While many don’t think there is a difference between short-sightedness and presbyopia, the reality is that they are two separate issues that can exist at the same time. Presbyopia is ageing of the eyes, so we all go through that regardless whether long-sighted, or we have perfect distance vision or are short-sighted. Short-sightedness is where the optics of the eye are too powerful. So light from distance and the light rays come parallel when they reach the eye, the image is focused in front of the retina, and so the image on the retina is blurry.

Shortsighted people have to wear divergent lens either as a contact lens or spectacle lens to achieve clear focus. When short-sighted people then develop presbyopia, the lens inside their eye becomes rigid, and they lose that ability to shift focus. If you’re a short-sighted person who, let’s say has got a prescription of minus 3, you could wear your minus three spectacles when you’re 30 years old and see right out to the horizon and then accommodate and see up-close through those spectacles. When you’re 50 and your minus 3, you can’t do that because you have presbyopia like all of us develop, and so with your minus three spectacles on you can see beautifully out in the distance, when you try and read up close, forget it. What short-sighted people can do is lift their specs up on their head and being minus three means that your peak focus the real clarity is about 30 centimetres away. So it’s quite a nice place to sit and read. Suddenly, being short-sighted isn’t so bad.

Let’s say you’re a chap whose minus 3 and your wife is the same age, presbyopic and also has great distance vision. Your wife can drive you both to the restaurant without spectacles, and you can read the menu without your spectacles. Between the two of you, there is a complete range of focus and a functional visual system. But you can’t do both.

When I’m looking after my short-sighted patients who have presbyopia, one of the things I do have to emphasise to them is that I’m going to take away that amazing vision they have at 30 centimetres because we want to put a lot of it out there where it’s all a complete blur. With both Lens Replacement and the Presbyond LASIK, there’s an element of sharing the light out, there’s an element of sharing the light, but there has to be because there are technologies that are excellent and very effective. They’re not like being 21 years old again, and they’re not seamlessly moving focus backwards and forwards.

I have to explain that we’re going to take away some of this amazing focus here to give something more useful and to give really good distance vision and intermediate vision and leave behind some pretty good near vision, but it can’t be quite as strong as no specs reading here. But it means you can drive to the restaurant.