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Accuracy of Astigmatism Calculation with the Barrett, Panacea, and enVista Toric Calculators
Astrid Lucero Espinosa Soto1, Jimena Ceja Martínez1, Rosario Gulias-Cañizo2,3
1Department of Anterior Segment Surgery, Fundación Hospital Nuestra Señora de la Luz, Mexico City 06030, Mexico.
Purpose:
To evaluate residual refractive astigmatism using the Panacea and enVista toric calculators, compared to the gold-standard Barrett toric calculator.
Design:
A retrospective and comparative study was conducted in one center.
Methods:
We reviewed the medical records of all patients with a diagnosis of senile cataracts and regular corneal astigmatism, without previous corneal or intraocular surgery, who underwent phacoemulsification with implantation of a toric intraocular lens, who had pre- and postoperative corneal topography, biometry, and refraction measurements.
Results:
The frequency of preoperative astigmatism according to the axis was 70 (84%) eyes showing with-the-rule (WTR) astigmatism, 9 (14%) eyes with against-the-rule (ATR) astigmatism, and 1 (2%) eye with oblique astigmatism. Regarding astigmatism prediction errors, there were statistically significant differences between the enVista and Panacea calculators (median of 0.39, 0.18, and 0.52 for Barrett, enVista, and Panacea, respectively). The residual astigmatism prediction error centroid was similar for the Barrett and enVista toric calculators, and both were lower compared to the Panacea calculator (x-component p < 0.001).
Conclusions:
The enVista toric calculator incorporating the Emmetropia Verifying Optical (EVO) toric calculator provides similar results to the gold-standard Barrett calculator.
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