Visual Impaired

Visual Impaired

Definition

Blindness is the inability to see from light to dark or just the inability to see at all. In some cases it leads to total loss of vision. Visual impaired is a severe reduction of vision that can’t be fully treated by medical treatment or lenses. Blindness and visual impairment are often used as synonyms, in the sports world. The International Blind Sports Association (IBSA) and the U.S. Association for Blind Athletes (USABA) serve persons whose vision varies from 20/200 ft to total blindness after corrections made by glasses. About 285 million people are visually impaired worldwide; 39 million are blind and 246 have low vision. Proper training, specialized equipment, and opportunity will help make life easier for individuals with blindness and visual impaired.

Varying Levels/Classifications

There are three sport classifications, which are based on a Snellen chart measure of acuity and assessment of field vision. Visual acuity is sharpness of vision and acuteness of the vision determined by a comparison with the normal ability to define certain letters at a give distance. Field of vision refers to the area within which object can be seen when the eyes are fixed straight ahead. A severely limited field of vision is called tunnel vision. To comprehend field of vision, look through a straw that is equivalent to a 5° field of vision. Most people have a field of vision of about180°.

B1 Classification – no light perception in either eye up to light perception and inability to recognize the shape of a hand in any direction and at any distance.

B1 encompasses two education classifications: Total Blindness (lack of visual perception). Inability to recognize a strong light shown directly into the eye.

Light Perception (less than 3/200). Ability to distinguish a strong light at a distance of 3 ft. from the eye, but inability to detect movement of a hand at the same distance.

B2 Classification – Ability to recognize the shape of a hand up to a visual acuity of 2/60 and/or a limitation of field of vision of 5°.

B2 encompasses two educational classifications: Motion Perception (3/200 to 5/200). Ability to see at 3 to 5 ft what the normal eye at 200 ft. This ability is limited almost entirely to motion.

Travel Vision (5/200 to 10/200). Ability to see at 5 to 10 ft what the normal eye sees at 200 ft.

B3 Classification – 2/60 to 6/60 (20/200) vision and/or field of vision between 5 and 20°

B3 is the same as legal blindness, the minimal disability condition specified by the law that permits special services: Legal Blindness (20/200). Ability to see at 20 ft what the normal eye sees at 200 ft. (i.e., 1/10 or less of normal vision)

Cause(s) of disability

Blindness can occur as a result of number of infectious noncommunicable diseases, as well as injuries. The leading causes of vision impairment and blindness in the United States are age-related eye diseases. In older persons, cataracts and diabetes are the leading causes. Other eye disorders, eye injuries and birth defects can also cause vision loss. The most common causes of blindness include:

Diabetic Retinopathy: Within 10 years of the onset of diabetes, 50% of individuals develop diabetic retinopathy, which is caused from gradual damage to the retina.

Glaucoma: A condition in which the pressure inside the eyeball rises to a point where it damages the optic nerve, first affecting peripheral vision and later causing central vision blindness.

Trachoma: Symptoms begin 5 to 12 days after being exposed to bacteria Chlamydia trachomatis. The condition begins slowly as the tissue that lines the eyelid becomes inflamed, which if untreated may lead to scarring. If the eyelids are severely irritated, the eyelashes may turn in and rub against the cornea. This may cause eye ulcers, additional scars, vision loss, and blindness.

Cataracts: Clouded or opaque spots on the lens that gradually increase in size and diminish vision, particularly in low-light conditions. Fortunately, cataracts can be easily removed through surgery.

Retinopathy of Prematurity (ROP): Occurs when oxygen is poorly regulated in incubators, which can cause excessive oxygen to damage the retina and sometimes mild brain damage can occur.

Retinal Detachment: A break or tear in the retina, which can cause visual impairment. The retina, or inner lining of the eyeball, is an expansion of the optic nerve that contains the sensory receptors for the light rays.

