Long-term efficacy and safety of topography-guided irregular astigmatism treatment after corneal transplantation: can we predict it?

Session Details

Session Title: Surgical Cornea: Keratoplasty & Corneal Grafts

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

Paper Time: 15:36

Venue: Room A3, Podium 3

First Author: : M.Oliveira PORTUGAL

Co Author(s): :    T. Rodrigues   A. Rosa   J. Gil   E. Costa   M. Quadrado   J. Murta     

Abstract Details

Purpose:

Penetrating keratoplasty (PK) is one of the most commonly performed transplant procedures worldwide. Although it is generally successful, patients frequently present with high irregular postoperative astigmatism. Topography-guided photorefractive keratectomy (TG-PRK) can be used to treat post-PK irregular astigmatism Here, we aimed to analyze the long-term efficacy and safety of TG-PRK after PK, as well as to identify predictive factors of response

Setting:

Department of Ophthalmology, Centro Hospitalar e Universitário de Coimbra (CHUC)

Methods:

Case series. Eyes with irregular astigmatism after PK treated with TG-PRK (Allegretto Wave Eye-Q) with the customized ablation treatment protocol were included. All treatments had been planned to correct the topographic irregularities, as well as to reduce the refractive error after neutralizing the induced refractive change. Clinical records and the treatment plan were reviewed and the following data was collected: baseline disease; time between PK and TG-PRK; best-corrected visual acuity (BCVA); manifest refraction and topographic parameters. Paired t-tests were used to compare pre- and post-PRK outcomes. Univariate regression linear models were used to assess baseline factors as predictors of response.

Results:

We included 43 eyes, from 40 patients. At the last postoperative follow-up (mean 22.9 ± 13.5 months), we observed a significant improvement in the refractive parameters (cylinder P<0.001; sphere P<0.001; spherical equivalent P=0.003), although cylinder increased from the 3rd to last visit (P=0.03).Topographic parameters also improved (K2 P<0.001; Kmax P=0.005). When dividing the sample into two groups considering those who did not improve BCVA versus the remaining ones, there was not a statistically significant difference between the two groups concerning baseline BCVA (P=0.567); spherical equivalent (P=0.959); cylinder (P=0.323); sphere (P=0.815); time between PK and TG-PRK or baseline topography.

Conclusions:

This is one of the largest case series of TG-PRK to treat irregular astigmatism in postcorneal transplantation eyes. Our results confirm that TG-PRK is an efficient treatment, associated with significant improvements of both refractive and topographic parameters. The regression in the cylinder may mean that it is necessary to hypercorrect this parameter in the treatment plan. Baseline BCVA, refractive and topographic parameters are not predictors of the visual outcome.

Financial Disclosure:

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