1. Chapter 6 Sensory Impairments: Hearing and Vision

2. Hearing Impairment
The Individuals with Disabilities Education Act (IDEA), formerly the Education of the Handicapped Act (P.L ), includes "hearing impairment" and "deafness" as two of the categories under which children with disabilities may be eligible for special education and related services programming.
While the term "hearing impairment" is often used generically to describe a wide range of hearing losses, including deafness, the regulations for IDEA define hearing loss and deafness separately.

3. Hearing Impairment
Hearing impairment is defined by IDEA as "an impairment in hearing, whether permanent or fluctuating, that adversely affects a child's educational performance."
Deafness is defined as "a hearing impairment that is so severe that the child is impaired in processing linguistic information through hearing, with or without amplification."

4. Deafness and Hearing Loss
Hard of hearing refers to a lesser loss, but one that nevertheless has a definite effect on social, cognitive, and language development.

5. Deafness and Hearing Loss (continued)
Types of hearing loss
Conductive hearing loss
A loss in the outer or middle ear
Sensorineural hearing loss
A loss in the inner ear (cochlea)
Central deafness
A loss in the higher auditory cortex
Combined loss
A loss in two or more of the above
Conductive hearing losses are caused by diseases or obstructions in the outer or middle ear (the conduction pathways for sound to reach the inner ear).
Conductive hearing losses usually affect all frequencies of hearing evenly and do not result in severe losses. A person with a conductive hearing loss usually is able to use a hearing aid well or can be helped medically or surgically.
Sensorineural hearing losses result from damage to the delicate sensory hair cells of the inner ear or the nerves which supply it. These hearing losses can range from mild to profound. They often affect the person's ability to hear certain frequencies more than others. Thus, even with amplification to increase the sound level, a person with a sensorineural hearing loss may perceive distorted sounds, sometimes making the successful use of a hearing aid impossible.
A mixed hearing loss refers to a combination of conductive and sensorineural loss and means that a problem occurs in both the outer or middle and the inner ear.
A central hearing loss results from damage or impairment to the nerves or nuclei of the central nervous system, either in the pathways to the brain or in the brain itself.

6. Deafness and Hearing Loss (continued)
Causes and prevention
Conductive hearing loss can occur from frequent ear infections.
It can usually be aided by amplification systems.
Sensorineural hearing loss and central deafness are caused by malformation of the ear or severe infections.
A cochlear implant may be needed.

7. Cochlear Implant
Cochlear implants are devices that take the place of damaged inner ear structures that cause profound hearing loss.
In the past, profound hearing loss was commonly referred to as nerve deafness.
This was incorrect because the problem was often not with the hearing nerves, but with the hair cells that line the cochlea.
The cochlea is the spiral part of the inner ear containing nerve endings that carry information about sound to the brain.
Cochlear Implants are benefiting thousands of severely or profoundly deaf adults and children who have viable neurons in the inner ear that can respond to direct electrical stimulation. These electrical devices deliver sound to the inner ear, bypassing the damaged hair cells to deliver rich auditory impulses directly to the auditory nerves. Cochlear implants help patients hear, improve their understanding of speech and improve their speaking ability.
Three Components
Headpiece- Worn externally behind the ear like a hearing aid, the headpiece has a microphone where sound enters and travels down a cable to a speech processor.
Speech Processor- A small box worn in a pocket or on a belt changes the sound from the microphone into an electrical code and sends the code back up into the headpiece. Most patients now choose to wear a miniature speech processor behind the ear like a hearing aid.
Implantable Receiver- Surgically placed within the cochlea, the implantable receiver takes the electrical code and sends it through tiny wires to the inner ear to directly stimulate the hearing nerve fibers.
The brain adapts to give the person what sounds like almost normal speech. While the result does not fully reproduce normal sound, the device filters out background noise and is good for person-to-person conversation.
The three major types of cochlear implants are available: the Nucleus, Clarion and Med-El devices. The surgical procedure generally lasts about 2 hours. The team helps each patients choose the most appropriate device.

8. Cochlear Implant
A cochlear implant (bionic ear) is a surgically implanted device for the hearing-impaired. It is the first medical technology able to functionally restore a human sense - hearing.
Unlike a hearing aid that amplifies sound to make it loud enough for an impaired ear, a cochlear implant bypasses the damaged area and sends sound signals directly to the auditory nerve. A cochlear implant consists of an internal and an external component.

