouraged to wear and use them. This will help your child see more clearly and ensure the vision parts of the brain grow and develop.
Problems at school may be due to some of the reading books being hard to see. This often means it takes longer and more effort to do the work. If the size of print is increased and letters and words spaced more widely most children will find schoolwork easier. Good bright lighting and crisp black print on a clean white background will also make things easier. Sometimes placing reading books on a slope, which tilts the print towards the child, will improve reading speed as well. When reading it can be helpful to read one line at a time through a ‘letter box’ placed over the page. Placing a piece of blue tack below the line they are reading, at the beginning of the next sentence, can help some children find their way back to the start of the next line more quickly.
Some children may also benefit from using a computer programme while reading. The programme only shows one word of a sentence at a time. The word is in the middle of the computer screen. This reduces the need for fast eye movements. It can increase reading speed and reduce tiredness. One programme is called ACE READER. There are many others. A demonstration can be downloaded from www.acereader.com. If you need any help with this please let us know.
It is also worth watching carefully to find out what the smallest toys are that a child can see and play with. Then try to only play with toys that are the same size or bigger. Placing one toy on a plain background will often help children see it more readily. Placing lots of toys of different size and colour close together on a patterned background can make them ‘invisible’ to many children with CVI.
Recognising facial expressions can often be difficult. It is worth trying to find out at what distance facial expressions can be seen and responded to. Then always try to talk and smile from within this distance. This helps a child to learn what facial expressions mean and to copy them. There is a special part of the brain that helps children ‘make sense’ of faces. Sometimes this part is also damaged. These children may have difficulty responding to smiling even if their vision is clear enough. If the child has visual field loss try to place objects in the part of the child’s vision that is working.
Cerebral Visual Impairment commonly occurs in children who have difficulty controlling both head and eye movements. Careful positioning of the head to prevent it falling to the side or falling forward can help a lot.
Infants and young children need to learn about the world around them. Home visiting teachers, physiotherapists and occupational and speech therapists may all add to the child’s care and education. It is important to continue the programmes that they recommend. If the child is involved in family activities vision can improve and new skills can develop.
Even if a child has very poor vision many useful and practical things can be done to improve the ability of the child to get around, interact with other children and learn.
Even if a child has very poor vision many useful and practical things can be done to improve the ability of the child to get around, interact with other children and learn.
Cortical visual impairment (CVI) occurs when there is damage to the visual cortex, or to the posterior visual pathways, or to both places in the brain. The eye generally does not have any internal damage although CVI can also be evident in children who do have ocular damage. The reduction of vision is due to neurological damage which hinders visual stimulation from being organized and interpreted by the brain. It is analogous to an imperfect computer chip which cannot fully process the input from the keyboard.
The diagnosis of cortical visual impairment can be made by an ophthalmologist and/or neurologist. The child should have a complete eye examination and a visual evoked potential (VEP) test. Children who are cortically visually impaired have a medical history that involves neurological impairment due to conditions such as asphyxia, cerebral hemorrhage, infection of the central nervous system, and/or trauma.
Dr. James Jan, a pediatric neurologist in British Columbia, has worked with children with a sight loss for over two decades. He has been involved with research in particular on the subject of cortical visual loss as it is a neurological based problem that results in visual impairment.
Just under 10% of the current population of visually impaired children in British Columbia are cortically visually impaired according to Dr. Jan. His practice has included many children with this diagnosis and he and his colleagues have made several observations about the “visual behaviors” associated with cortical visual impairment.
It is important to understand the base of information known about CVI must be analyzed to each child as an individual. Each characteristic of CVI may or may not fit an individual child. The information that does “fit” will help parents and teachers to design a home and/or school program that is tailored to each child’s needs. Dr. Jan’s and his colleagues at Children’s Hospital have noted the following behaviors associated with cortical impairment:
- Visual performance can be quite variable, simply put, some days are better than others. Visual functioning can even change from hour to hour with some children. Factors which might influence the fluctuation include: fatigue, noisy environments, illness, medications, seizure activity, and unfamiliarity of environment.
- Visual field defects may also be associated with CVI due to specific neurological damage.
- Movement cues, especially in the peripheral fields can often stimulate a visual response. Visual interpretation of the environment may be improved for some children when they are actually moving as opposed to standing still. Parents of some children with CVI have reported improved visual responsiveness when the child is riding in a car.
- Color vision does not seem to be affected. In fact, some colors appear to be “better received” that others such as red, orange, and purple.
The process of visual habilitation is in many ways different for the child with CVI than for the child who experiences an ocular impairment. The focus is for the CVI child to control visual input to avoid overstimulation. In view of the aforementioned characteristics of CVI, the following guidelines are recommended for consideration in home and/or school programming:
- Reduce extraneous sensory information from the child’s “working/playing environment”. Eliminate unnecessary noise or visual distractions. Present one item at a time as much as possible.
- The use of touch should be a primary means of introducing information. Continue to place the objects of daily care or “learning activities” in the child’s hand when presenting the item.
- Language is very important for information about the object or visual situation. Use labels that include description words. Tell the child what she/he is “seeing”. Voice intonation is important as far as providing meaning to a situation. When disciplining, for example, a firm voice should be used to match the words being used.
Familiarity is also an extremely important consideration. Parent and teacher experience has shown objects that are familiar often result in increased visual attention to that object as opposed to one that is new to the child. Think about what objects the child is involved with during his/her daily care activities. Make these objects part of his/her vocabulary (touch, function, sight). Examples might include:
- bottle/cup – drinking
- bowl/plate/spoon – eating
- comb – morning grooming
- washcloth or favorite bath toy – bathing
- music toy – bedtime
- diaper – diaper changes
- “security toy” – time to go somewhere outside of the home
Parents and teachers should decide what objects are typically used with the child during everyday activities or routines. To establish familiarity, the same object(s) should be used each time. The object should be visually, tactually, and verbally presented at the onset of the activity and then talked about as the child experiences their function. The exact style of presentation will vary according to each child’s general learning style and needs.
- The colors red and yellow are thought to be more readily perceived so may be used to enhance a visual target.
- Repetition is important for all children, practice is how they learn to integrate their new knowledge and put it to use. This especially is true for children who experience a sight loss.
- Be aware the child might fatigue easily in situations which require visual/auditory/tactile deciphering of information. Build in breaks and allow for extra response time before giving the child more information.
- Proper positioning is important for the child. If she/he is not in an aligned or supported body posture, the child cannot fully concentrate on the task at hand. This is true for all children, but especially important for the child with CVI and cerebral palsy. Consultation with a therapist should be utilized to promote optimal positioning.
- Each child’s family knows their child the best, their knowledge of what he/she likes, dislikes, etc. should be built into his/her learning activities