Corneal Wavefront-Guided Retreatments for Significant Night Vision Symptoms after Myopic Laser Refractive Surgery

Purpose

To evaluate the results of corneal wavefront (WF)-guided enhancements in patients with night vision symptoms and significantly high positive spherical aberration (SA) after myopic laser refractive surgery.

Design

Noncomparative, interventional case series.

Methods

Twenty-eight eyes of 20 patients with significant night vision symptoms and positive corneal SA (Z₄⁰) higher than 0.5 μm after myopic laser refractive surgery were included in the study at Vissum-Instituto Oftalmologico de Alicante, Spain. Enhancement surgery was planned to remove residual refractive error and corneal SA (Z₄⁰) in all cases. All patients underwent corneal WF-guided excimer laser retreatments using the ESIRIS/SCHWIND excimer laser system (Schwind Eye Tech Solutions, Kleinostham, Germany). The main outcome measures were visual symptoms, change in corneal SA (Z₄⁰), and corneal asphericity (Q-value).

Results

Subjective reports of night vision symptoms were improved in all patients. Mean corneal SA (Z₄⁰) decreased from 0.75 ± 0.19 μm before surgery to 0.43 ± 0.42 μm after surgery (P < .001). Mean asphericity in the 4.5-mm zone significantly decreased from 1.02 ± 1.07 before surgery to 0.52 ± 0.88 after surgery (P = .008), and the mean asphericity in 8 mm did not change significantly (P = .362). The mean spherical equivalent significantly shifted to hyperopia from −0.22 ± 1.14 diopters (D) before surgery to 0.33 ± 0.54 D after surgery (P = .025).

Conclusions

Cornea wavefront-guided retreatment was effective in improving subjective night vision symptoms, reducing corneal SA, and decreasing asphericity in eyes that underwent myopic laser refractive surgery.