Visual acuity describes the sharpness and clarity of vision. Eye care professionals commonly measure it using a Snellen eye chart, which presents rows of letters that decrease in size to determine how well a person can see details from a specific distance.
What 20/70 Vision Means
20/70 vision refers to a specific measurement on the Snellen eye chart. The first number, 20, indicates the distance in feet at which the test is conducted, typically 20 feet from the chart. The second number, 70, signifies that a person with 20/70 vision can discern at 20 feet what a person with normal vision (20/20) can see clearly from 70 feet away. Objects appear less distinct for someone with 20/70 vision compared to 20/20 vision.
A visual acuity of 20/70 is considered a moderate visual impairment or moderate low vision by the World Health Organization. It represents a noticeable reduction in visual sharpness, meaning details at a distance are significantly blurred. While 20/70 vision is below average, it is not classified as legal blindness, which is typically defined as 20/200 or worse in the better eye with the best possible correction.
Daily Life with 20/70 Vision
Living with 20/70 vision can introduce various challenges in everyday activities that rely on clear distant sight. Reading street signs or identifying bus numbers from a distance often becomes difficult. Recognizing faces of friends or acquaintances until they are quite close may also pose a challenge. These situations can impact navigation and social interactions in public spaces.
Driving often presents significant limitations for individuals with 20/70 vision. Many jurisdictions impose restrictions, such as requiring corrective lenses or limiting driving to daylight hours. Activities like sports that demand precise visual tracking, such as hitting a baseball, can also be more difficult. Hobbies requiring fine distant detail, like birdwatching, may similarly become challenging without appropriate visual aids.
Addressing and Improving 20/70 Vision
20/70 vision can be effectively managed and improved with standard corrective measures. Prescription eyeglasses and contact lenses are the most common solutions, designed to properly focus light onto the retina and enhance visual clarity. An eye care professional determines the precise lens power needed through a comprehensive eye examination.
Refractive surgeries, such as LASIK, offer another potential avenue for vision improvement for some candidates. These procedures reshape the cornea to correct refractive errors, aiming to reduce or eliminate the need for glasses or contact lenses. However, suitability for such surgeries depends on various factors, including the underlying cause of the vision impairment and overall eye health.
If 20/70 vision persists even with the best conventional corrective lenses, it may be categorized as “low vision,” which cannot be fully corrected by standard means. Specialized low vision aids, like magnifiers or telescopes, can help maximize remaining sight and assist with daily tasks.
When to Consult an Eye Doctor
Regular eye examinations are important for maintaining eye health and detecting potential vision issues early. An eye care professional can assess visual acuity and identify any changes that may indicate a need for corrective lenses or further intervention.
It is important to consult an eye doctor if experiencing sudden changes in vision, such as new blurriness or difficulty seeing. Other concerning symptoms that warrant immediate professional attention include eye pain, flashes of light, or an increase in floaters. Persistent headaches or eye fatigue may also signal uncorrected vision problems that require evaluation.