Unmasking the differential wound healing of anterior corneal and Bowman's surface after wavefront-guided LASIK

Session Details

Session Title: LASIK I

Session Date/Time: Sunday 23/09/2018 | 14:00-16:00

Paper Time: 14:58

Venue: Room A3, Podium 2

First Author: : H.Matalia INDIA

Co Author(s): :    N. C   A. Garg   U. Choudhary   R. Chandapura   A. Sinha Roy        

Abstract Details

Purpose:

To compare the curvature and aberrations of the anterior corneal and Bowman's surface after wavefront-guided (WFG) LASIK from low to high myopia

Setting:

Narayana Nethralaya Eye Hospital, Bangalore, India

Methods:

Twenty-two eyes underwent myopic WFG LASIK (Abbott Medical Optics or AMO, USA). Surgical planning was performed with the iDesign Advanced WaveScan aberrometer (AMO). Anterior segment optical coherence tomography (OCT) was performed with 1050 nm swept source OCT. A custom algorithm was developed to generate anterior corneal (A-E) and Bowman surface (E-B) topography and corneal wavefront aberrations (WF). Further, 3-D epithelium thickness map was analyzed with Zernike polynomials to map the asymmetry of thickness distribution. Epithelium distortion index (EDI) was defined from Zernike analyses (order = 6, analyses size = 6 mm).

Results:

Spherical and cylindrical error reduced from -4.63D to 0D and from -0.75D to 0.0D, respectively (p<0.0001). Steep and flat keratometry of A-E reduced by 3.8D and 6D, respectively (p<0.0001). Steep and flat keratometry of E-B reduced by 3.7D and 5.8D, respectively (p<0.0001). Spherical aberration of A-E increased by 0.03 µm (p=0.39) and E-B decreased by 0.21 µm (p=0.002). Vertical coma increase was same on both surfaces (0.26µm, p=0.78). RMS of higher order aberrations of A-E and E-B increased by 0.63 µm (p=0.02) and 1.04 µm (p=0.001), respectively. EDI increased from 1.03 to 1.61 µm (p=0.005).

Conclusions:

This is the first study to delineate wound healing of refractive interfaces within the cornea. EDI described a quantitative change in epithelium thickness distribution, which linked to greater WF at the Bowman's surface. These novel findings could be used for predictive modeling of curvature and WF changes after WFG LASIK and other procedures.

Financial Disclosure:

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