During cataract surgery, your eye's natural lens is removed and replaced with an intra-ocular lens (IOL). I will arrange for special investigations to work out what lens power to use. A standard monofocal lens will aim to give you great distance vision but it will mean that everything close up is blurry. You will require reading glasses for near vision such as reading and also for your intermediate vision, for example reading your tablet or computer. A multi-focal lens is designed to give you good near, intermediate and distance vision.
The technology is not perfect and it will not give you perfect distance and near vision but it should be pretty close. The vast majority of patients I have implanted with these lenses have found themselves independent of spectacles.
These lenses take the light energy and split it off into different focusing points. The brain gets two or three in focus images on the retina and it has to learn which one to notice and which to “see”. Once your brain adapts to the new way of seeing it will recognise what image it needs to use and ignore the other image(s).
Multifocal lenses deliver amazing results but they do have some compromises. They are not for everyone. We will need to decide together whether they are suitable for you once we assess your lifestyle, visual needs, clinical status and motivation for spectacle independence.
Not truly a multifocal lens but a premium lens nonetheless. With ordinary NHS cataract surgery patients have a lens that sets them for distance. This is great for the majority but some patients struggle with intermediate vision; using the computer, seeing labels on food goods, seeing the speedometer in the car etc.
To address this Tecnis have developed the Eyhance Intraocular Lens™. It gives superb distance vision but also has a central segment with more power in order to allow a greater depth of focus.
Greater flexibility with vision has a big impact on quality of life.
It must be emphasised that these lenses do not give true distance and intermediate vision. They simply make the intermediate vision a bit clearer. For true distance and near/intermediate vision patients should opt for the other lenses detailed on this page.
I will now be implanting all my private patients who need monofocal lenses with the Eyhance Intraocular Lens™, a premium lens which delivers over and above the ordinary NHS lens.
Zeiss AT Lisa
The AT Lisa (Zeiss) has multiple concentric rings to focus the light in different places. It looks a bit like the glass lens you see on a lighthouse light. The presence of those concentric rings cannot be completely problem free and glare is almost inevitable but thankfully tolerable in the vast majority of patients. Also because the energy of the light is split/reduced for each focal distance it means that if you have any problem with the macula (such as age related macular degeneration/wear and tear) this is not the lens for you.
Zeiss AT Lara
This is a new lens from Zeiss which is described as an extended depth of focus lens (EDOF). Rather than splitting the light energy off into three distinct zones it blends the light energy over a greater depth of field. This gives you good distance and intermediate vision but near vision tends to be more of a struggle. This type of lens is ideal for those who want the benefit of a premium lens without the risk of visual side effects such as halos.
Precizon™ Presbyopia Correcting IOL
This is a refractive IOL and has separate distance and near segments in a new innovative design. It negates the potential glare and adverse light effects of the rings of some of the other premium lenses and transmits more light energy.
DUET Double Lens System
There are problems that can occur with multifocal lenses. Some patients get glare and some notice a reduction in light energy. One in a hundred patients may need their multifocal lens removed and replaced. In later life we are also more dependent on light energy so having a reversible procedure seems desirable.
To allow a safety net I have adopted the new DUET technique whereby a monofocal lens is placed into the usual position and a specifically designed multifocal lens is placed in front of that to facilitate the distance and near vision. This delivers the best of both worlds and allows us to remove the multifocal lens with ease in the future.
Looking for Perfection?
If you want perfection then these will not give it to you but they will give you good quality vision. If you want a compromise and get good near and distance vision with the potential of a few visual side effects which are usually not particularly troublesome then these lenses could be an option for you. I try my best to give some degree of spectacle independence however there are no guarantees. Even if things go completely to plan there are some patients that still require spectacles.
What You Should Know Before Considering a Multifocal IOL
Particularly with multifocal IOLs, you must be prepared for the possibility of at least some visual distortions — particularly in the form of glare and halos around light sources at night. These distortions rarely stop you night driving but in some people they can be annoying. If night driving is vital for you (for example if you are a lorry or taxi driver) then I would not recommend a multifocal lens.
Other reasons you may be eliminated as a candidate for multifocal IOLs include:
- Astigmatism does not exclude you as toric lenses are available that correct the astigmatism for you by putting the astigmatism correction into the lens itself.
- Other eye problems, such as retinal diseases, which would reduce the quality of your vision.
If you have already had cataract surgery but been left with poor near and/or intermediate vision and are thus still reliant on spectacles there is an option of putting another "top-up" intraocular lens into the eye to correct this without the need for spectacles - the Sulcoflex® Multifocal IOL.