How long will PRESBYOND results last?

In an interview, Dr Christoph Kranemann discusses how long the results of PRESBYOND vision correction will last.

Christoph Kranemann: What is changing is the lens. The lens in the eye gets bigger and stiffer.

The cornea

The part we’re working on is the window to the eye, which is what is called the cornea. That, typically, at this stage of life, is very stable. That will, generally, not change. We know from long-term studies of LASIK, and even PRK before, that for the vast majority of people the correction will be stable. The cornea will be stable, particularly when we’re utilising such tools as a curved-laser cutting approach where things will be extremely stable.

The lens

Certainly, our results over the last seven to eight years have really borne out that stability. Where there can be and will be some change, is the lens. However, we’re putting in that future change of the lens by, ideally, putting those three dioptres of reading correction into the system.

Cataract

There is the odd time where the eyes will not tolerate the full three dioptres and may be short by half a dioptre. That is really about the only time when there might need to a touch-up, two, three, five years later.

The only other things that will, possibly, change at some point down the road, is that the natural lens will diminish in the quality of light it lets through. Eventually, that will lead to clouding off that lens, which is otherwise commonly referred to as a cataract.

Because we’ve created a situation where the optical quality and functionalities are very good, it’s quite possible that you will be more sensitive to that quality of lens changes. You will notice something not right with the vision, probably sooner than somebody that has a full, and proper cataract. However, cataract surgery struggles to give you a full range of vision. Unless we do funny things with the lens, that involves a lens that has multiple focal points. This has a whole bunch of negative optical things and is often not greatly tolerated – we don’t have to worry about that in this case.

Duration of results

The benefit of PRESBYOND is that that changed cornea will stay with you probably for many decades, and quite possibly for the rest of your life. We can utilise that and marry that to a lens that doesn’t need to have multiple focal points, and still maintain that full range of vision while restoring the optical quality to as good, or better than it’s ever been.

To ensure that this will work, we’ve always and will continue always do measurements for future cataract surgery, before we do any laser vision correction. We will keep that information and obtain it before we do anything else.