Review of Corneal Biomechanical Properties Following LASIK and SMILE for Myopia and Myopic Astigmatism

Iben Bach Damgaard1, *, Mohamed Reffat2, Jesper Hjortdal1
1 Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark.
2 Mansoura Ophthalmic Hospital, Mansoura, Egypt


Worldwide, femtosecond laser assisted in-situ keratomileusis (LASIK) is a well known and commonly used refractive technique, although Small Incision Lenticule Extraction (SMILE) has become increasingly popular since it was introduced in 2011. In LASIK, a corneal flap is cut with a microkeratome or femtosecond laser, followed by thinning of the stromal bed with excimer laser ablation. In SMILE, a minor intrastromal lenticule is cut with a femtosecond laser and subsequently removed through a small incision, leaving the anterior and strongest part of the cornea almost intact. Both LASIK and SMILE require cutting of corneal lamellae that may reduce the biomechanical stability of the cornea, with the potential risk of corneal iatrogenic ectasia as a severe complication. However, SMILE preserves the anterior corneal integrity and may, in theory, better preserve the corneal biomechanical strength than LASIK after surgery.

This review aimed to examine the current literature that describes and compares the corneal biomechanical properties after laser assisted in-situ keratomileusis (LASIK) and small incision lenticule extraction (SMILE). A comprehensive search was performed in using the following search queries: Corneal biomechanical properties, corneal biomechanics, ocular response analyser, ocular response analyzer, ORA, ex vivo, in vitro, Corvis, Corvis ST, LASIK, and SMILE.

Abstract Information

Identifiers and Pagination:

Year: 2018
Volume: 12
Publisher Item Identifier: EA-TOOPHTJ-2018-HT1-266-4

Article History:

Received Date: 19/10/2017
Revision Received Date: 08/01/2018
Acceptance Date: 20/01/2018
Electronic publication date: 30/5/2018
Collection year: 2018

© 2018 Damgaard et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: ( This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Correspondence: Address correspondence to this author at the Department of Ophthalmology, Aarhus University Hospital, Noerrebrogade 44, Building 10, 2nd floor, 8000 Aarhus C, Denmark; Tel: +45 25522506, Fax: + 45 86121653; E-mail: