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Updated: Jul 16, 2026

Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
Published on: September 16, 2025
[Study of torsional movements in refractive surgery]
Guilherme José Nunes Marques Rocha1, Otávio Siqueira Bisneto, Hamilton Moreira
1Hospital de Olhos de Paraná, Rua Cel. Dulcídio 199, 4o. andar, CEP 80420-170 Curitiba, PR. guigojnmr@hotmail.com
Purpose:
To observe torsional movements of the eye in refractive surgery, and their possible consequences in the surgery outcome.
Methods:
In a prospective study, 49 eyes of 40 patients were submitted to surgical correction of astigmatism, by the LASIK technique. Patients were divided in two groups based on the cylindric power. Group A from -0.25 to -2.00D; group B from -2.25 to -6.00D. The occurrence of torsional movements was recorded in all patients, and based on this, the axis of treatment was corrected.
Results:
Mean torsion was 3.5 masculine +/- in group A; and 4.5 masculine+/- in group B. There was no statistical difference between the two groups.
Conclusion:
Torsional movements occurred in almost all cases, and therefore should be corrected if one desires best results. This is specially important in matching personalized data captured in wave front analyzers for the eye at the time of surgery.
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