Q-value individualized CLEAR lenticule extraction preserves corneal asphericity and minimizes spherical aberration while maintaining optical zone predictability

Refractive surgery enhances visual performance by reshaping the cornea. At the same time, optical aberrations typically increase, affecting visual quality. An essential factor for minimizing the induction of optical aberrations after refractive surgery is the preservation of corneal asphericity. To address this challenge, corneal lenticule extraction for advanced refractive correction (CLEAR) considers individual Q-values to generate an aspheric laser resection profile. This study aims to evaluate the effect of CLEAR on corneal asphericity, spherical aberration and optical zone diameter. Sixty eyes of 30 patients underwent refractive correction for myopia or compound myopic astigmatism with the CLEAR application. Three months postoperatively, the Q-value increased from - 0.13 ± 0.09 to 0.01 ± 0.27, resulting in an oblate shift of 0.14 ± 0.25 from the preoperative state. The preoperative SA was 0.24 ± 0.06 μm, remaining stable at 0.24 ± 0.13 μm postoperatively. The planned optical zone of 6.50 mm resulted in an achieved effective optical zone of 5.93 ± 0.40 mm, a mean reduction of -0.57 ± 0.40 mm. Therefore, myopia and compound myopic astigmatism correction with CLEAR resulted in minimal positive shift in Q-value, limited difference between planned and effective optical zone, and no overall induction of spherical aberration.