SUB-VISION / TECHNICAL AIDS
Sub-Vision is a significant decrease in visual acuity or a reduced field of vision.
The term sub-vision is used when the vision is so impaired that performing everyday tasks becomes difficult. Sub-vision may be congenital or acquired; it may be the result of pathologies in the transparent media of the eyeball (cornea, crystalline or vitreous), iris, retina and optic pathways or cerebral cortex. The main pathologies that lead to sub-vision are: Optic Nerve Atrophy, High Myopia, Congenital Cataracts, Glaucoma, Age-related Macular Degeneration, and other Retinopathies (such as Pigmentary Retinitis or Stargardt’s Disease).
It is a condition that cannot be corrected with surgery, medications, or ordinary glasses. However, those affected may benefit from sub-vision aids, which help to minimize the consequences of visual impairment, improve quality of life, and provide greater independence. There are various aids for different purposes, which can maximize the visual residue, enabling the patient to retain more active vision.
Optical aids: A wide range of lens systems ranging from simple magnifying glasses, to lighted magnifiers, telescopes (for near or far vision) or prisms.
Non-optical aids: Special filters, use of contrast, typeface and size of letters, reading and writing guides, recorders, special types of paper, markers.
Electronic aids: Information processing systems such as character magnifiers, hardware or software systems.
Ergonomic aids: The type of lamp, the lighting conditions, the location within a room, the reading table, and even posture are basic conditions for being able to perform tasks well, promoting visual efficiency.