Presbyopia: Symptoms, Causes and Treatment

Introduction to Presbyopia

Presbyopia is a type of vision loss that makes it more difficult to see nearby objects clearly. It occurs naturally as we get older due to reduced flexibility of the lens inside the eye. People will usually begin to see the signs of presbyopia in their 40s and from then on their close vision will gradually get worse. Presbyopia is a natural part of ageing and is not classified as an eye disease.

The condition can be diagnosed in a routine eye exam, but it is usually first spotted when you have to hold reading material at arms-length to see it clearly. Presbyopic vision is often managed with reading glasses, but if it becomes more advanced or occurs alongside other kinds of vision loss bifocal or multifocal glasses, contact lenses or surgery may become necessary.

Symptoms of Presbyopia

Because presbyopia gets worse over time, you may notice its symptoms developing gradually or only affecting you at certain times.

Blurry vision during activities like reading is perhaps the most typical symptom of presbyopia. Objects close by may be difficult to focus on and this is most noticeable when doing close work like reading and writing. You may find that you have to adjust the lighting or distance at which you read to do so comfortably.

Headaches, eye strain and fatigue are also common symptoms. These are often noticed after reading, writing or working at a computer. They occur because the eyes have to work much harder to focus than previously. This can be exacerbated by low light, small text and other difficult reading conditions.

Causes of Presbyopia

Presbyopia is caused by natural changes that take place in the anatomy of the eye as we get older.

Part of the way the eye processes light is through a lens behind the iris, which focuses light onto the retina. In young people, the lens is flexible and able to change shape to focus on objects at different distances. As we get older, the lens gradually becomes harder and less flexible. One effect of this change in the anatomy of the eye is difficulty in focusing on objects nearby which we call presbyopia.

Presbyopia is not an eye disease, but a condition associated with ageing. This means it cannot be cured or prevented and treatment for presbyopia is aimed at improving vision and minimising its other symptoms.

Diagnosis of Presbyopia

If you notice the symptoms of presbyopia, you should book a comprehensive eye exam with your optometrist.

During the eye exam, your optometrist will ask you some questions about your symptoms, health status and family history of eye conditions. With this information combined with visual acuity and refraction tests, they will be able to tell whether you have presbyopia and whether it is accompanied by another type of vision loss or eye condition.

A visual acuity test measures how well you can see at different distances. People with presbyopia will usually have poor near vision. A refraction test looks at how well the eye refracts light towards the retina and can calculate your prescription for contact lenses and glasses. The optometrist will also examine your eye health using other tests, often including a slit lamp examination, which is a type of microscope that can look closely at different parts of the eye.

With the results of these tests and the evaluation of your symptoms, your optometrist will be able to tell whether you have presbyopia and whether any other eye conditions are present. They may then recommend glasses or contact lenses, and provide additional information about surgical options.

Treatment Options for Presbyopia

If you have presbyopia, there are many different ways to improve your vision. The best option will depend on whether you have any other problems with your vision or eye health, how advanced your presbyopia is and your personal preferences.

With a variety of glasses, contact lenses and surgical options to choose from, it’s important to get personalised advice from an optometrist who knows your case.

Glasses for Presbyopia

Glasses are a simple and affordable way to correct presbyopia. For many people, over-the-counter reading glasses, which do not require a prescription, are sufficient. There are different strength options available, so you may need advice from your optometrist on the best option for you.

If you have multiple vision problems, bifocal, or trifocal glasses will likely be prescribed. These glasses are divided into multiple sections to provide vision correction for different distances. Multifocal progressive glasses can also cover different distances and rather than using two or three distinct sections, they create smooth transitions between corrections, so you can easily change focus between objects at near, far and middle distances.

Glasses for presbyopia are an effective treatment option that can provide clear vision and different distances. As well as being affordable, glasses are non-invasive, safe and provide you with the flexibility to use them as you prefer. The main downside of glasses compared to other options is that they can limit certain activities and some people prefer the way they look without them.

