Selection of the method for additional correction of ametropia after previous femtosecond laser lenticule correction of myopia and myopic astigmatism using CLEAR technique

OBJECTIVE: The study presents 3 options for additional correction of ametropia after previous femtosecond laser correction of myopia and myopic astigmatism using the corneal lenticule extraction for advance refractive correction (CLEAR) technique. MATERIAL AND METHODS: The study included 3 patients (3 eyes). After CLEAR surgery, patient 1 had uncorrected visual acuity (UCVA) in the left eye (OS) of 0.8 with correction sph (+)0.25 cyl (+)1.0ax113=1.0; in patient 2 UCVA OS was 0.4 with correction sph (-)1.25 cyl (-)0.25ax134=1.0; in patient 3 UCVA OS was 0.4 with correction cyl (-)1.75-42=1.0. In the first case, the corneal flap was created mechanically, in the second case, a 3D corneal flap edge was created using the Femto Z8 femtosecond laser system, and in the third case, a 2D corneal flap edge was created using the same system. Excimer laser ablation of residual ametropia was then performed in all cases. RESULTS: The surgeries were completed without complications. UCVA of 1.0 was achieved in all cases. CONCLUSION: Post-CLEAR ametropia correction is possible by shaping the edge of the corneal flap using a mechanical method, as well as using the Femto Z8 femtosecond laser system with the "side-cut-only" and "border-cut-only" programs.