Z-adjust topography-Guided Laser in Situ Keratomileusis (LASIK) for eccentric cutting induced by LASIK keratorefractive surgery

Objective: To evaluate the clinical efficacy of Z-adjust topography-guided customized laser in situ keratomileusis (LASIK) for eccentric cutting induced by LASIK keratorefractive surgery. Methods: In this retrospective case series study, 10 eyes of 8 patients with eccentric cutting induced by LASIK surgery from June 2008 to December 2014 at Chinese PLA the 401th Hospital were enrolled. The patients were treated with Z-adjust topography-guided LASIK. The uncorrected visual acuity (UCVA), refractive status, corneal Q-value (which describes the corneal aspherical quality), and corneal keratometry were analyzed and compared. Results: The pre-operation UCVA (LogMAR) of all patients was 0.3 to 0.6, and the post-operative UCVA (LogMAR) improved significantly was -0.1 to 0.1. The corneal Q-value increased significantly from 1.26±1.55 diopter (D) (range 0.26 to 2.25 D) pre-operative to 0.28±0.35 D (range -0.27 to 0.50 D) at 3 months post-operative. The corneal keratometry decreased significantly from 40.98±3.56 D (range 39.25 to 43.50 D) to 37.32±1.47 D (range 36.25 to 38.50 D). The scotopic pupil diameter increased significantly from 5.9±0.4 mm (range 5.5 to 6.1 mm) to 6.8±1.1 mm (range 6.0 to 7.4 mm). The Z-adjust range for the X axis was adjusted from +0.005 to +0.052 mm, and for the Y axis, it was adjusted from +0.007 to +0.045 mm. Conclusions: The eccentric cutting of all eyes were corrected by Z-adjust topography-guided customized LASIK surgery, and the visual quality was greatly improved. Key words: eccentric cutting; laser in situ keratomileusis; corneal topography