WHAT IS VISION IMPAIRMENT?
Vision impairment refers to the inability use eyesight by the usual means. Since vision impairment is a broad term, it can include very low vision, inability to see certain colors (colorblindness), or no vision (complete blindness).
In the human anatomy, the eyes and brain work together to create eyesight. The eyes are composed of many small parts, including the cornea, iris, lens, and retina. Each part coordinates to capture and focus on light and images. The parts also contain nerve endings that send signals to the brain, allowing the brain to recognize and process these images. Processing also creates different aspects of eyesight like field of vision, central acuity, and peripheral vision.
For people with usual vision, the sight process happens instantaneously. If the process does not work as it should, however, a person will have vision impairment or blindness. A person can be visually impaired in one or both eyes.
What are Common Types of Visual Impairment?
There are different types of vision impairment that affect children. Since vision is one of the five major senses that affects learning, sensory processing, and play, parents who suspect vision impairment in their children should address it immediately.
- Amblyopia – Also known as “lazy eye,” amblyopia occurs when the eye cannot sustain visual acuity even with the help of prescription eyeglasses. Amblyopia usually begins in infancy or early childhood and can affect one or both eyes.
- Coloboma – Coloboma occurs when part of a structure within the eye (such as iris, retina, choroid, or optic disc) is missing. Doctors usually diagnose coloboma at birth, and it can be the result of a genetic mutation or fetal alcohol syndrome.
- Congenital Cataracts – This condition occurs when the lens of the eye is cloudy at birth.
- Cortical Visual Impairment (CVI) – CVI refers to decreased visual response neurological problems in the region of the brain that controls vision (rather than any structural problems with the eyes themselves)
- Blindness – Children are legally blind if they cannot see at 6 m of what children with typical vision can see at 60 m. Similarly, children are legally blind if their field of vision is less than 20 degrees in diameter (the standard field of vision for people with normal eyesight is 180 degrees).
- Color Blindness – Characterized by the inability to see certain colors, color-blindness occurs when one of the three cone cells in the retina does not function properly. Red-green color blindness is the most common and affects the ability to distinguish between greens, browns, reds, and oranges. Blue-yellow color blindness is less common and refers difficulty distinguishing yellows and blues. Although color blindness is not considered a serious impairment, its diagnosis is very important since undiagnosed color blindness can impact a child’s early performance in school.
- Farsightedness (Hyperopia) – This condition refers to an impaired ability to see nearby objects. People are called “far sighted” when they see better at a distance or when objects are “far away.”
- Nearsightedness (Myopia) – This condition refers to an impaired ability to see far away objects. The farther objects are away, the blurrier vision becomes. People are called “near sighted” when they see objects better when the items are close by.
- Optic Nerve Hypoplasia – A congenital medical condition caused by underdeveloped fibers in the optic nerve. This condition may result in sensitivity to light and problems with depth perception or sharpness of vision.
- Retinitis Pigmentosa – This inherited disorder is caused by the gradual breakdown of the retina. Problems include decreased night vision and impaired side or peripheral vision. Most people with retinitis pigmentosa are declared legally blind and need additional assistance.
- Retinopathy of Prematurity (ROP) – ROP refers to abnormal or insufficient development of light-sensitive retina blood vessels in infants born prematurely.
- Strabismus – This condition refers to the inability of both eyes to focus on a single object simultaneously. Commonly the result of inadequate eye muscle control, the condition can cause one or both eyes to appear “crossed” instead of looking in a single direction.
- Very Low Vision – Low vision is a general term for children who cannot see everything as expected for their age. It can include blurred vision or impaired side vision (peripheral vision).
SIGNS, CAUSES & EFFECTS
What are the Signs of Vision Impairment in Children?
Although some conditions like coloboma and strabismus may be easier to notice right away, other conditions may be harder to detect at first. Most parents tend to notice signs in a child’s behavior that indicate there may be an issue with his or her vision.
Signs of vision impairment in babies may include the following:
- Infant does not focus on faces or objects by 4-5 weeks of age
- Infant has not focus and smile at familiar faces by 6-8 weeks of age
- Eyes do not move together to follow a face or object
- Eyes appear to “jerk” and move rapidly or randomly from side to side (nystagmus)
- Eyes do not react to changes in light (such as a light switch turning on
- Pupils appear cloudy instead of black
- Eyes appear to bulge
Signs of vision impairment in toddlers or older children may include the following:
- Repeated shutting or covering one eye with hand
- Unusual degree of clumsiness (such as accidentally knocking items over)
- Holding books or toys too close to face; squinting to see toys
- Sitting too close to TV or other screens
- Avoiding play or learning activities that require good vision
- Frequent blinking or eye rubbing (particularly in settings with low lighting)
- Frequent tiredness during activities that require up-close vision (like reading, coloring, or handheld games)
- Tilt or turn head often when trying to see things up close
What Causes Vision Impairment in Children?
Many vision problems can develop before a child is born. For example, imperfections can occur in the development of the eyes, or structural problems can occur in the parts of the brain that processes vision. In addition, visual problems can be inherited (genetic) or the result or an illness, infection, or injury at birth.
What are the Some of the Effects of Vision Impairment in Children?
If you notice signs of vision impairment in your child, it is important to address these issues immediately. As one of the five major senses, eyesight affects much of the sensory processing that occurs in a child’s world. Children with major vision impairment will need to work with specialists to learn how to use other senses (such as sense of touch with hands or the sense of hearing) to navigate their worlds. Even for moderate to severe vision impairment, early intervention can help a parent sort through options (such as special devices or computer programs) that can assist children who have problems with eyesight.
Without help for vision impairment, children might struggle in some of the following developmental areas:
- Communication (such as the inability to make eye contact)
- Playing and Socializing (such as inability to read non-verbal cues or the feeling of being “lost in a crowd”)
- Speech (eyesight can affect the ability to point out objects and thereby learn object names)
- Time (light perception problems can make it harder to learn the difference between day and night)
- Motor Skills (vision impairments can result in clumsiness and affect motor abilities)
- Reading and writing (children may feel fatigued and less motivated to practice these skills)
How Can I Help My Child with Vision Impairment?
Fortunately, there is a wealth of opportunity for helping your child with vision impairment. The first step is to consult with a pediatrician for an eye checkup. The pediatrician may also refer you to a pediatric ophthalmologist for a final diagnosis.
After getting the right diagnosis, children with any level of (vision impairment can benefit extraordinarily from early childhood intervention (ECI) and individualized education programs (IEP).
These programs can feature a team of trained specialists that support your child’s development, including orientation and mobility specialists, occupational therapists, physical therapists, and special education teachers. Each session provides your child with the tools needed to gain greater independence and navigate the world of learning and play. Program specialists may also be able to refer you to the latest technology and computer programs that can also help supplement your child’s activities.
Since many vision impairments are classified as disabilities, it is also important to register for the necessary disability benefits or funding. The purpose of this funding is to support your early intervention efforts or equipment.
Contact the Warren Center for additional information about early childhood intervention for vision impairment.