Monofocal Vs. Multifocal Lenses – A Cataract Expert Explains the Difference

Medically reviewed on 21-September-2023

When you’re being considered for cataract surgery, you’ll need to think about the type of intraocular lens implant (IOLs) that might be best suited for you.

There are a number of different options that you can choose from, and in this post, we’ll explore the main differences between cataract monofocal vs multifocal lenses.

Before deciding on the type of lens that may work best, you’ll need to consider your daily activities since the different IOL types provide a variety of different benefits. So, your choices could vary depending on whether you’re an active outdoor enthusiast, a driver, an avid reader, a busy professional, or a combination of these.

As each type of intraocular lens has its own offerings, and as choices also differ depending on the type of refractive condition you have, such as far- or near-sightedness or astigmatism , we’ve created this short guide to help you make an informed choice.

What is the Difference Between Monofocal and Multifocal Lenses?

While monofocal lenses provide focus at one distance only, multifocal lenses allow for vision at a range of distances, meaning they can correct both near, intermediate, and far distances. These are a more popular option for those who want to also eliminate their dependency on glasses.

Monofocal Lenses

Monofocal lenses have a fixed focal point, meaning they are set to provide clear vision at a specific distance, either for near, intermediate, or distance vision. Monofocal IOLs have a single focus point and cannot adjust or accommodate different distances.

Advantages of Monofocal Lenses

Monofocal lenses, when used in cataract surgery, offer several advantages that make them a popular choice for many patients. These advantages include:

1. Excellent Distance Vision. Monofocal lenses are designed to provide exceptional clarity and sharpness for distance vision. Patients with monofocal lenses set for distance typically experience improved vision for activities such as driving, watching TV, or recognising faces at a distance.
2. Proven and Predictable Results. Monofocal IOLs have been used for many years in cataract surgery, and their outcomes are well-established. Surgeons can predict and customise the desired focal point with a high degree of accuracy, leading to reliable results.
3. Cost-Effective. Monofocal IOLs are often more budget-friendly compared to premium lens options, such as multifocal IOLs. This can be appealing to patients concerned about the cost of cataract surgery.
4. Reduced Need for Glasses (for One Distance) Patients who receive monofocal lenses set for distance vision can experience a reduced need for glasses for activities like driving. While they may still require reading glasses or bifocals for close-up tasks, the overall dependence on glasses can be lessened and if a prescription is required it is usually lighter
5. No  Maintenance. Monofocal IOLs do not require any adjustments or maintenance by the patient. Once they are implanted, they work passively to provide clear vision at their designated focal point.

Better Vision in Low Light. If you still require glasses after your surgery, you may find that you have better vision in low light than you would have had if you had chosen multifocal lenses.

Disadvantages of Monofocal Lenses

While monofocal lenses offer several advantages, they also come with certain disadvantages. It’s important for patients to be aware of these limitations when considering monofocal lenses:

1. Limited Range of Focus. Monofocal lenses have a fixed focal point, which means they are set to provide clear vision at either near, intermediate, or distance, but not all three simultaneously. Patients with monofocal lenses for distance vision will still require reading glasses for near tasks, and those with monofocal lenses for near vision will need glasses for distance vision.
2. Dependence on Glasses. Regardless of the choice (distance or near vision), patients with monofocal lenses typically require glasses for activities outside the designated focal point and in some cases for all focal points. This can include reading, computer work, and intermediate tasks.
3. Limited Depth Perception (with Monovision) In cases of monovision, where one eye is set for near vision and the other for distance, some patients who are not adapted to this set-up may experience reduced depth perception or visual comfort. This can affect activities that require precise depth perception, such as sports or certain job tasks.
4. Multifocal Distraction. In situations where patients receive monofocal lenses for distance vision but desire clear near vision, the use of reading glasses can sometimes be distracting or inconvenient.
5. Prescription Changes. Over time, patients may experience changes in their eyeglass prescription, which could necessitate updated glasses for their uncorrected eyes.
6. No Adjustable Focus. Unlike multifocal or accommodating lenses, monofocal lenses do not adjust to different distances. Therefore, they may not meet the visual demands of individuals who require clear vision at various distances throughout the day.

Monofocal Lenses for Monovision

A vision improvement technique using monofocal lenses, monovision gives you the option to implant different lenses in each eye during cataract surgery so that you can see at two different distances, typically near and distance.

In monovision, one eye is implanted with a monofocal lens set for near vision, while the other eye receives a monofocal lens set for distance vision. This approach allows the brain to adapt to having one eye optimised for tasks like reading and close-up work (near vision) and the other eye optimised for activities like driving or seeing objects at a distance (distance vision).