Retinitis Pigmentosa: Another cause of blindness can occur from retinitis pigmentosa, which is an inherited disease that causes progressive degeneration of the retinal cells. The degeneration gradually decreases the field of vision, eventually causing tunnel vision and night blindness. This condition occurs most in children and adolescents.

Albinism: About 4% of visual disorders in children are caused by a genetic disorder called albinism, which causes a congenital absence of pigment in the skin, hair, and eyes.

Corneal Opacity: Is a disorder of the cornea, the transparent structure on the front of the eyeball, which can cause serious vision problems. Corneal opacity occurs when the cornea becomes scarred. This stops the light from passing through the cornea to the retina and may cause the cornea to appear white or clouded over.

Coloboma: A birth defect that causes a cleft in the pupil, iris, lens, retina, choroid, or optic nerve. It can result in reduced acuity and felid loss if the damage extends to the retina.

Onchocerciasis: An infection caused by the nematode Onchocerca volvulus. Humans acquire onchocerciasis through the bite of Simulium blackflies. Because the fly develops and breeds in the flowing water, onchocerciasis is commonly found along rivers and is sometimes referred to as river blindness.

Optic Nerve Atrophy: Damage or degeneration to the optic nerve, which carries visual signals to the brain. Vision loss will be dependent on the amount of damage, but may include blurred vision, poor color and night vision, and light sensitivity.

Optic Nerve Hypoplasia: Underdevelopment of one or both optic nerves, resulting in a small optic nerve and visual impairment. The degree of visual impairment varies significantly, but there is usually an acuity loss. Optic nerve hyperplasia may be associated with other conditions.

Cortical Visual Impairment (CVI): A complex and heterogeneous condition in which the eyes and optic nerves appear healthy; yet, patient does not have normal vision or normal visual perception. Cortical visual impairment is not caused by any condition of the eye. Rather, it is due to damage to the visual cortex of the brain or the visual pathways which results in the brain not adequately receiving or interpreting visual information. Intracranial bleeding, head trauma, birth defects, strokes, and seizures, among others can result in cortical visual impairment.

Motor Characteristics related to disability

Motor development is delayed in blind infants, particularly in mobility and locomotion related behaviors. Mastery of motor milestones is in a different order from that of sighted infants; also milestones that require vision for motivation are prolonged the most. Such as raising the head from prone, reaching, crawling, creeping, and walking. Object control and manipulation tend to be delayed 3 to 6 months. Therefore, proper emergence of tactile perception abilities and related problem-solving skills are prevented. Early intervention is beneficial but does not fully remediate delays. Cooperative play is needed to fully exceed visually impaired children from the lack of awareness of other kid’s presence. In general, persons with partial sight perform better than those with total blindness. Visual impairment is typically designated as congenital (born with) or adventitious (diagnosed at age 2 or 3 or later). Congenital impairment is often not recognized until motor or cognitive delays appear. Age of onset should always be indicated due to the fact that it gives insight into the amount of time the student had for developing space and form perception, visualization skills, and locomotor and object control patterns. It is imperative that individuals with visual impairment are placed in an effective exercise program to prevent the following to worsen:

Decrease Postural Tone • Especially in the shoulder girdle and pelvis • Caused by impact of vision loss on early sensory experiences and the development of reflex activity • The trunk and extremities are also often affected • Optical head righting • Labyrinthine righting (righting of head and neck based on gravity) • Equilibrium responses

Problems with Gait • Feet wide • Pelvis rotated forward • Often exhibit exaggerated weight shift because of proprioceptic problems • Deviation of the head from midline

Shoulders, Arms, and Hands • Poor proximal control • Weakness of arms and hands • Decreased grasp strength • Delayed development of pincer grasp • Poorly developed arch of the hand due to lack of weight bearing and manipulation of objects

Legs and Feet • External rotation from the hip • Widened base of support

Positioning • Stability is critical to efficient visual functioning • Especially true of the should girdle

Flickering • Causes EEG changes that either calm or excite the central nervous system • Those with injuries or disease processes closer to the brain exhibit more mannerisms.