9. Cochlear Implant
The Internal Component has two main parts (neither are visible from the outside):
A receiver-stimulator [3] placed under the skin behind the ear
An electrode array [4] sitting within the inner ear
The External Component has two main parts:
A speech processor [1] which may be worn behind the ear or on the body
A transmitter coil [2]

10. Deafness and Hearing Loss (continued)
Warning signs
Tugs on ears
Used to talk and respond and now does not
Drops initial consonants
Seems inattentive
Looks confused when given directions
Turns head to one side to hear better

11. Deafness and Hearing Loss (continued)
The impact of hearing loss on development
Effect on language development
A child who cannot hear sounds during the critical period may never master those sounds.
Language delays are probable.
Parents and caregivers may stop speaking to the child, because he or she cannot hear them.

12. Deafness and Hearing Loss (continued)
Effect on cognitive development
Language and cognitive skills go hand in hand.
If children are behind in language skills, they are more than likely going to be delayed cognitively as well.
Children with little or no hearing tend to be years behind their normally developing peers.

13. Deafness and Hearing Loss (continued)
Effect on social development
Shy and withdrawn categorize this child.
These children tend to be socially immature.
They also tend to be impulsive and hyperactive.
Unintentionally, they are often left out, because hearing is so much a part of our world.

14. Deafness and Hearing Loss (continued)
Effects on family life
Frustration
Lack of time to learn new methods
Need for behavior management
Family therapy and counseling

15. Deafness and Hearing Loss (continued)
Methods of communication
Speech reading—child learns to read your lips while you talk
Cued speech—a system of hand shapes and mouth movements in which the child learns the combinations to understand the spoken word

16. Deafness and Hearing Loss (continued)
American Sign Language—a language that consists of hand movements with or without speaking
Signed English
Finger spelling
Total communication—combines speech and hand motions

17. Deafness and Hearing Loss (continued)
Which method?
It is family preference.
No one method has been proven to be the best.
Total communication leads to more communication with the outside world.

18. Deafness and Hearing Loss (continued)
Early intervention
As with all disabilities: The earlier intervention is begun, the better.
Children need to learn to use what residual hearing they have.
They need to exercise their vocal chords for speech.

19. Deafness and Hearing Loss (continued)
Guidelines for teachers
Get down on the child’s level.
Sit close to the child when talking.
Make eye contact.
Use short, simple sentences.
Use concrete examples.

20. Amplification devices
Hearing aids—an amplification device is molded to fit the child’s ear.
Problems: bad fit, dead batteries, feedback, on and off switch, sore ears

21. Amplification devices
FM system—child wears a receiver and the teacher wears the microphone.
Problems: dead batteries, on and off switch

22. Blindness and Vision Impairments
Blind—visual loss is severe enough that it is not possible to read print.
Low vision—residual vision is sufficient to allow a child to read large print or possibly regular print under special conditions and to use other visual materials for educational purposes.

23. Blindness and Vision Impairments (continued)
Total blindness is the inability to distinguish between light and dark.
Most children can see some light and shadows.

24. Visual Impairment
"Partially sighted" indicates some type of visual problem has resulted in a need for special education;
"Low vision" generally refers to a severe visual impairment, not necessarily limited to distance vision. Low vision applies to all individuals with sight who are unable to read the newspaper at a normal viewing distance, even with the aid of eyeglasses or contact lenses. They use a combination of vision and other senses to learn, although they may require adaptations in lighting or the size of print, and, sometimes, braille;
"Legally blind" indicates that a person has less than 20/200 vision in the better eye or a very limited field of vision (20 degrees at its widest point); and
Totally blind students learn via braille or other non-visual media.
Visual impairment is the consequence of a functional loss of vision, rather than the eye disorder itself. Eye disorders which can lead to visual impairments can include retinal degeneration, albinism, cataracts, glaucoma, muscular problems that result in visual disturbances, corneal disorders, diabetic retinopathy, congenital disorders, and infection.

