Corneal ultrastructure, wound healing and inflammation after SMILE and femtosecond LASIK: a human ex vivo study
Session Details
Session Title: Presented Poster Session: Keratorefractive Results II
Venue: Poster Village: Pod 2
First Author: : N.Luft AUSTRIA
Co Author(s): : R. Schumann R. Scheler M. Dirisamer T. Kreutzer S. Priglinger W. Mayer
Abstract Details
Purpose:
Aim of this study was to assess corneal ultrastructure, wound healing and inflammation after small incision lenticule extraction (SMILE) and femtosecond laser-in situ keratomileusis (fs-LASIK) by means of scanning electron microscopy as well as immunofluorescence analysis.
Setting:
University Eye Hospital, Ludwig-Maximilians-University, Munich, Germany
Methods:
Sixteen eyes of 16 human donors unsuitable for transplantation were obtained from the eye bank of our institution. Eight eyes underwent SMILE with -5.00 diopters (D) of myopic correction utilizing the VisuMax 500-kHz femtosecond laser (Carl Zeiss Meditec AG; Jena, Germany), five eyes were subjected to fs-LASIK with -5.00D ablation (VisuMax & Wavelight Allegretto Eye-Q 400Hz; Alcon; Fort Worth, Texas, USA) and three donor eyes served as control group without surgical intervention. Postoperatively, specimens were incubated in organ culture medium for 72 hours before being subjected to scanning electron microscopy (SEM) and immunofluorescence staining for CD11b, Ki67, fibronectin and TUNEL.
Results:
SEM analysis showed a smooth and uniform appearance of the SMILE lenticule surfaces and borders. Moreover, the ultrastructure of the corneal stromal bed was comparable between fs-LASIK and SMILE. Magnifications of 4,000x and higher allowed for visualization of singular femtosecond laser spots in the residual corneal bed as well as of the wound architecture at the incision. There was no significant difference in Ki67 activity as an indicator of keratocyte proliferation between SMILE and fs-LASIK. By staining for fibronectin, we observed a trend towards less pronounced corneal wound healing in the stromal bed after SMILE than after fs-LASIK.
Conclusions:
This initial ex vivo study of corneal ultrastructure after SMILE revealed smooth corneal bed interfaces as well as regular incision sites in human donor eyes. Immunofluorescence analysis indicated a less pronounced wound healing response after SMILE as compared with fs-LASIK.
Financial Disclosure:
NONE