‘Super Surface’ and ‘Super Formula’ concepts increase IOL calculation accuracy

IOL power calculations for cataract surgery have come a long way since the days of empiric regression formulae such as the SRK and SRK II. We now tend to use theoretical methods such as the Holladay, SRK/T, Hoffer Q and Haigis, among others. While we think of these formulae as two-dimensional entities, there is a benefit of plotting them in three dimensions. John Ladas, MD, PhD, had an idea: Could a graphical solution be used to solve the complex mathematical problem of IOL power calculation? The concept that he came up with is a novel method of characterizing and conceptualizing IOL formulae in three dimensions to ease interpretation and visualization. Current formulae such as the Holladay, Haigis, Hoffer and Sanders/Retzlaff/Kraff are very sophisticated and can be conceptualized better when seen in this manner. This method makes it easy to compare and analyze one formula vs. another or even all formulae at once.