In the USA, the FDA has recently approved the Alcon PanOptix IOL for use in cataract surgery. This is a trifocal IOL design which is designed to give a wide range of vision using diffractive light-splitting technology. It is an improvement from its predecessors, particularly from certain bifocal designs. This lens has become popular in many countries outside the USA and has a significant rack record of success. But is it the fountain of youth for restoring great vision?
With diffractive IOLs, a trifocal design has the base curve plus two step heights which gives two focal points in addition to distance vision. If the near is 40 cm, then the intermediate must be twice this distance, or 80 cm. But 80 cm is just a bit too far for comfortable vision for intermediate tasks like computer or reading a menu.
A quadrifocal design has the base curve plus three step heights which give three focal points in addition to distance vision. If the near is 40 cm, then the next two steps will be 1.5x and 3x, or 60cm and 120 cm.
The new design of the PanOptix is actually a quadrifocal design where the optical engineers have adjusted the diffractive steps in order to push the 120cm point to improve the distance vision. This is a very clever optical design where the three effective focal points are distance vision, 60 cm (24 inches) for intermediate vision, and 40 cm (16 inches) for near vision.
Keep in mind that any degree of multifocality is still an optical compromise and that there is no free lunch. By splitting the light for intermediate and near vision, there will be two or more focal points on the retina and this is associated with the side effects of glare and halo, particularly at night.
So the Alcon PanOptix trifocal lens implant is a great choice for many patients, but like all man-made IOLs, it is not perfect. There are many factors which can influence its performance and patients need to discuss all options with their cataract surgeon before making a decision. Light-splitting technology is great, but keep in mind that the future will bring accommodating IOLs such as the LensGen Juvene that we world-premiered here months ago.
Nothing beats being a young and healthy human with an amazing, accommodating crystalline lens. But you already knew that!
Click below to learn more about the Alcon PanOptix IOL:
