A novel inverse finite element approach to analyze corneal deformation after SMILE and LASIK
Session Details
Session Title: Moderated Poster Session: News on Cornea
Venue: Poster Village: Pod 1
First Author: : T.Grover INDIA
Co Author(s): : R. Shetty A. Sinha M. Francis P. Khamar
Abstract Details
Purpose:
Current evidence of biomechanical changes after small incision lenticule extraction(SMILE) and femtosecond laser-assisted in-situ keratomileusis(FS-LASIK) have been debatable. This study aims to analyze the acute biomechanical changes associated with SMILE and FS-LASIK using a novel inverse finite element model(IFEM)
Setting:
Narayana Nethralaya Postgraduate Eye Institute and Superspeciality Hospital, Bangalore, India
Methods:
A total of 18 patients were recruited with similar bilateral refraction. The patients underwent SMILE in one eye and FS-LASIK in the other eye. After detailed clinical examination, patients underwent imaging on Pentacam HR and Corvis-ST before and after surgery (1, 3 and 6month). Corneal tomography from Pentacam-HR was used to construct 3-D corneal model and mesh.The I-FEM derived the best fit material properties to describe the corneal deformation measured by Corvis-ST.Using the computed properties, stress strain analogue for each measurement was formulated by simulating intraocular pressure(IOP; 0-60mmHg).The displacement of the corneal apex was calculated from stress-strain analogue
Results:
At an IOP=30mmHg, displacement of the corneal apex was noted. In LASIK eyes, the displacement increased acutely at 1 month followed by continued remodelling(-9.3%) up to 3 months. However, there was slight recovery of corneal biomechanical strength up to 6 month(+12.8%). In SMILE, corneal displacement remained the same at 1 and 3 month indicating biomechanical stability. Up to 6 months, there was significant recovery such that corneal displacement was less(+27.8%). Similar trends were observed at all other IOPs
Conclusions:
SMILE showed more biomechanical stability and improved recovery of biomechanical strength than LASIK
Financial Disclosure:
NONE