The concept of sensorial disability embraces persons with sensory, visually , and hearing impaired; and they are so important for humans, because those are the receptors that perceive information about the world around us.
The concept of visual impairment refers to both, the blindness and other conditions of vision that do not reach it. According to the timing of deficiency, we can find blindness and visual impairment from birth and acquired, early or late; having great importance, when all this happens; because it would depend all the visual experiences, that may have been acquired before the injury.
Within this category, we found visual impairment and hearing impairment.
Visual impairment is the lack, deficiency, or decreased vision. For many people the word blind means total lack of vision, visual impairment but is divided into total blindness or amaurosis, blindness.
Partial blindness, when the vision of the person is low or there is insufficient capacity and need to wear glasses to improve it.
Macular degeneration: loss of peripheral vision and central vision is weak or a black hole.
Cataracts occur when the eye’s lens becomes cloudy; it is the most common cause of low vision in old age.
Tubular or tunnel vision: it is caused by glaucoma. Damage to the optic nerve at the back of the eye leads to a gradual loss of nerve function and can cause loss of peripheral vision.
Diabetic retinopathy is a common source of low vision in middle age. Diabetes can damage blood vessels in the eye.
Blindness: means there is difficulty distinguishing between colors, especially reds and greens.
Cortical blindness is caused by brain damage in the primary visual area of the occipital lobe although the visual organs are in good condition. The vision of the person is vague to light or movement.
Uveitis is swelling and irritation of the uvea, the middle layer of the eye that provides most of the blood flow to the retina. People with uveitis may have one or more symptoms such as blurred vision, perception of flies buzzing, eye pain, eye redness and sensitivity to light.
Trachoma: is an infection caused by the bacterium Chlamydia trachomatis, which affects mostly children in rural areas of developing countries. It begins as an inflammation of the lining of the eyelids, conjunctivitis or pink eye, without treatment can heal. Symptoms may include corneal opacity, eye discharge, swollen lymph nodes just in front of the ears, swollen eyelids and eyelashes reversed.
Now a days, we have many devices to help people with visual impairment, ophthalmologic examination, this depends to determine what kind of support they need. Here we leave some examples:
Staff: used to acquire information about the road in front of the user is not detected unbalanced on hanging objects,
Guide dogs, blind people can be transported with the help of a dog which has to be trained for several weeks, is very useful if you need to walk long distances. These dogs are not pets but companions; they should not pet him or take him by the collar without the permission of the owner.
Braille: A system of touch reading and writing in which letters, words, numbers, etc. Are points that stick out of the paper. The system has 18 abbreviations, contractions calls to save space and speed up the reading or writing.
Hearing impairment or deafness.
It refers to the individual’s inability to detect or receive at least some sound frequencies which can usually be heard by members of their species, hearing loss can be classified as mild, moderate to profound.
A deaf person uses vision as the primary mode for learning and communication.
Causes of hearing loss and deafness
If one or both parents have greater risk of hearing loss the child is born deaf.
Hearing impairment is often caused by problems during pregnancy and childbirth.
Premature birth during labor conditions in which a baby does not have enough oxygen to breathe.
Rubella, syphilis or some other infections in a woman during pregnancy.
Inappropriate use of toxic drugs (a group of over 130 drugs, such as the antibiotic gentamicin) during pregnancy.
Jaundice, which can damage the auditory nerve in a newborn baby.
Other causes include infections such as meningitis, measles, mumps and chronic ear infections can lead to hearing impairment.
Wax or foreign bodies blocking the ear canal can cause hearing loss at any age. Excessive noise, including working with noisy machinery, exposure to loud music or other noises such as gunfire or explosions can damage the inner ear and weak hearing. . As people age, accumulated exposure to noise and other factors can lead to deafness or hearing loss.
Solutions to hearing impairment focus on prevention, early detection and treatment and rehabilitation.
Sensor neural hearing loss can be prevented by:
- Meningitis, immunize children against childhood diseases like measles, meningitis, rubella and mumps.
- Immunize women of childbearing age against rubella before pregnancy.
- Detection and treatment of syphilis and certain other infections in pregnant women;
- Improved prenatal and perinatal care.