25. Blindness and Vision Impairments (continued)
Types of vision problems
Physical abnormalities
Cataracts
Glaucoma
A cataract is a clouding of the normally clear lens of the eye. Normally, light enters your eye via the pupil and passes through the lens which focuses it onto the retina. If there is an opacity in the lens, the result is hazy or blurred vision. How blurry or hazy depends on the characteristics of the cataract.
All adults, sooner or later, will develop cataracts. This is common with aging. However children can also be affected. Occasionally an infant is born with a cataract. Some of these cataracts are inherited. Some are the result of infections contracted during pregnancy. Most of the time, however, the cause of the cataract remains unknown.
Some childhood cataracts are small enough or not dense enough to cause serious problems. Many childhood cataracts, unfortunately, require surgery. Often this surgery must be performed during the first month or two of life if the infant is born with a significant cataract. If not done during this time frame, untreatable amblyopia may occur and the child will have extremely poor vision for the rest of his or her life. Sometimes, again depending upon the characteristics of the cataract, surgery can be delayed until the child is older. With prompt diagnosis and treatment, cataracts in children can be successfully managed and what used to be a cause of blindness now can be eliminated.
Glaucoma is a leading cause of irreversible blindness throughout the world. The visual loss in patients with glaucoma results from damage to the optic nerve that carries sight from the eye to the brain. Although it most commonly affects the elderly, glaucoma occurs in about 1 in 25,000 babies born in the United States. In both adults and babies with glaucoma, the prevention of permanent blindness requires detection and proper treatment. Glaucoma that occurs in infancy and early childhood differs from most adult glaucoma in several ways. Because it is rare, most patients need to travel to a specialized medical center for treatment. Also, childhood glaucoma is usually treated with immediate surgery rather than with medication or laser. Infants who receive prompt surgical treatment will do well; 80 to 90% will have normal or nearly normal vision for their lifetime. Most babies who have glaucoma and cannot obtain specialized care quickly will lose their vision. Early detection and treatment means the difference between sight and blindness.

26. Blindness and Vision Impairments (continued) Physical abnormalities
Retinopathy of prematurity
Cortical blindness (Neurological Visual Impairment or Cortical Visual Impairment)
What is Retinopathy of Prematurity?
Retinopathy of Prematurity (ROP) is a developmental disease of the eye that affects premature infants. When a baby is born, the retinal blood vessels have not completed their development. In patients with ROP, the blood vessels stop growing and new, abnormal blood vessels grow instead of normal retinal blood vessels. The developmental arrest and blood vessel maldevelopment may be temporary or permanent, minimal or severe. The most severe complication of this disease is bilateral blindness in early childhood. Who gets ROP? Almost all infants with advanced stages of ROP weighed less than 1,600 grams (about three pounds, eight ounces) at birth. Many required significant use of additional oxygen to stay alive. Some of these babies also suffered from severe infections, lung disease, anemia, hemorrhages in the brain, and a variety of other serious problems. Most babies with advanced ROP were born before 32 weeks of gestation. The smaller the baby or the more immature the retinal development, the more likely the infant is to develop complications of ROP which can lead to blindness. Infants under 1,000 grams (about two pounds, three ounces) are the most likely to develop severe ROP Although excess oxygen has been shown to constrict blood vessels and therefore plays a role in initiating the disease,
NVI occurs when the part of the brain that is responsible for seeing is damaged. In other words the eye itself is normal, but the brain does not process the information properly. Cortical blindness is the total or partial loss of vision in a normal-appearing eye caused by damage to the visual area in the brain's occipital cortex.[1]

27. Blindness and Vision Impairments (continued)
Visual acuity problems
Refractive errors
Astigmatism: uneven refraction
Myopia: nearsightedness
Hyperopia: farsightedness

28. Blindness and Vision Impairments (continued)
Identifying vision problems
This is rather difficult until a child is in school.
A few tests are available for the younger child
Snellen Illiterate E
Teller Acuity Cards
Photo Screening
Children often do not know they have a problem, because they do not know what they are looking at.

29. Blindness and Vision Impairments (continued)
Muscular abnormalities
Strabismus: eyes are not aligned (crossed eyes)
Amblyopia (lazy eye):
Nystygmus
Amblyopia is poor vision in an eye that, for various reasons did not develop normal vision during early childhood. When one eye develops good vision and the other does not, the eye with poor vision is called amblyopic. Amblyopia occurs in about 2-3% of the population and can only be treated in childhood, preferably before 7 years of age. It is because of this possibility of developing amblyopia (for which there are no outward signs) that Dr. Kronwith believes all children should be examined by a pediatric ophthalmologist by 4 years of age. At this age there can still be enough time to reverse the amblyopia before the child is too old.
The major causes of amblyopia are strabismus and unequal focusing of the eyes.
Strabismus can cause amblyopia since when one eye is not aligned, the brain, which does not want to experience double vision, will shut off the image in the deviating eye. This prevents the development of the cells and nerves which enable that eye to see.
Unequal focusing of the eye is the other major cause of amblyopia. If each eye has to focus a different amount to see clearly, the brain, which cannot focus each eye a different amount, will chose one eye to focus and the other will remain out of focus. The unfocused eye does not develop normally and amblyopia occurs. It is this form of amblyopia that is most difficult to diagnose since the eyes may be perfectly straight and there are no complaints from the child since there is excellent sight in one eye. Diagnosing this condition requires dilation of the pupils and examination of the inside of the eye with special instruments. Parents are often shocked to learn that their child has amblyopia in this situation, especially when the child is too young to read the eyechart. However, the doctor can, by examining the inside of the eye, diagnose amblyopia even without the child reading an eyechart! This is again why all children should be seen by 4 years of age, earlier if there is a family history of amblyopia.
The treatment of amblyopia almost always requires the patching of the good eye combined, often, with glasses. The glasses will correct the error in focusing but this is often not enough and the better eye must be patched in order for the brain to be forced to use the amblyopic eye and develop the cells and nerve connections necessary for excellent sight in that eye. Amblyopia is usually treated first before correcting any associated strabismus.
If amblyopia is not treated, the child will permanently have a poor seeing eye. This will cause many problems in the future including lack of depth perception and the fear, that if anything should ever happen to the good eye, the child will be left with poor or no vision in both eyes. We understand that most children hate to have their eyes patched, especially when they depend upon that good eye to see. As the parent, it is incumbent upon you to make sure the child does what is best for him or her and the success or failure of the treatment mostly depends upon your interest and involvement, as well as your ability to gain your child's cooperation. Dr. Kronwith will go over various methods to aid you.
With early detection and treatment, amblyopia is usually reversible and excellent vision is obtained.
Nystagmus is an involuntary rhythmic shaking or wobbling of the eyes.

