Centration Strategies in Refractive Surgery: The Role of Angle Kappa in Mixed Astigmatism

A bstract Accurate centration of laser ablation is a key determinant of visual outcomes in refractive surgery, particularly in eyes with hyperopia and mixed astigmatism. Angle kappa, representing the offset between the visual axis and the pupillary axis, is often larger in these refractive errors and may significantly influence ablation alignment. Failure to account for an increased angle kappa can result in decentered ablation, residual refractive error, higher-order aberrations, and postoperative visual disturbances. In a patient with mixed astigmatism and a large angle kappa, femtosecond-assisted LASIK with wavefront-optimized ablation centered between the pupillary center and corneal light reflex resulted in well-centered ablation and excellent visual outcomes without visual symptoms. This report underscores the importance of routine preoperative evaluation of angle kappa and individualized centration strategies to optimize visual quality and patient satisfaction in refractive surgery.