Eyeworld

DECEMBER 2022 | EYEWORLD | 17 References 1. Wang L, Koch DD. Intraoc- ular lens power calculations in eyes with previous corneal refractive surgery: review and expert opinion. Ophthalmology. 2021;128:e121–e131. 2. Randleman JB, et al. Intra- ocular lens power calculations after laser in situ keratomileusis. Cornea. 2002;21:751–755. 3. Wen D, et al. Network meta-analysis of no-history methods to calculate intraocular lens power in eyes with previous myopic laser refractive surgery. J Refract Surg. 2020;36:481–490. 4. Wang L, et al. Evaluation of intraocular lens power prediction methods using the American So- ciety of Cataract and Refractive Surgeons post-keratorefractive intraocular lens power calcu- lator. J Cataract Refract Surg. 2010;36:1466–1473. 5. Pantanelli SM, et al. Intraoc- ular lens power calculation in eyes with previous excimer laser surgery for myopia: a report by the American Academy of Ophthalmology. Ophthalmology. 2021;128:781–792. 6. Vrijman V, et al. Evaluation of different IOL calculation formulas of the ASCRS calculator in eyes after corneal refractive laser surgery for myopia with multifocal IOL implantation. J Refract Surg. 2019;35:54–59. 7. Abulafia A, et al. Accuracy of the Barrett True-K formula for intraocular lens power prediction after laser in situ keratomileusis or photorefractive keratectomy for myopia. J Cataract Refract Surg. 2016;42:363–369. and no outliers were detected in the biometry measurements. Discussion This study demonstrated the advantages of the Barrett True-K formula in eyes for both post-my- opic and post-hyperopic ablation. The authors demonstrated how the Barrett True-K formula produced the highest proportion of eyes within 0.25 D and 0.50 D of the target refraction, lowest mean and absolute refractive error, and lowest standard deviation of those errors. In ad- dition, for 12 post-myopic and 6 post-hyperopic outliers, the Barrett True-K still outperformed all other formulas. This finding is significant because the Barrett True-K formula is embedded into the IOLMaster and Lenstar, improving convenience and eliminating the possibility for transcription error when transferring data into the online diction errors were also analyzed. There was a statistically significant difference in the varianc- es between the absolute refractive errors of all calculators, and post-hoc paired t-tests showed that the Barrett True-K also had the lowest stan- dard deviation and residual absolute refractive error compared to all other formulas for both myopic and hyperopic ablations. In addition, the Barrett True-K achieved the highest proportion of eyes with postop refrac- tion within 0.25 D (44.8%) and within 0.50 D (71.9%), though this difference was not statisti- cally different from the ASCRS mean proportion (38.3% for within 0.25 D and 65.6% within 0.50 D). Outlier analysis was also performed for eyes with greater than 1.00 D of IOL prediction error. In 12 post-myopic eyes and 6 post-hy- peropic eyes where the IOL prediction error of the Barrett True-K was greater than 1.00 D, no other formula outperformed the Barrett True-K, continued on page 18 From left: Sri Meghana Konda, MD, Ellis Wisely, MD, Cason Robbins, MD, James Tian, MD, and Pratap Challa, MD Source: Duke University

• Blank Page
• Blank Page (1)