Cataract patients want to choose the “best” IOL before surgery, and even believe that the most expensive IOL is the best, fearing that choosing the wrong one will affect their post-operative vision. We already know that IOLs are implanted in the eye to replace the function of the original lens and to focus the image in the original position so that the eye can see objects clearly. As long as the material used to make the IOL is non-toxic, well-made, and tightly sterilized, the effect is the same after implantation. However, for diabetic cataracts or secondary cataracts, we recommend the use of drug-treated IOLs to reduce post-operative reactions.