Intrastromal corneal ring segments implantation for post-LASIK ectasia: clinical, topographic and safety outcomes
First Author: C.Pinto PORTUGAL
Co Author(s): T. Monteiro N. Franqueira F. Faria-Correia R. Freitas J. Mendes
Corneal ectasia is a serious complication of laser-assisted in situ keratomileusis (LASIK), especially reported after extensive excimer laser ablations. In consequence, it can cause a devastating visual impairment as result of significant increase in ocular aberrations. We conducted this study to evaluate the visual, refractive, topographic and safety outcomes after implantation of intrastromal corneal ring segments (ICRS) for the management of patients with post-LASIK corneal ectasia.
Department of Ophthalmology, Hospital de Braga, Braga, Portugal.
This retrospective case series included 13 eyes of 11 consecutive patients with post-LASIK corneal ectasia submitted to Ferrara Ring (Ferrara Ophthalmics, Belo Horizonte, Brazil) ICRS implantation that completed a period of 12-month postoperative follow-up. ICRS were inserted in the corneal stroma after manual surgery. Variables evaluated included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, keratometric readings and coma. All parameters were accessed preoperatively and at 12 months postoperatively. Topographic evaluation was performed using Scheimpflug topography Pentacam (Oculus Optikgerate, Wetzlar, Germany).
Mean UDVA and CDVA improved significantly from 0,88±0,95 and 0,52±0,73 preoperatively to 0,43±0,60 and 0,23±0,55 logMAR postoperatively. One eye gained 1 line of CDVA and 9 eyes gained 2 or more. We found no cases of CDVA loss. Manifest sphere showed a non-significant decrease. Manifest cylinder and spherical equivalent decreased significantly from -3,83±1,84 and -3,54±2,56 to -2,02±0,90 and -2,39±2,36 D during the 12-month follow-up, respectively. Mean achieved reduction of spherical equivalent was 1,16±1,51 D. Mean values of K1 and K2 reduced significantly. Coma reduced significantly from 2,26±1,10 to 1,18±0,89. We observed no cases of ICRS extrusion, endothelial perforation or explantation.
In our series, ICRS implantation revealed to be an effective and safe surgical option for the management of post-LASIK ectasia. In this case series, we showed its ability to restore visual acuity and to control the progression of keratectasia by improving refractive and topographic parameters.