Impact Of Biconvex Lenticule On Depth Of Focus Post Lenticular Extraction Surgery With New Femtosecond Laser.

To analyze visual outcomes after lenticular extraction with new femtosecond laser (NFS)- ELITA  platform in terms of residual refractive error and ocular aberrations during accommodation, and compare with emmetropic (EM) eyes, eyes undergoing laser-assisted in situ keratomileusis (LASIK) and small incision lenticule extraction (SMILE).

Ocular aberrometry (Tracey Technologies, Houston, TX) was performed 3 months after NFS (n=70), and after traditional LASIK (n=92) and SMILE (n=74) surgeries. Ocular aberrometry was measured using distance (6 m) intermediate (60 cm) and near (40 cm) reading targets. Similarly, ocular aberrometry was also performed in a group of age-matched EM eyes (n=50) with visual acuity of 20/20. The refractive and aberrometric status at various degrees of accommodation was compared across these surgery groups using Kruskal-Wallis test.

Spherical aberration (SA) in EM and NFS was significantly different from LASIK and SMILE for intermediate (p<0.001) and distant (p<0.001) targets. SA of EM and NFS was significantly different from SMILE (p=0.03) for near target. Defocus in EM and NFS was significantly different from LASIK and SMILE for intermediate (p<0.001) and near (p<0.001) targets. Defocus was not significantly different between groups for distance target (P=0.08). Spherical equivalent (SE) in EM and NFS was significantly different from LASIK and SMILE for near (p<0.001) and distant (p<0.001) targets. SE was not significantly different between groups for intermediate target (p=0.14).