Last month we talked about the success of cataract surgery, and one very important component is getting rid of the spectacle dependency as much as possible. This is directly dependent on the implantation of the correct intra-ocular lens. As with most things in life the successful outcome is very dependent on the surgeons’ effort in the calculation of the correct power of intra-ocular lens to be implanted. This process can be compared to using the correct contact lens to improve vision, but with cataract surgery this is more complicated.
The use of the newest laser techniques and software greatly helps with achieving accurate measurements of the eye to be treated, and then there is a multitude of possible calculation formulae used to calculate the strength of the intra-ocular lens. The reason for this is that no one formula is superior for all eyes.
In the largest study to date of 17 000 eyes the accuracy of cataract surgery was 71%. That translates to 71% of all operated eyes being close to the desired outcome with a very small spectacle error of 0,50 diopters or less. With some extra effort taken in the calculations the accuracy can be increased to approximately 83%. In my practice the accuracy is 85%. Additionally, the results within 1 diopter of the aimed result is 99,1% in my practice. This accuracy is contributable to many steps taken in order to improve the accuracy of cataract surgery.
The first and very important step is to use an intra-ocular lens from a reputable manufacturer that makes accurate lenses that enable reproducible results. Using the same intra-ocular lens for the past five years also enables me to analyze my outcomes. Every lens used is unique and has a specific result when implanted in the eye, and therefore the optimization is specific to the lens used. The analysis is not only to confirm the positive results, but more importantly enables optimization of the calculation formulae I use in the practice. By improving the software according to my personal results, the aim is to further improve the accuracy, increasing the accuracy for all patients, but especially so for difficult cases.