Interpreting Your Eye Prescription: A Guide to Deciphering the Numerical Values
More than one-third of Americans experience presbyopia, a condition that develops as the aging eye lens becomes less flexible and stiffer, according to recent studies. As people age, it's crucial to pay special attention to the health of their eyes, particularly those with diabetes, high blood pressure, or a family history of eye problems, as advised by the American Academy of Ophthalmology.
Regular, thorough eye exams are essential for maintaining and improving vision. A complete eye exam should involve dilating the pupils, reviewing medical history, testing pupil health, performing a visual acuity test, a peripheral vision test, an eye pressure check, a retina and optic nerve review, an eye movement test, an eye alignment and eye muscle health test, a lens, cornea, iris, and eyelid check.
Age-related macular degeneration is the leading cause of blindness in people over 65, according to the National Institutes of Health (NIH). Glaucoma, if left untreated, can cause vision loss and blindness. Anyone who notices changes in their vision should speak to a medical professional to ensure early diagnosis and treatment.
Each component of an eye prescription corresponds to a specific aspect of vision correction and affects vision based on the type of refractive error or eye condition it addresses. The spherical correction (SPH) indicates the degree of nearsightedness or farsightedness. A negative value (e.g., -2.00) corrects nearsightedness (myopia), while a positive value (e.g., +2.00) corrects farsightedness (hyperopia).
Cylindrical correction (CYL) represents the amount of astigmatism, which is an irregular curvature of the cornea or lens causing blurred or distorted vision. The cylinder value indicates the lens power needed to correct the uneven focus. A higher absolute CYL value means more astigmatism correction is required. The axis notation tells lens makers where they should place the astigmatism correction in a lens.
The ADD number is used for multifocal lenses and represents additional magnifying power for reading or close work, typically for presbyopia (age-related loss of near vision). Prism is incorporated into a lens to help correct problems with the eyes working together.
It's important to note that eyeglass prescriptions change due to natural changes in people's eyes, not usually due to illness. Positive numbers in an eye prescription (+1.00) indicate the strength of a lens needed to correct farsightedness. A +0.25 eye prescription indicates a person has mild farsightedness (American Academy of Ophthalmology guide). A -6.5 prescription indicates significant shortsightedness, meaning distant objects are very blurry (American Academy of Ophthalmology guide).
Children's eyes continue to change rapidly as they grow, and they should see an eye doctor each year. The axis notation tells lens makers where they should place the astigmatism correction in a lens. OS on an eyeglasses prescription refers to the left eye (Oculus Sinister), while OD refers to the right eye (Oculus Dexter). A 1.75 prescription, whether -1.75 (shortsightedness) or +1.75 (farsightedness), indicates moderate vision impairment (American Academy of Ophthalmology guide).
People who have a high risk of vision loss in the United States only half have seen an eye doctor in the past year (CDC). Cataracts are expected to develop in over 50% of people in America by age 75, according to the National Institutes of Health (NIH). Diabetes and high blood pressure can cause damage to the retina and vision loss, although no specific source was mentioned.
Understanding these components helps you grasp how your glasses or contacts improve your vision clarity and comfort. Anyone experiencing changes in their vision or concerns about their eye health is encouraged to speak to a medical professional for guidance and care.
- As specified by the American Academy of Ophthalmology, regular, thorough eye exams are vital for those with diabetes, high blood pressure, or a family history of eye problems, as they involve dilating the pupils, testing eye pressure, and reviewing medical history.
- A complete eye exam can also include tests for peripheral vision, eye movement, eye alignment, and muscle health, as well as checks for the health of the lens, cornea, iris, and eyelid.
- A high CYL value, representing astigmatism, indicates a greater need for astigmatism correction, while the axis notation tells lens makers where to place the astigmatism correction in a lens.
- Changes in a person's vision should prompt them to consult a medical professional, as this could be an early sign of conditions like age-related macular degeneration or glaucoma, which can cause blindness if left untreated.
- Presbyopia, a common age-related condition, can be addressed with a special ADD number in multifocal lenses, providing additional magnifying power for reading or close work.
- Prism is used in lenses to correct problems with the eyes working together, whereas each component of an eye prescription changes due to natural changes in people's eyes, not usually due to illness.
- People with a higher risk of vision loss in the United States only account for half of those who have seen an eye doctor in the past year, according to the CDC.
- Specific medical conditions like diabetes and high blood pressure can cause damage to the retina and potential vision loss, as outlined in science and medical literature. In addition to these diseases, mental health conditions such as depression and bipolar disorder, psoriatic arthritis, HIV, and general aging may also have an impact on eye health, making it essential for individuals to prioritize health-and-wellness, mental-health, and regular eye examinations as they grow older.
