Posters

Keratoconus management with partial topography-guided PRK combined with high-fluence CXL (Athens protocol): comparative analysis according to phenotype classification

Poster Details

First Author: R.Pinheiro PORTUGAL

Co Author(s):    J. Gil   A. Silva   A. Rosa   M. Quadrado   C. Tavares   J. Neto-Murta     

Abstract Details

Purpose:

To evaluate how preoperative topographic characteristics of keratoconic eyes impact on the results obtained with simultaneous topography-guided photorefractive keratectomy (PRK) followed by corneal collagen cross- linking (CXL) for the treatment of keratoconus.

Setting:

Single-center, retrospective clinical study.

Methods:

Patients diagnosed with keratoconus underwent simultaneous, same-day, partial topography-guided photorefractive keratectomy (t-PRK) and corneal collagen cross-linking (CXL). The best spectacle corrected visual acuity (BSCVA), refractive correction and corneal topography were reviewed. Outcomes were analysed based on the patients’ preoperative morphologic characteristics. Keratoconus cases were classified as central, paracentral or pericentral according to the location of the thinnest point on the corneal pachymetry map. Cases were also classified as coincident or non-coincident when the differences between the axis of refractive cylinder and corneal flattest meridian were inferior or superior to 30 degrees.

Results:

We included 91 eyes, mean aged 33.36±12.43 years. Mean follow-up was 13±80 months. Mean BSCVA improved from 0.44±0.25 to 0.27±0.28 logMAR(P<0.01). This improvement was more noted in the central(0.43±0.24 to 0.24±0.15),followed by paracentral(0.46±0.25 to 0.36±0.27)and pericentral cases(0.27±0.12 to0.20). Visual gain was not significantly different comparing coincident or non-coincident cases. Improvement in flat and steep keratometry was also better in central than paracentral or pericentral cones, although the difference was significant for flat only(p=0.05). Reduction in flat and steep keratometry was not significantly different comparing coincident and non-coincident cases (p=0.31 both).

Conclusions:

Combined simultaneous topo-guided PRK and CXL appears to be an effective option in the treatment of patients with keratoconus. Cases presenting with central cones appear to have better results. Discordance between the topographical and refractive axis do not seem to impact on the results of the surgery.

Financial Disclosure:

None