Posters

Topography-guided PRK without cross-linking in keratoconus treatment

Poster Details

First Author: I.Pacheco Soares Carneiro PORTUGAL

Co Author(s):    J. Heitor   N. Silva   M. Neves   M. Gomes   L. Oliveira        

Abstract Details

Purpose:

PRK guided by corneal topography and associated with crosslinking has been increasingly used in the treatment of keratoconus, due to the high predictability of excimer laser ablation. However, the predictability of ablation is subsequently affected by the progressive aplanation of the cornea induced by crosslinking itself. The aim of this study was to evaluate the safety and stability of the topo guided PRK without the association of crosslinking in patients in whom, by age, the disease is already naturally stabilized.

Setting:

Centro Hospitalar Universitário do Porto, Porto, Portugal.

Methods:

5 eyes of 5 patients with keratoconus and older than 40 years of age, previously submitted to intracorneal ring segments but still presenting visual acuity not satisfactory due to corneal irregularity, were submitted to topo guided PRK without crosslinking. All patients were intolerant to contact lenses. Visual acuity and several parameters of corneal topography were evaluated preoperatively and at 1, 2, 6 and 12 months, to verify corneal stability. In all treatments an optical zone between 5.0 and 5.5mm was used to minimize the amount of tissue to be removed (maximum ablation of 50μm).

Results:

The mean variation between preoperative and postoperative values (second month after treatment) was: improvement of 0.28 in visual acuity without correction (mean 0.12 to 0.4), improvement of 0.37 in corrected visual acuity with glasses (mean 0.5 to 0.87), reduction in the mean K of -1.13D and in the maximum K of -1.0D. Significant regularization of the anterior surface of the cornea was verified in all cases, with stability of all corneal topography parameters at 12 months of follow-up.

Conclusions:

The use of topo guided PRK without crosslinking seems to be a safe option in the medium term in patients with keratoconus at ages in which the natural crosslinking of the cornea has already occurred. Longer follow-up and larger numbers of patients will be required to verify the results and safety of this technique in the long term.

Financial Disclosure:

None