Cognitive characteristic related to disability

Vision is a key sense to helping us through our daily life, visual impairment challenges one to learn to use other key sensory receptors to adapt to a different lifestyle. Using other senses, will help achieve everyday life by helping overcome challenges such as communication, here are some of the deficiencies:

Sensory Integration • Learning to use all of the senses to form a meaningfully whole interpretation of the environment

Communication • Vision enables us to perceive objects in their totality and in context. Severely visually impaired children have to rely on sequential observation. They can see or touch only part of an object and from this limited information build up an image of components • Based on the different conceptualization of the environment, blind children may follow alternative paths of language development. The use and nature of language differs in non-verbal patterns of communication, loudness, posture, smiling and other facial expressions, and their reliance on formulaic and standard expressions.

Memory & Attention • Smaller than normal capacity • Inability to retrieve information • Limitations in storage and retrieval ability • Absence of rehearsal skills to get into long term memory

Perception • Sensation with meaning • Unable to utilize inductive and deductive thinking • The sensory preferences of infants changes from tactile to visual

Social characteristics related to disability

Overemphasis on Academic: Reading and other academic skills require more time than average for individuals with visual impairment. As a result, such children often spend time in studying that others use for leisure and physical activity. This not only deprives them of skill and fitness but also interferes with making and keeping friends. With age, deficits in social competence become more and more obvious. Unless helped with social development, the life experiences of people with visual impairment differ considerably from those of peers. This eventually may interfere with job success. Most jobs are lost, not because of inadequate vocational skills, but because of inability to get along with other workers.

Stereotyped Behaviors and Appearance: Stereotyped behaviors are mannerisms like rocking backward and forward, putting fist or fingers into eyes, in front of face, whirling rapidly round and round, and bending the head forward. These behaviors can be minimized or prevented through vigorous daily exercise. Verbal correction often causes anxiousness and self-consciousness. A good approach is to agree on a tactile cue like a hand on the shoulder as a reminder to stop. People with visual impairment should be taught self-monitoring in relation to appearance, postures, and facial expression. Visual impairment limits ability to imitate, thereby spontaneous learning appropriated behaviors and responses as do sighted persons.

Health problems related to disability

Stress: Most visually impaired persons will feel stress in new and unfamiliar situations, particularly when they feel isolated from peers. Being left out and feeling like an outsider may cause them to feel this way. It’s best to foster them and make them feel welcomed. Especially if they are new kids entering a new school, it’s best to encourage the child to be open with his feelings.

Depression: Usually the stress for persons with VI leads to depression. Also just the fact of having your vision lost leads to depression. Its best to have individuals be open to their feelings and create a healthy environment instead of bringing them down.

Program guidelines and principles At least 80% of people who are blind have some residual vision. Given good light conditions to use residual vision, their sport performances is similar to that of sighted peers when instruction and practice are equal. They are at a disadvantage at night or during rainy days so its best to schedule practices during the day. The following guidelines will help facilitate interactions with people with VI in social and instructional settings: 1. When starting and interaction, always state your name. Do not expect to be recognized by the sound of your voice. This is especially important in noisy settings. 2. Ask if help is need with mobility. Do not grab the person’s arm. The appropriate protocol is for the person with VI to grasp your upper arm and walk with you, side by side, unless the passage is to narrow. Give verbal cues, indication steps. Changes in surface, and doors to be opened. 3. When suggesting places to go, indicate the anticipated levels of noise. When the goal is conversation, select quiet setting where you can be heard. 4. When serving food, indicate the location of food on the plate such as meat at 12 o’clock, Provide bread or a cracker to be used as a pusher. 5. When providing learning material, ask whether the person prefers large print, Braille, or audiotapes. Also its best to check technology offered by your library or other nearby resources in terms of specially designed computers that can read print and speak.

Instructional techniques and activities

B1 Classification: B1’s do some sports such as swimming, judo, and wrestling independently. In track events, they typically run side by side with a guide. The athlete maintains contact with guide by means of a tether, which is usually a rope no more than 50 cm in length, held by each by the inside hand. In snow skiing, a longer tether allows a person who is blind to follow his or her guide. In water skiing, the rope between the boat and the skier serves as the tether.