Contact lenses for Presbyopia

Contact lenses are another effective option for people who prefer not to wear glasses. For most, they are safe and easy to use and also come in bifocal, trifocal and multifocal options. Similarly to glasses, bifocal contact lenses have two distinct zones for near and far vision, while multifocal lenses utilise several different zones in the lens so your eyes can smoothly transition between focusing on different distances.

Another option is monovision contact lenses, in which a lens in one eye corrects for near vision, while the other corrects for far vision. A variety called modified monovision is also available in which one lens corrects near vision and the other is multifocal. Monotype lenses sometimes take a while to get used to as the eyes adjust to the two different corrections.

Contact lenses are applied directly to the eye and some people find that this allows them to have a wider field of vision that feels more natural. They also do not change your appearance and in most cases do not limit your ability to play sports or participate in other physical activities. They do, however, require more upkeep and can take a while to get used to. Because they are in contact with the eye's surface they can also lead to side effects like dry or uncomfortable eyes.

Surgery for Presbyopia

Surgical options are aimed at eliminating or reducing the need for glasses and contact lenses. Refractive surgery is the most common option for people hoping to correct presbyopia — this works by reshaping the cornea to correct the way the eye bends light improving near or far vision. Refractive surgery for presbyopia often aims at creating the same type of vision provided with monovision contact lenses, by improving the near vision in one eye and far vision in the other.

There are various types of refractive surgery including LASIK, LASEK and PRK. These all work by using lasers to reshape the cornea, but there are slight differences in the way they work. LASIK, for example, creates a small flap in the cornea using one laser and another is used to reshape it. LASEK and PRK, on the other hand, remove a thin layer of tissue on the cornea before reshaping it and allowing it to heal.

Surgical options always carry more risks than contact lenses and glasses, but they are successful the majority of the time with most people reporting lasting improved vision. There are minor side effects associated with these surgeries but serious complications are rare. The main benefit of surgery is that it can provide potentially permanently corrected vision, allowing the patient to stop using glasses or contact lenses. It is always a good idea to discuss the different options in detail with your optometrist to ensure you understand the advantages and risks of each one.

Prevention of Presbyopia

Presbyopia is not an eye disease, but a natural part of ageing and this means that the condition itself cannot be prevented. That said, there are many ways to improve eye health and minimise your risk of other eye conditions that may make presbyopia more difficult to correct.

Regular comprehensive eye exams (at least every two years for adults) are an essential part of eye care. Catching eye conditions early on can make them much easier to manage or treat. With presbyopia, correcting it quickly with glasses or contact lenses can help to minimise associated symptoms like eye strain, headaches and fatigue.

Reading in good light, with enlarged text at a good distance for your eyes can also help to reduce the symptoms of presbyopia. These practices, as well as taking regular breaks from close work activities, can help to limit the amount of work your eyes have to do. Limiting eye strain will often help to reduce other symptoms like headaches and fatigue.

Considering your general health is also an important part of looking after your eyes. Diet and exercise have been shown to have a significant effect on how well your eyesight performs over time. Smoking is also a significant factor in eye health and has been linked to eye conditions like macular degeneration and cataracts (Boyd, 2022).

Conclusion

Presbyopia is a condition that will affect almost everyone to some degree. As we get older, learning to manage the effects of presbyopia and maintaining good eye health can help us to protect our quality of life. From attending regular eye exams to eating healthily, there are plenty of ways you can look after your eyes.

While presbyopia may be a frustrating condition, there are many effective treatment options available. The best way to treat presbyopia will depend on your eyes and your lifestyle. Whether you want to focus on maintaining an active lifestyle or need to manage more than one eye condition, it is important to work with your optometrist to find a treatment plan that works for you.

References

Boyd, K. (2022). Smoking and Eye Disease.  American Academy of Ophthalmology. https://www.aao.org/eye-health/tips-prevention/smokers