Scleral lenses are often prescribed to provide clear, stable vision for people with keratoconus, irregular corneas, corneal grafts and other complex corneal conditions.
But what happens when your distance vision is excellent and you start needing reading glasses over the top?
For many patients, particularly from their 40s onward, the problem is no longer just correcting the irregular cornea. They also need help focusing on phones, computers, menus and other near tasks.
In selected patients, a scleral lens can be designed with multifocal optics, allowing the same lens to provide useful distance, intermediate and near vision.
Importantly, multifocal scleral lenses do not have to use the same fixed optical design for everyone.
At Westmead Eyes, we can customise the multifocal optics according to the way the lens sits on the eye, the patient’s pupil and their individual visual requirements. Please book an appointment with Kevin Trac for this service.
Why Do Scleral Lens Wearers Start Needing Reading Glasses?
As we get older, the natural lens inside the eye gradually loses its ability to change focus from distance to near.
This is called presbyopia.
It happens regardless of whether you have keratoconus or wear scleral lenses.
A patient may therefore have an excellent scleral lens that corrects their distance vision beautifully but eventually find themselves holding their phone further away or reaching for reading glasses.
For some patients, wearing reading glasses over their scleral lenses is perfectly acceptable.
Others would prefer to reduce their dependence on readers, particularly if they frequently alternate between distance, computer and near tasks throughout the day.
That is where a multifocal scleral lens may be worth considering.
How Does a Multifocal Scleral Lens Work?
Rather than having one optical power across the entire lens, a multifocal scleral lens contains different optical zones designed to provide vision at more than one distance.
A lens may incorporate areas intended predominantly for:
distance, intermediate and near vision.
Your brain learns to use the most useful visual information depending on what you are looking at.
This is sometimes called simultaneous vision.
The important point is that multifocal scleral optics can often be customised considerably more than patients realise.
Why Isn’t There One Standard Multifocal Design?
Because people’s visual demands are very different.
Consider two patients of the same age.
One drives extensively at night and only occasionally reads on a phone.
Another spends eight hours a day working at a computer and needs comfortable intermediate and near vision much more frequently.
Giving both patients exactly the same multifocal design may not produce the best result.
Depending on the lens design being used, we can alter parameters such as the size and distribution of the optical zones to place greater emphasis on the distances that matter most to that patient.
What Can Be Customised?
With a customised multifocal scleral design, factors we may consider include:
- the size of the central optical zone
- whether the design is predominantly centre-distance or another configuration
- the amount of near addition
- how the power changes from distance through intermediate to near
- pupil size
- the position of the lens relative to the pupil
- how stable the lens is on the eye
- how much distance versus near emphasis each eye receives
- the patient’s actual work, reading and driving requirements
The two eyes do not necessarily need to have identical multifocal optics.
For example, one eye may be designed to retain slightly stronger distance emphasis while the other contributes more to intermediate or near vision.
The objective is to find the best binocular balance, rather than simply putting the same multifocal pattern in both lenses.
Why Does Lens Centration Matter?
This is particularly important with scleral lenses.
A scleral lens may sit slightly lower, higher or to one side depending on the shape of the eye underneath it.
With a conventional single-vision lens, modest decentration may have relatively little effect on vision.
With multifocal optics, however, the relationship between the optical zones and the patient’s pupil becomes much more important.
If the near and distance zones are not positioned appropriately relative to where the patient is actually looking through the lens, visual performance may be compromised.
What About Pupil Size?
Pupil size can affect how much of each optical zone contributes to the patient’s vision.
The pupil changes size depending on lighting.
It is generally smaller in bright conditions and larger in dim conditions.
This partly explains why a multifocal contact lens can behave differently during daylight compared with night driving.
When we design the optics, we therefore need to consider not only the reading prescription but also how the patient’s pupil and lens position interact with the multifocal zones.
Can Multifocal Scleral Lenses Work With Keratoconus?
Yes, in selected patients.
One of the advantages of a scleral lens is that it can first provide a relatively stable optical surface over an irregular cornea.
Once we have a comfortable and stable fit with good distance vision, we can then consider whether multifocal optics can be incorporated.
However, keratoconus can produce complex optical aberrations.
If significant ghosting, glare or higher-order aberrations remain even with a well-fitted scleral lens, these issues may need to be addressed separately when determining whether a multifocal design is appropriate.
The first priority is generally to achieve good, stable baseline vision.
Then we can consider adding the complexity of multifocal optics.
Will Multifocal Scleral Vision Be as Sharp as Single-Vision Scleral Lenses?
There can be a trade-off.
