Corneal densitometry and topography after femtosecond laser-assisted laser in-situ keratomileusis compared with small-incision lenticule extraction

Purpose The aim of this study was to compare between femtosecond laser-assisted laser in-situ keratomileusis (FS-LASIK) and small-incision lenticule extraction (SMILE) regarding corneal densitometry (CD) and corneal topography. Setting The study was conducted at Department of Ophthalmology, Faculty of Medicine, University of Alexandria, Alexandria, Egypt. Patients and methods The study included 60 eyes of 30 patients divided into two equal groups: 30 eyes were treated using FS-LASIK and 30 eyes were treated using SMILE surgery for myopia and myopic astigmatism to evaluate CD and topography before and after 1 week and 2 months postoperatively using Pentacam HR. Results There was an insignificant difference between the two groups in CD preoperatively (P=0.154), 1 week postoperatively (P=0.180), and 2 months postoperatively (P=0.138). In FS-LASIK group, there was a significant flattening in keratometric values (K1 and K2) of anterior corneal surface as the mean of K1 was 36.33±1.45 and 36.24±1.43 D and the mean of K2 was 37.09±1.55 and 37.00±1.52 D in comparison between 1-week postoperative and 2-month postoperative follow-up visits, respectively. There was an insignificant difference between the two groups in K1 and K2 of the posterior surface preoperatively, 1 week postoperatively, and 2 months postoperatively. Conclusion There was an insignificant difference between the two groups in CD. In the anterior surface, FS-LASIK exhibited more flattening in K1 and K2 than SMILE. Regarding the posterior surface, there was an insignificant difference between FS-LASIK and SMILE.