Patients often ask the question what is legally blind and how does it affect one’s life? The definition of legally blind is when visual acuity is 20/200 or less in the better seeing eye with corrective glasses or contacts. In other words, even if one wears the best prescription glasses or contacts, he/she cannot see any better than 20/200. Normal vision is 20/20. That means a person can see a clearly what a normal person can see at that distance. 20/200 means one must stand at 20 feet to see an object where a person with normal vision can see at 200 feet. If visual impairment limits a person to 20/200 that cannot be corrected with glasses or contacts, then they are considered legally blind.
These visual impairments can be caused from a variety of reasons such as inherited diseases and birth defects, or acquired diseases such as diabetes, glaucoma, macular degeneration or even from eye injuries like blunt trauma.
People who are legally blind function quite well, but may be limited to certain activities such as driving. However, low vision devices are available to help them see such as magnifying glass for reading and telescope for seeing distance.
It is important to have your eyes checked yearly so acquired abnormalities can be detected in the early stage and greatly decrease your chances of becoming legally blind.