B2 Classification: B2s can do many activities independently when the sunlight or indoor lights are bright. In track events, they have the option of running independently or using a guide. Tethers are optional; typically B2s wear thick glasses and can read large print with the aid of magnifying devices.

B3 Classification: B3s do not use guides, but they might require verbal assistance during night or low-vision conditions. They wear thick glasses and can read large print without magnifying devices. Others can read regular-size print by placing their faces very close to the page.

Guidewire Activities Students with visual impairment and blindfolded friends should be provided with a guidewire stretched from one end of the playfield or gymnasium to the other to enable them to meet such challenges like “run as fast as you can.” Students can hold onto a short rope looped around the guidewire (gliding fingers directly over the wire can cause burns). Window-sash cord stretched at hip height is probable best for running practice. A knot at the far end of the rope warns the runner of the finish line. The purpose of the guidewire is to build self-confidence in independent travel.

Spatial Awareness and body Image activities In spatial awareness training, objective are tactile identification of objects, orientation to stable and moving sounds, spatial orientation, improvement of movement efficiency, and mobility training. Children need special training in recognizing the right-left dimensions of objects that are facing them. Children must be provided with opportunities for learning about their own body parts. Three-dimensional figures must be available to teach similarities and differences between different body builds, male and female physical characteristics, and postural deviations.

Sound Usage Activities Students with VI can be grouped with individuals who have auditory perception deficits for special training in recognizing and following sounds. There should be a progression from simple to difficult to develop. Once success is completed, students should be exposes to several different sounds, with instructions to pick out and follow only the relevant one.

Orientation and Mobility Training Comprehensive physical education programs include units on orientation and mobility. Many children with VI are usually overprotected prior to entering school and may need immediate help adjusting to travel with school environment. Appropriate goals for children with VI are to demonstrate functional movement skills in safe play with one or more friends on playground equipment.

Haptic Perception Teaching Model Haptic perception refers to the combined use of tactile sensations and kinesthesis. When planning movement exploration activities, the physical educator must realize that space is interpreted unconventionally by haptic-minded persons. Whereas the visually oriented child perceives distant objects as smaller than those nearby, the child with VI does not differentiate between foreground and background. Size of objects is not determined by nearness and farness, but rather by the objects emotional significance and the child’s imagination. Having no visual field to restrict them their space is as large as their imagination. However, they tend to think in parts rather than wholes since concepts are limited to the amount of surface they can touch at any given time. Miniature figures can be arranged on the simulated playground to acquaint students with playing positions, rules, and strategies. Dolls can also be used to teach spatial relationships among dancers in a group composition, cheerleader in a pep squad demonstration, and swimmers in the assigned lanes of a meet. An understanding of national and international sport opportunities gives insight into programming for individuals with VI.

Sports ideal for VI are: • Track and field events • Goal ball • Beep baseball • Swimming • Judo • Wrestling • Power lifting • Woman’s gymnastics • Tandem cycling • Winter sports (downhill and cross-country skiing)

Specialized equipment or modifications commonly used or related to disability

Specialized equipment can be purchased by parents and teachers at American Foundation for the Blind for catalogs of special equipment. Each year, improvements are made in sound-source balls and audible goal locators that facilitate that teaching of ball skills. Balls should be painted orange or yellow for persons with partial sight. For the most part, however, equipment does not need to be adapted for individuals with VI. The play area should be quiet enough to facilitate use of sound and well lighted to enhance use of residual vision.

Questions:

1. True or False. A severely limited field of visions is called Tunnel Vision.

2. Which of the following is not an ideal sport for children with visual impairment? A. Goal Ball B. Track and Field C. Football D. Beep Baseball 3. Which of the following classifications is the same as legal blindness? A. B1 B. B2 C. B3 4. Which of the following causes visual impairment? A. Glaucoma B. Retina C. Cataracts D. All of the above