Early spatial changes in the posterior corneal surface after laser in situ keratomileusis

Abstract

Increased forward shift of the posterior corneal surface is common after myopic LASIK and correlates with the residual corneal thickness and the ablation percentage per total corneal thickness. An excessively thin residual corneal bed or a large ablation percentage may increase the risk of iatrogenic complications.

Continuous monitoring of corneal thickness changes during LASIK with online optical coherence pachymetry

“…11 This underlines the problem of deriving the residual stromal thickness from calculated flap and ablation values 25 and suggests that a low residual stromal thickness is probably more frequent than estimated. This also confirms the assumption about continuous monitoring of corneal thickness changes intraoperatively.…”

Comparison of Forward Shift of Posterior Corneal Surface after Operation between LASIK and LASEK

“…The progression was most pronounced from 1 to 6 months, but had almost stabilized at 6 months [3] . Another study reported that the largest posterior corneal elevation shifted 1 week after LASIK [7] . The results in this study coincide with other reports showing that the largest forward shift in the posterior corneal surface occurred at the earliest time point between 1 and 2 weeks after refractive surgery in the LASIK and LASEK groups.…”

“…The increased forward shift of the posterior corneal surface correlates with the residual corneal thickness (RBT) and the ablation percentage per total corneal thickness (P/TCT) [7] . However, an examination of the changes in the posterior corneal surface according to the level of corneal tissue subtraction after LASIK and LASEK is rarely performed.…”

The change in internal aberrations following myopic corneal laser refractive surgery

“…There are a number of possible causes for this measured change in internal HOA. A change may occur to the posterior cornea [21,22], which is supported by slit-scanning topography studies indicating changes occur to the posterior cornea following LASIK [24][25][26][27][28][29][30][31][32][33][34][35][36]. However, some slit-scanning topography studies have found no changes to the posterior cornea post-LASIK [37,38], and Ueda et al [39] demonstrated that these posterior corneal changes are artefacts due to changes in the magnification ratio.…”