Dysphotopsias and PCO

The Alcon lenses like the AcrySof IQ have gained a reputation (deserved or not) for being more resistant to PCO. This is thought to be due to the specific material used for the lens plus the use of sharp square edges on the lens. The sharp edges are thought to prevent the growth of cells that cause the PCO. The were among the first to use the sharp edges, but now almost all lens manufacturers use sharp square edges. However there remains issues due to the material and manufacturing methods as to how sharp they can actually make the square edges. Alcon's latest Clareon material is claimed to allow sharper more polished edges and that it has reduced the incidence of PCO and the need to do YAG to lower levels than the AcrySof material.

Neither Alcon nor Tecnis, but Sofport Li61AO. Take that one.

I would also prefer an IOL with a circular sharp edge (e.g. Sofport, Kowa cp2.2.r, Bausch&Lomb Envista).

The circular edge could prevent ingress of epithelial cells better than a sharp edge around the haptics (Alcon). Kowa has a comparison on their website showing edges of different lenses.

To minimise refractive surprises, a one pice IOL is better be than a three piece, by keeping its ELP.

Shown in this paper:

"Geometry of Acrylic, Hydrophobic IOLs and Changes in Haptic–Capsular Bag Relationship According

to Compression and Different Well Diameters: A Bench Study Using Computed Tomography"

In an earlier post you said you were looking for toric IOLs. Have you had your eyes measured to see if a toric lens is justified or not? If you have eyeglasses with astigmatism correction in them that is not a definitive indication that you need a toric lens. Astigmatism can be in the cornea or lens. When you have cataract surgery the natural lens is broken up and removed, so any astigmatism in the lens is gone. This means you will only be left with the astigmatism in the cornea. It may or may not be enough to merit a toric lens. Generally if the predicted cylinder is less than 0.75 D then a toric is not recommended. And, of course if you plan to wear glasses astigmatism can be corrected by the glasses. If you plan to be eyeglass free then getting a toric lens if the cylinder is large enough is a good idea.

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I raise the issue as there are other things to consider in addition to PCO resistance and dysphotopsia. Astigmatism correction in eyeglasses is fixed at the specified angle in your prescription. It can't change after your lenses are made. In an IOL the lens has cylinder built into it, but no specified angle. The surgeon has to insert the lens and rotate it into the correct angular position to provide the correct cylinder correction. For that reason it is important that the IOL stays in this correct position. The Alcon AcrySof lenses (deservedly or not) have gained a reputation for being sticky and staying put. For this reason they have been the most popular toric lens used.

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The other issue with toric lenses is that they come in quite large steps in cylinder power, and not all torics go down to the same minimum cylinder power. If your predicted cylinder is in the 0.75 D range then some manufacturers will not have a power low enough to avoid an over correction. The last time I checked the Clareon Toric for example is not available in as low a power as the AcrySof IQ Toric.

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All things considered along with your plan to travel to get your surgery, you may want to consider getting an initial assessment and the measurements take locally (if available) to find out where you stand for needing a toric, and if so how much. That may narrow down your choice for a lens quite a bit. And you also have to consider when looking for a surgeon is that many do not offer all brands of lenses and will be limited in your choices. Often when you pick your surgeon, you are also picking your brand and availability. If you do this make sure to ask for a copy of the IOL Calculation measurements.

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One thing that may be of interest to you is what lenses are actually being used by surgeons. The article below shows some data on what lenses are being selected based on a survey of surgeons, I believe in the US. You will not see all lenses listed in this survey. For example I suspect the new Clareon lenses are lumped in under the generic Alcon line.

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Review of Ophthalmology PUBLISHED 10 JANUARY 2023 Cataract Surgeons Embrace New Options

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Hope that helps some