When asked about his vision, a patient says that the last time he had it tested, his vision was recorded as 20/50. What does this mean?

A. He can read at 20 feet what a person with normal vision can read at 50 feet.
B. He can read at 50 feet what a person with normal vision can read at 20 feet.
C. He needs to be 50 feet from objects to see them.
D. He can see objects the best between 20 and 50 feet.

A patient's 20/50 vision measurement means they can read at 20 feet what a person with normal vision can read at 50 feet, indicating a visual impairment that may require corrective lenses. So, the correct answer is option a. He can read at 20 feet and a person with normal vision can read at 50 feet.

Explanation:

When a patient says their vision was recorded as 20/50, it means he can read at 20 feet which a person with normal vision can read at 50 feet. This measurement uses the Snellen chart to determine visual acuity, which is a comparison of the patient's vision to the accepted norm of what is considered normal vision. If a person has 20/20 vision, they can see at 20 feet what most people can see at the same distance. Therefore, having 20/50 vision indicates a visual impairment, where what the individual can see clearly at 20 feet, a person with normal vision can see at 50 feet.

Visual acuity tests like these are important for determining the need for corrective lenses or other treatments to improve vision. Visual impairment can affect a wide range of activities of daily living, making such diagnostics crucial for maintaining quality of life by aiding in the correction of vision where possible.