Advantages of Monofocal Lenses

Monofocal lenses used in a monovision approach offer several advantages for individuals, such as:

Monofocal lenses used in a monovision approach offer several advantages for individuals who require clear vision at two different distances (near and distance vision). These advantages include:

1. Reduced Dependence on Glasses. Monovision with monofocal lenses allows individuals to reduce their reliance on glasses for everyday activities. One eye is optimised for near tasks like reading, while the other eye is optimised for distance vision, minimising the need for reading glasses or bifocals.
2. Improved Convenience. Individuals can switch between near and distance tasks more easily. This is particularly advantageous for tasks like driving, reading, using a computer, and seeing objects at a distance without the need to constantly put on and remove reading glasses.
3. Enhanced Flexibility. You’ll enjoy flexibility in daily activities, allowing for comfortable and functional vision at both near and far distances. This adaptability can improve the overall quality of life for individuals who require clear vision in different scenarios.
4. Well-Established Technique. Monovision with monofocal lenses has been used successfully for many years in cataract surgery and refractive lens exchange. Its safety and efficacy are well established, making it a reliable choice for certain patients.
5. Customizable to Individual Needs. Monovision can be tailored to each individual’s specific visual requirements and preferences. The degree of monovision can be adjusted to maximise comfort and visual performance.
6. Preservation of Functional Vision. While monovision may not provide perfect vision at all distances simultaneously, it aims to preserve functional vision for daily activities, which can significantly improve a person’s overall quality of life.

Disadvantages of Monovision

The compromises that patients may need to accommodate when opting for monovision may include:

1. Reduced Depth Perception. Monovision with monofocal lenses can compromise your depth perception, as one eye is optimised for distance vision while the other is set for near vision. This can make tasks such as judging distances and catching moving objects more challenging.
2. Adaptation Period. Adjusting to monovision can take time and patience. It requires learning a new set of skills to adapt to the different vision in each eye. You will be tested for your tolerance for this if you are considering it as an option.
3. Night Vision Issues. Monovision can cause difficulties with night vision, including glare, halos, and reduced contrast sensitivity. These issues can make driving at night or navigating in low-light conditions more challenging.
4. Decreased Near Vision. Monofocal monovision typically emphasises intermediate and far vision, but it may not provide optimal near vision for tasks like reading a small print book or playing a musical instrument. You might still require reading glasses for such activities.
5. Limited Flexibility. Monofocal monovision is a fixed solution that may not suit all aspects of your lifestyle. If your visual needs change or if you want more balanced vision at all distances, additional corrective measures may be necessary.
6. Compatibility Issues. Monovision might not be suitable for those who are not adapted to monovision in contact lenses. Some individuals may not adapt well to this visual arrangement, and it may not be the best choice for those with certain eye conditions or professions that demand precise vision. Tests will be carried out to check if you are a suitable candidate for monovision or not.

Multifocal Lenses

This type of lens will allow you to see all ranges of vision: near, intermediate, and far. The lenses work by using several different optical powers at varying points across the lens. These work best if they are implanted in both eyes.

When deciding between monofocal and multifocal lenses, the patient will discuss lifestyle factors and vision goals with the consultant to arrive at a recommendation.

Advantages of Multifocal Lenses

Multifocal lenses offer enhanced visual flexibility when compared to monofocal lenses. Some key benefits include:

1. Reduced Dependence on Glasses. Correct vision at multiple distances, allowing patients to enjoy improved near, intermediate, and distance vision without relying as heavily on glasses. Activities such as reading, using a computer, or watching TV can be more comfortable without the constant need for reading glasses. In fact, 95 percent of people find that they no longer need to wear glasses for their activities once they have made the choice to have these lenses implanted.
2. Enhanced Convenience. Patients can transition seamlessly between different tasks and activities without the hassle of switching between multiple pairs of glasses. This convenience is particularly valuable for those with active lifestyles or those who engage in various activities throughout the day.
3. Improved Quality of Life. Multifocal lenses can significantly enhance the overall quality of life for cataract surgery patients. Everyday activities such as cooking, playing sports, or gardening can be more enjoyable when clear vision is available at various distances.

Disadvantages of Multifocal Lenses

As with any type of lens, multifocals also carry some potential disadvantages. These can include:

Somewhere between five and ten percent of patients who opt for this lens suffer some kind of halo or glare when looking at lights at night. However, many patients do adapt to this after a short period of time.

This type of lens can sometimes be associated with a struggle with contrast, which may have a negative impact if you are trying to read something in dim light. Of course, it is bad for your eyes if you read in dim light anyway, so this should be avoided whether you have had lens replacement surgery or not.

A small percentage of patients may need light readers when looking at fine print.

What next? Get in touch for free, expert advice.

Choosing the right lens for your lifestyle requires careful thought and consideration. If you’re looking to have cataract surgery, why not book a free, no-obligation virtual consultation with us? We can advise you on the lens and treatment type that might be most suitable for your personal lifestyle and vision goals.

By Author: Alastair Stuart

Mr. Alastair Stuart is one of a handful of surgeons worldwide who has received formal Laser Eye Surgery Training. He is a key opinion leader and Consultant for both Carl Zeiss Meditec and Rayner for whom he has given several International presentations. Mr Stuart has completed over 2000 laser eye surgeries, including more than 1000 SMILE procedures, and over 2000 cataract/lens based surgeries.