Abstract
Purpose: :
To evaluate the safety, efficacy and stability of intrastromal rings segments (one or two segments drawing a circle of 5 mm diameter, in each eye depending of the case) for the treatment of ectatic disorders of the cornea, in terms of visual outcome, restoration of contact lens tolerance and intraoperative and posteoperative complicactions.
Methods: :
Prospective data were collected from 67 ectatic corneas of 61 patients (38 men and 23 women). Sixty keratoconic corneas, 7 post-lasik ectasia, and 4 marginal pellucid degeneration. All patients were contact lens intolerant. The uncorrected and best corrected visual acuity, topographic profiles, pachymetry, slit lamp examination were taken preoperatively and 1 week, 3 months, 1 year, 18 months and two years after surgery.
Results: :
At two years, the uncorrected and best corrected visual acuity inproved in 82.8% and 75.35% of eyes, respectively (p <0.001). The results were relatively stable throughout follow-up period. The proportion of eyes with a best corrected visual acuity ≥ 0.5 increased from 27% preoperatively, to 51% at one year and 59% at two years(p <0.001). Ninety-four eyes gained one line of vision or more, white 25 of them gained 5 lines or more at 2 years of follow-up. Mean keratometry values decreased from 50,01 ± 2.43 diopters preoperatively to 46.17 ± 2.44 at 18 moths and 45.95 ± 3.23 at 2 years (p <0.001). Intracorneal rings were removed in three cases without complicactions.
Conclusions: :
Intracorneal rings implantation was a safe and efficacious treatment for corneal ectasia. Significant improvements in objective visual outcomes were achieved in most of cases, with restoration on contact lens tolerance.
Keywords: cornea: clinical science • keratoconus • refractive surgery