Changes in corneal biomechanics during small-incision lenticule extraction (SMILE) and femtosecond-assisted laser in situ keratomileusis (FS-LASIK)

AbstractObserve the influence of femtosecond laser cutting on corneal biomechanics during small-incision lenticule extraction (SMILE) or femtosecond-assisted laser in situ keratomileusis (FS-LASIK) and assess the biomechanical changes following the operation. Prospective, non-randomized study. A total of 80 eyes from 80 patients were treated with either SMILE or FS-LASIK. Parameters of inverse concave radius, deformation amplitude ratio 2  mm or 1 mm (DA ratio 2 mm or 1 mm), highest concavity radius (HC radius), biomechanically corrected intraocular pressure (bIOP), and central corneal thickness (CCT) measured by Corvis ST II were recorded at 1 day preoperatively, immediately after the lenticule or flap creation, during subseque nt lenticule extraction or excimer laser ablation, and during follow-up at 1 week, 1 month and 3 months postoperatively. After lenticule creation, the DA ratio 2 mm or 1 mm was bigger (p <  0.05), meanwhile, CCT was thicker (p <  0.05) than with flap creation. Partial parameters changed significantly after lenticule creation or flap creation, and all parameters changed significantly after tissue removal. All parameters showed no significant differences between the two groups (p >  0.05) after operation. The variations in bIOP (ΔbIOP) after operation were significantly less than those in Δnon-contact IOP (p <  0.001) in two groups. Femtosecond laser cutting during lenticule creation has a greater impact on cornea...
Source: Lasers in Medical Science - Category: Laser Surgery Source Type: research