August 31, 2015
The most demanding lens implant patient for me in regards to postoperative residual refractive error is the individual who has significant astigmatism and desires spectacle independent vision at all distances. While there are different surgeon preferences and lens implant approvals in each country, let’s presume we have access to and have chosen to use a bifocal or trifocal toric diffractive multifocal IOL.
My experience is that in order to achieve high patient satisfaction, I need to generate a refractive outcome with no more than 0.5 D of residual astigmatism and less than 0.5 D of residual spherical equivalent. There are many published series of refractive outcomes, including those from the United Kingdom, the Swedish registry and, closer to home, a large registry of cases accumulated by Guy Kezirian. These data sets suggest that with standard methods of optical biometry, astigmatism measurement and steeper meridian marking, the “typical surgeon” only achieves this outcome in 50% to 65% of cases.