Seeing Better: Optimizing Surgically Induced Astigmatism Correction Factors for Cataract Surgery

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Milne, Erin
Winkler, Nelson
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Cataract surgery is one of the most common operations performed in the United States each year [1]. Cataract surgery is seen as a 'routine' procedure; however, it is not without complications. The surgery changes the natural astigmatism of the eye, which can cause blurry vision. It is possible to correct for the surgically induced astigmatism (SIA) during the operation. Currently, a standard correction factor of 0.5 diopters (D) is used. While this correction facto produces respectable results, we endeavored to improve upon the model and deliver individualized SIA predictions. The goal of this article is to predict the SIA for sue in surgery on a second eye, based upon prior surgical results from the same patient. Pre-operative and post-operative cataract surgery fata was gathered from a private ophthalmology practice. SIA values were then calculated, and a two-sample t-test was done to compare the mean values for left and right eyes. When no significant difference was found, we performed regression analysis to determine a model for SIA prediction. We analyzed our models using residual plots, a chi-squared test for goodness of fir, and generated a graphical comparison between our model and the standard correction factor of 0.5D. We found that our model is on par with the currently accepted standard correction factor and is, in fact, more accurate in cases of significant difference between the models. We believe we have generated a useful tool that can be easily and successfully utilized in patience care.