Thank you for the letter regarding the predictability information in our recent publication "Astigmatism Reduction Clinical Trial: A Multicenter Prospective Evaluation of the Predictability of Arcuate Keratotomy."1 The confusion arises over the interpretation of the results presented in Table 5. Predicted results in Table 5 are provided for male patients, but note that 69% of our study participants were women. Our results indicated a strong gender effect, with women averaging 0.37 D less effect than men. If you subtract 0.37 from each result in the "revised" formula in Table 5, you see many more lower predicted results with the revised nomogram. However, where the revised formula shows a greater predicted result, the revised nomogram should be used—such as for the 30-year-old with 2 D of astigmatism—if your goal is a conservative result. The two incisions at 30° and two incisions at 45° plans are the instances in
Price FW, Marks RG, Gonzales JS. Astigmatism Reduction Clinical Trial-Reply. Arch Ophthalmol. 1995;113(10):1226. doi:10.1001/archopht.1995.01100100014005
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