Posters

Comparative analysis of total ocular aberrations and posterior corneal surface metrics following ultra-thin manual Descemet's stripping endothelial keratoplasty (UTMDSEK): a pilot study

Poster Details

First Author: T.Ahmed UK

Co Author(s):    A. Konstantopoulos   M. Rashid   A. Luff   N. Attridge   P. Hossain   D. Anderson

Abstract Details

Purpose:

To compare the profile of total ocular aberrations measured by ray tracing and Shack Hartmann aberrometers with posterior surface topographic changes using Scheimpflug imaging and anterior segment optical coherence tomography (AS-OCT) following UTMDSEK in pesudophakic patients.

Setting:

University Hospital Southampton NHS Foundation Trust and Optegra Solent Hospital, Hampshire, UK

Methods:

Retrospective, non-consecutive case series. Fourteen eyes of 11 pseudophakic patients who had undergone routine UTMDSEK for corneal decompensation secondary to Fuchs' Dystrophy. Unaided and best corrected vision, refraction and keratometry were measured. Aberrometry using a ray tracing aberrometer (Tracey Technologies, Houston, USA) and a Shack Hartmann device (Topcon KRW1, NJ, USA) was performed. Scheimpflug imaging using the Pentacam HR (Oculus Inc, Wetzlar, Germany) and AS-OCT using the Visante Omni (Carl Zeiss Meditec, CA, USA) were recorded. Aberration data was analysed with a multivariate multiple regression analysis with 10 continuous dependant variables (RMS, LO, HO, defocus, astigmatism, secondary astigmatism, coma, spherical, trefoil and total aberration) and three continuous independent variables (sagittal curvature, KPD and true net power).

Results:

The mean preoperative BCVA was 0.50±0.18 logMAR monocularly. The average endothelial graft thickness was 116μm±58.0 and the average total corneal thickness was 611μm±77.1 at last follow up. Mean follow up was 27.08 months, range (8-46 months). The mean preoperative MRSE was +0.81 D±3.03. At last follow up, the mean postoperative MRSE was -0.15 D±1.32 and the mean postoperative BCVA was 0.23±0.15 logMAR monocularly. We report HOA data up to 4th order using two different methods of measuring total ocular aberrations and posterior corneal surface topography using Scheimpflug imaging.

Conclusions:

We have previously reported UTMDSEK as a novel technique to safely and consistently dissect thin donor lenticules with mean graft thickness of < 100 micron one month following surgery in patients undergoing DSEK. We now describe the ocular aberrations of a small series of these patients using different wavefront sensing devices and compare these data with elevation data obtained using Scheimplug imaging and AS-OCT. FINANCIAL INTEREST: NONE