30. Blindness and Vision Impairments (continued)
Identifying vision problems
This is rather difficult until a child is in school.
A few tests are available for the younger child
Snellen Illiterate E
Teller Acuity Cards
Photo Screening
Children often do not know they have a problem, because they do not know what they are looking at.
The Teller Acuity Cards and Teller Acuity Cards II™ offer eye care practitioners and vision researchers a rapid and reliable method of assessing visual acuity in infants, children, and nonverbal adults. The set of seventeen cards allows clinicians and researchers to measure an infant or child's ability to resolve black and white striped patterns printed on the cards. Teller Acuity Cards® II can test for pediatric visual acuity without requiring a verbal response. By judging an infant's attention to a series of cards showing stripes of different widths, the vision screening professional can perform accurate infant vision screening and avoid the complex, time-consuming laboratory testing that would otherwise be necessary
What is photoscreening? Photoscreening is a tool for screening the eyes of pre-verbal or challenged children. During a photoscreening, the screener uses a special camera to take a picture of the child's eyes. Once the instant photo is developed, the photos are sent to a trained optometrist or ophthalmologist who analyzes the photo to look for signs of vision problems.

31. Blindness and Vision Impairments (continued)
Warning signs
Rubbing eyes
Closes one eye
Watery or itchy eyes, not allergy related
Inability to see, squinting
Blurred vision

32. Signs of Vision Problems
Holding a book very close (only 7 or 8 inches away).
Child holds head at an extreme angle to the book when reading.
Child shuts or covers one eye; tilts head, thrusts it forward.
Child squints, squeezes eyelids together, frowns.
Child blinks excessively or becomes irritable when doing close work.
Child is unable to see distant things clearly.
Child has crossed eyes or eyes that each turn outward.
Child has red-rimmed, encrusted or swollen eyelids
Child has recurring sties
Child has itchy, burning, or scratchy feeling eyes.

33. Blindness and Vision Impairments (continued)
The impact of vision problems on development
Effects on language development
Child cannot see objects, so they have trouble learning the meaning of the spoken word.
Children must be given time to explore concrete objects to learn meaning.
Teacher must develop the use of descriptors.

34. Blindness and Vision Impairments (continued)
Effect on cognitive development
Delays due to language development problems
Usually catch up by six years of age
Effect on motor development
Children will be delayed because they cannot see objects to reach for them.
Children are also afraid to move because they cannot see what is in front of them.

35. Blindness and Vision Impairments (continued)
Effect on social development
The children tend to be quiet and passive.
They do not make facial expressions when people talk to them.
Often they do not even turn toward the sound.

36. Blindness and Vision Impairments (continued)
Early intervention programs
Orientation and mobility training
This is a must.
It exposes the children to their environment.
If things are not moved often, the children can learn independence at play and cleanup.

37. Blindness and Vision Impairments (continued)
Teaching children with vision loss
Take advantage of their other senses
Concrete objects
Descriptions of objects
Rich vocabulary

38. Blindness and Vision Impairments (continued)
Guidelines for teachers
Use words for everything.
Be specific.
Let the children discover through touch.
Put different textured fabric at each center, identifying the boundaries.
Make use of their residual vision:
Write words extra large and in bold colors.