Accommodation is the result of a complex mechanism that starts up when vision switches from far away to up close, and which aim is to enable us to see properly focused and sharp images from any distance. To this purpose, the crystalline, which is the natural lens we have inside the eye created to focus, changes its shape automatically in relation to the distance of the object, at such a speed, that we don’t even realise of this fact.
Age-related long-sightedness or presbyopia is a physiological phenomenon that occurs as a result of the “wear and tear” of the accommodation mechanism in all people from the age of 40 onwards. Crystalline gradually becomes rigid losing its capacity to focus on nearby objects which compels us to use reading glasses, at first. As we grow older, this situation worsens, mid-distance vision (8”) also fails and we need a different refraction power from the up close one (16”). In the end, to balance this problem as a whole, we need wearing multifocal glasses which main property is having numerous focus for many distances. Unfortunately, this phenomenon causes such a dependence on glasses to the extent that we just can’t manage without them.
Taking into account that the aging of the crystalline is responsible for this condition, it was concluded that if we were capable of replacing it for an intraocular lens that performed its function, the problem could be solved. In order to achieve this goal, the optical industry has been investigating for a long time how age-related long- sightedness could be supplemented by designing increasingly perfected lenses so that nowadays we have moved from bifocal lenses, which used to provide both far away and up close good quality vision, to trifocal lenses that provide mid-distance fine vision too, including astigmatism correction. These studies keep evolving continuously and, in years to come, we will undoubtedly see new designs and improvements that will go beyond the current models.
The surgical procedure is superimposable and as safe as the cataract surgery. In this case though, the crystalline is transparent. The refractive result obtained can be reckoned to be stable and doesn’t suffer any change over the years.
Despite this kind of surgery can be performed simultaneously on the same day, we firmly advice patients against this procedure and we operate on the second eye a week or a fortnight afterwards.