The normal visual acuity of human eyes is generally above 1.0, and 0.3 is considered by the ophthalmology community as the low limit to ensure that people can live comfortably. If the best vision of both eyes is less than 0.3 even after surgery, medication and correction of ordinary glasses, the quality of life will be seriously affected and there will be difficulties in seeing far (e.g. watching TV, reading street signs) or near (e.g. reading newspapers, writing). For this reason, the World Health Organization defines the best corrected visual acuity of both eyes as being within the range of 0.3 to light perception or a visual field radius of less than 10. Low vision is defined as low vision.
Low vision is a state of low visual function, not a specific eye disease, and any eye disease can lead to impaired vision that cannot be restored. Low vision seriously affects the patient’s ability to live and work independently on a daily basis, causing great inconvenience to themselves and their families. Therefore, many people with low vision are worried that their eyes are “blind” and useless.
However, experience has shown us that most people with low vision can or may be able to use their residual vision to organize or perform a job if they are supported by appropriate low vision rehabilitation efforts. Low vision and blindness are two very different concepts. Blindness means that the eye cannot even perceive light, i.e., there is no sense of light.
Rehabilitation measures for patients with low vision include: (1) Treatment of the original disease.
(2) Fitting of visual aids.
(3) Training in the use of visual aids.
(4) Training of functional vision.
(5) Psychological rehabilitation and social support The current low vision rehabilitation we can perform includes detailed eye examination, visual function assessment, fitting of various types of visual aids, and appropriate visual function training, and providing advice and guidance on certain living or working environments to ensure maximum mobility and participation in life and work.
A visual aid is any device or equipment that improves or enhances the vision and mobility of a person with low vision. The use of appropriate visual aids is the primary means of low vision rehabilitation, and approximately 50-70% of people with low vision can rely on visual aids to improve their vision.
Types of visual aids include: (a) optical visual aids: including distant and near visual aids. The distant ones such as binoculars (optional for elderly people watching TV), monocular binoculars (for students reading the blackboard in class or looking for stop signs and road signs), etc.; the near ones such as various types of hand-held mirrors, spectacle-type vision aids, binoculars for both near and far, etc.
(B) other visual aids: including glare glasses and non-visual aids such as laser canes, guide dogs.