Presbyopia (Age-Related Farsightedness)

Presbyopia, also known as age-related farsightedness or longsightedness, refers to the ageing process of the eye's lens that develops with increasing age. It is characterised by a gradual loss of the ability to see objects up close clearly. For example, it may manifest as the need for reading glasses.

What is Presbyopia?

Presbyopia refers to the gradual loss of the ability to see objects up close as we age. Unlike nearsightedness, farsightedness, or astigmatism, presbyopia is not a refractive error or a disease, but a normal ageing process. It can be corrected with visual aids or surgery.

How Does Presbyopia Manifest?

Presbyopia affects everyone eventually, even if you've never needed glasses before. It usually begins between the ages of 40 and 45. The symptoms of presbyopia develop gradually. Often, people first notice a decline in near vision when they have difficulty reading small print.

If you notice that you're having trouble reading small print, whether in printed form or on the screens of phones, tablets, computers, etc., you might be experiencing the onset of presbyopia.

Symptoms of presbyopia include:

• Difficulty seeing things clearly up close or trouble focusing vision.
• Needing to hold text further away from the eyes to read it.
• Eyes feeling tired, strained, or irritated.
• Headaches and general fatigue.

Optometrists or ophthalmologists can diagnose presbyopia with a near-vision test and determine the necessary correction. This includes measuring the diopter values. The refractive error can then be corrected with an appropriate visual aid, such as reading or bifocal glasses.

What is the Cause of Presbyopia?

Over time, the eye's lens gradually loses the ability to focus on near objects because it loses its elasticity as we age. Additionally, the eye muscle that controls the movements and contraction of the lens weakens with age.

The lens is located inside the eye, behind the iris. It changes shape to focus light on the retina, allowing objects at different distances to be seen clearly.

In younger years, the lens is soft and flexible, making it easy to change shape. This allows both near and far objects to be focused on (known as accommodation). After the age of 40, the lens loses its elasticity and cannot change its shape as easily. The strength of the eye muscle that controls the curvature of the lens also decreases over time.

The result: The eye can no longer focus sharply on certain areas and you’ll notice your vision getting worse. This makes tasks like reading, threading a needle, or other close-up activities more difficult.

How Can Presbyopia Be Treated?

There is no way to stop or reverse the normal ageing process that causes presbyopia. However, presbyopia treatment can include the use of glasses, contact lenses, or a refractive lens exchange, where the eye's natural lens is replaced with an artificial one.

Glasses for Presbyopia

Glasses can be used to correct presbyopia. Here is an overview of when different types of lenses are used:

• Reading Glasses: If correction is only needed for reading, a simple pair of reading glasses is sufficient.
• Progressive Lenses: If in addition to presbyopia, conditions like nearsightedness are present, you would need to change glasses to see both near and far clearly. Progressive lenses (also called "varifocal lenses" or colloquially "Varilux lenses") cover all distances from near to far, taking into account existing distance corrections (myopia, hyperopia, and astigmatism), so only one pair of glasses is needed.
• Bifocal and Trifocal Glasses: A bifocal lens consists of two halves with different diopter values, while trifocal lenses are divided into three sections. One section is for near vision, and the others are for distance vision. Unlike progressive lenses, there is no gradual transition between the different strengths, making the use of multifocal glasses less comfortable for most people.

Contact Lenses for Presbyopia

Contact lenses are also available for presbyopia. There are different options for this:

• Multifocal Contact Lenses: If in addition to presbyopia, nearsightedness or farsightedness is present, multifocal contact lenses may be suitable. These lenses are divided into different areas with varying powers, allowing for clear vision at all distances.
• Bifocal Contact Lenses: Unlike multifocal lenses, bifocal lenses consist of only two areas: one for distance vision and one for near vision. When looking straight ahead, you see clearly at a distance, and when you look down, you see clearly at close range.
• Single-Vision Contact Lenses: Single-vision lenses can also be used to correct presbyopia. In a technique called "monovision," one eye is fitted with a lens for near vision, and the other is for distance vision. This requires some adjustment time as the brain needs to learn to use one eye for each specific distance. Unfortunately, this method can make it difficult to judge distances and speeds, which is why monovision is not suitable for driving.

Can Presbyopia Be Treated Permanently?

Yes, presbyopia can be permanently corrected with a refractive lens exchange (RLE). In this procedure, the eye's natural lens is replaced with a multifocal artificial lens, allowing the eye to focus clearly at both near and far distances. Usually, no adjustment period is needed. With advancing age, laser treatment is generally not recommended: the correction achieved is more likely to be temporary, as the lens's loss of elasticity progresses further with age. Additionally, older age itself is a significant risk factor.

FAQ: Frequently Asked Questions about Presbyopia

Can presbyopia be prevented?

Unfortunately, it is not possible to prevent or avoid presbyopia. It is a natural part of the ageing process and eventually affects everyone as the eye's lens loses elasticity and the eye muscle loses strength. It is therefore completely normal for vision to decline with age.

When does presbyopia begin?

Most people develop presbyopia by the age of 60. However, it usually starts between the ages of 45 and 50. Presbyopia typically progresses and then stabilises. After around the age of 65, it usually stabilises and does not progress any further.

How quickly does presbyopia progress?

The progression of presbyopia varies individually. It often begins with the need to hold small print farther away to read it. Over time, this no longer suffices, and vision aids are required.

Does everyone become presbyopic?

Presbyopia eventually affects everyone. It is not a pathological change in the eye but a part of the natural ageing process. The only variation is the age at which it appears and the degree of presbyopia.

Do nearsighted people also become presbyopic?

Presbyopia can occur regardless of nearsightedness. Being nearsighted does not "protect" against presbyopia. As the lens loses its elasticity with age, presbyopia develops. If someone has nearsightedness in addition to presbyopia, the eye may not see clearly at either near or far distances, and both refractive errors may need correction.

What is the difference between farsightedness and presbyopia?

In normal farsightedness (hyperopia), the focal point is formed behind the retina, making nearby objects appear blurry. This is often due to a too-short eyeball or insufficient refractive power of the lens. Presbyopia, on the other hand, results from the age-related loss of lens elasticity, even if someone has never had farsightedness throughout their life.

Is there also age-related nearsightedness?

Normal nearsightedness (myopia) usually develops in young people, typically before the age of 25, and can worsen until about age 30. Sometimes, nearsightedness may only appear after the age of 40, which is called age-related nearsightedness. Like presbyopia, the cause is the loss of elasticity in the lens.