The terms presbyopia and hypermetropia, often used interchangeably by mistake, describe two distinct conditions affecting near vision. While both can cause difficulty seeing up close, their underlying causes are fundamentally different, leading to different treatments and prognoses. Understanding these differences is crucial for anyone experiencing vision changes as they age.
What is presbyopia?
Presbyopia comes from Greek words meaning "old eye" and is a natural, inevitable part of the aging process. It typically starts to manifest in the early to mid-40s and progresses until around age 65. This condition occurs because the lens inside your eye, which is normally soft and flexible, gradually becomes harder and less elastic over time. This reduced flexibility makes it difficult for the lens to change shape and focus on close-up objects, resulting in blurry near vision.
Symptoms of presbyopia
The symptoms of presbyopia develop gradually and worsen over time. Common signs include:
- Holding reading materials farther away to make the letters clearer.
- Blurred vision at a normal reading distance.
- Eyestrain, headaches, or fatigue after doing close-up tasks.
- The need for brighter lighting when reading or doing near work.
- Difficulty switching focus between near and far objects.
Causes of presbyopia
The primary cause is the natural aging process. The lens loses flexibility, and the muscle fibers surrounding it weaken, hindering the eye's ability to accommodate or focus. This means that everyone, regardless of their prior vision, will experience some degree of presbyopia with age.
What is hypermetropia (farsightedness)?
Hypermetropia, or farsightedness, is a refractive error caused by the shape of the eye, not by aging. In a person with hypermetropia, the eyeball is either shorter than normal or the cornea is too flat. This causes light rays to focus behind the retina instead of directly on it, making close-up objects appear blurry. Unlike presbyopia, hypermetropia can be present from birth and affect people of any age, including children.
Symptoms of hypermetropia
While some of the symptoms may overlap with presbyopia, hypermetropia can also present differently, especially in younger people who have not yet developed presbyopia. Symptoms can include:
- Difficulty seeing objects up close.
- Eye strain, particularly after reading.
- Headaches from focusing on near tasks.
- For children, undiagnosed hypermetropia can sometimes lead to strabismus (crossed eyes).
Causes of hypermetropia
Hypermetropia is caused by a physical abnormality in the eye's structure. The two main causes are:
- Short eyeball length: The distance from the front to the back of the eye is too short.
- Flat cornea: The cornea's curvature is too flat, so it doesn't bend light enough.
How can presbyopia and hypermetropia coexist?
It is entirely possible for a person to have both hypermetropia and presbyopia simultaneously. In fact, it is quite common. A person who has been farsighted (hyperopic) their entire life will eventually also develop presbyopia after age 40. For these individuals, the combination of a structurally-based focusing problem and an age-related loss of focusing power makes near vision even more challenging. In such cases, corrective lenses, such as bifocals, trifocals, or progressive lenses, are necessary to correct vision at multiple distances.
Comparison of presbyopia vs. hypermetropia
| Feature | Presbyopia | Hypermetropia (Farsightedness) |
|---|---|---|
| Cause | Loss of flexibility and hardening of the eye's natural lens due to aging. | Shorter-than-normal eyeball or a cornea that is too flat. |
| Age of Onset | Typically begins around age 40 and affects almost everyone. | Can be present from birth and affect people of any age. |
| Progression | Worsens gradually over time, stabilizing around age 65. | Can be stable or worsen slowly; not tied to the same aging process. |
| Symptom Basis | Inability of the lens to adjust focus for near objects. | Light focuses behind the retina due to eye shape. |
| Treatment | Reading glasses, bifocals, multifocal contacts, or lens replacement surgery. | Prescription glasses, contacts, or refractive surgery (like LASIK) that reshapes the cornea. |
Conclusion
In conclusion, the answer to is presbyopia called old age hypermetropia is no. While presbyopia is sometimes inaccurately described as "old age farsightedness" due to the similarity in symptoms, the two are distinct vision problems with different causes. Presbyopia is an age-related condition resulting from a natural hardening of the eye's lens, affecting nearly everyone. Hypermetropia, on the other hand, is a refractive error caused by an irregular eye shape and can affect individuals at any age. It is possible to experience both conditions simultaneously, and an eye care professional can provide an accurate diagnosis and appropriate treatment options, which range from corrective eyewear to surgical procedures.
How an eye doctor can help
Regular, comprehensive eye exams are the best way to distinguish between these conditions and determine the most effective treatment plan. An optometrist or ophthalmologist can perform a refraction assessment to measure your focusing ability and provide a precise diagnosis. For presbyopia, options may include over-the-counter reading glasses for mild cases or prescription bifocals and progressive lenses for more complex needs. Those with hypermetropia might receive a specific prescription for corrective lenses or be candidates for laser surgery that reshapes the cornea.