A single-vision scleral lens directs its optical design primarily toward one distance.
A multifocal lens deliberately distributes optical information across more than one distance.
Some patients achieve an excellent balance and are able to perform most daily tasks without additional glasses.
Others may notice that distance or near vision is not quite as crisp as it would be through a dedicated single-vision lens.
This is similar to other multifocal contact-lens systems.
The goal is usually not necessarily to create the absolute sharpest possible vision at one distance.
The goal is to create useful vision across the range of distances the patient actually needs during the day.
Do I Have to Give Up Night Driving Vision?
Not necessarily.
If distance vision (particularly night driving) is a major priority, the multifocal design can be biased accordingly.
For example, we may choose to preserve stronger distance emphasis while providing enough intermediate and near assistance to reduce dependence on reading glasses.
This is where customisation becomes valuable.
A person who drives extensively may need a very different optical balance from someone primarily working at a computer.
What If I Mainly Need Computer Vision?
This is another reason not to think of multifocal lenses purely as “distance and reading”.
For many patients, intermediate vision is actually the most important working distance.
Desktop monitors, laptops, vehicle dashboards and many workplace tasks fall between traditional distance and reading vision.
The optical design can therefore be considered around the patient’s real working distances rather than simply asking:
“What reading add do you need?”
Can My Existing Scleral Lenses Be Upgraded to Multifocal?
Potentially, yes.
This is an important option for existing Westmead Eyes scleral-lens patients.
If your current lenses are comfortable, stable and already providing good distance vision, we may not need to start the entire fitting process again.
Your successful existing fit can often provide a very useful starting point for designing a multifocal version.
We can review how the lens centres, how stable it is, your pupil position and what you actually need from the lens at distance, computer and reading distances.
The optical design can then potentially be modified while retaining the aspects of the scleral fit that are already working well.
Who Might Consider a Multifocal Upgrade?
It may be worth discussing if your current scleral lenses give good distance vision but you now find yourself:
using reading glasses constantly, struggling with your phone, moving computer screens further away, swapping between several pairs of glasses, or wanting greater independence from readers during work and daily activities.
It can also be useful for patients receiving new scleral lenses who already know that both distance and near vision are important.
What If the First Multifocal Design Isn’t Perfect?
Multifocal scleral fitting may require fine-tuning.
Patients often need to wear the lenses in their normal environment before they can accurately tell us what needs changing.
For example, you might discover that:
distance vision is excellent but computer vision needs more support,
or that reading is excellent but you want slightly better night-driving vision.
Because the optics can be customised, we can use this real-world feedback to adjust the balance.
The fitting process is therefore not simply:
“Here is a multifocal lens—hopefully it works.”
It is a process of determining which optical configuration best suits that particular patient.
Will I Still Need Reading Glasses Sometimes?
Possibly.
The aim is usually to reduce dependence on reading glasses, rather than promise that you will never need them again.
Very small print, prolonged close work, poor lighting or particularly demanding visual tasks may still be easier with additional reading correction.
For many patients, however, even reducing how often they need to reach for reading glasses can make a significant difference to daily convenience.
Are Multifocal Scleral Lenses Suitable for Everyone?
No.
We generally want the underlying scleral lens fit and distance vision to be reasonably successful before introducing multifocal optics.
Some patients may obtain better overall vision with alternatives such as:
single-vision scleral lenses with reading glasses,
modified monovision,
different optical emphasis between the two eyes,
or another contact-lens strategy.
The best approach depends on the patient’s cornea, lens fit, visual demands and expectations.
Custom Multifocal Scleral Lenses at Westmead Eyes
At Westmead Eyes, multifocal scleral lenses can be custom designed rather than using one standard optical configuration for every patient.
Kevin Trac can adjust the optical design according to factors such as lens centration, pupil size and the patient’s preferred balance between:
distance → computer → reading
This is particularly useful for patients with complex corneas where the scleral lens fit is already highly customised.
The same principle can then be applied to the optics.
Already Wearing Scleral Lenses and Want to Reduce Your Dependence on Reading Glasses?
If your existing scleral lenses are comfortable and providing good distance vision, they may be suitable as the basis for a customised multifocal upgrade.
We can review your existing lens fit and discuss where you need better vision—whether that is your phone, computer, reading material or a combination of distances.
Interested in multifocal scleral lenses?
Please book a Scleral Lens Consultation with Kevin Trac.
You can also learn more about our specialised lens fitting:
Multifocal scleral lenses are not suitable for every patient, and the achievable balance between distance and near vision varies between individuals. An assessment is required to determine the most appropriate design.