Posters
Femtosecond laser-assisted deep anterior lamellar keratoplasty, in keratoconus
Poster Details
First Author: L.Diamante BRAZIL
Co Author(s): Y. Moreira I. Castilhos A. Bottin F. Branco
Abstract Details
Purpose:
Keratoplasty has been performed as a definitive treatment for cases of advanced keratoconus with low vision, intolerance to the use of contact lens, and in the infeasibility of an Intrastromal ring implant. Penetrating Keratoplasty (PK) was the initial technique for these cases, however it presented a considerable rate of complications. Deep anterior lamellar keratoplasty (DALK) was introduced to decrease such complications by preserving the recipient's healthy cornea. In cases of cornea with superficial anterior lamellar opacities, there is the possibility of superficial anterior lamellar keratoplasty with Femtosecond technique, that optimize the technique by making the cut more precise and regular.
Setting:
This study was based on clinical ophthalmological examination, in addition to corneal tomography, and corneal topography ( galillei ) pré and post surgery. All of this, performed at the Hospital de Olhos do Paraná, Curitiba, Brazil.
Methods:
Male, 38 years old, with low visual acuity in both eyes, worse in the left eye (LE). Diagnosed keratoconus 18 years ago. Ophthalmic background: PRK + Crosslinking (Athens Protocol) in LE for 7 years. Visual acuity (VA) with correction in right eye 20/20, and in the left eye 20/60; Refraction RE-0.75 -0.50 172, and LE +3.75 -1.00 89. Biomicroscopy (LE): anterior stromal haze. Ultrasonic pachymetry: RE 505 microns, in LE 335 microns. And, Galilei in LE presented an asymmetrical area of corneal ectasia on the posterior face. Opted for FALK, with resection of 250um (epithelium + stroma), and diameter 8.2mm.
Results:
In the postoperative period, no inflammatory signs, no corneal ulcerations. After 50 days, corneal points were gradually removed according to the topography. After 10 months, the central planing worsened and failed to improve AV CC LE: 20/60 and RX: LE: +6.00 -1.00 75. That is, with the permanence of the central corneal planing , an increase in the residual degree was observed, +6.00 spherical diopters. And therefore, as a compensation mechanism, central epithelial growth, evidenced by the corneal tomography map after FALK. This also showed visualization of the post-surgical interface, with a reduction in the progressive receptor stroma from the periphery to the center of the cornea. While the donor coverslip has a constant thickness along its entire length. The new surgical approach is then chosen: DALK, since the patient has a history of poor contact lens adaptation. It evolves with an improvement in the central topographic pattern, without starting to remove points.
Conclusions:
The preparation of the donor and recipient button for anterior lamellar keratoplasty (ALK) can be performed manually, or with the use of excimer laser. However, possible irregularities in the stromal interface of the donor lamella and the recipient cornea can generate unsatisfactory visual results. At FALK, there is precision in the lamellar cut, with improvement in aspects of thickness, diameter and quality of the cut. Furthermore, optical aberrations are less important when compared to manual technique. Despite this, it is not harmless to failure. Therefore, a good preoperative evaluation with complex exams must be performed for a favorable treatment planning.
Financial Disclosure:
None
