Effect Of The Intracorneal Ring Implant In Keratoconus: Efficacy, Safety And Stability
Published 2026 - 44th Congress of the ESCRS
Reference: POCOR332 | Type: Free paper | DOI: 10.82333/cvnx-xe84
Authors: Dr Sthefania Briceno Fernandez* 1 , Dr Angel E Barroso C 1 , Dr Monika Bohorquez 1 , Dr Jean C Moreno T 2
1cornea ,centro clinico san cristobal ,san cristobal ,Venezuela, Bolivarian Republic Of, 2anterior segment ,Hospital universitario de maracaibo,maracaibo ,Venezuela, Bolivarian Republic Of
Purpose
To evaluate the 16-month effects of the implantation of intrastromal corneal ring segments (ICRS) in keratoconus (KC) with manual surgical technique on tomography/topography and aberrometry parameters obtained with Pentacam AXL and their stability over time.
Setting
San Cristóbal University Hospital, San Cristóbal, Táchira, Venezuela.
Methods
A prospective,observational and experimental study was conducted to evaluate the clinical outcomes of Ferrara-type intracorneal ring segment surgery (ICRS) both symmetrical and asymmetrical depending on the keratoconus phenotype with manual surgical technique.The study included 32 eyes with a 16-month follow-up period.The variables analyzed included age,sex,phenotype and degree of keratoconus.Preoperative and postoperative evaluations included flat keratometry (K1), steep keratometry (K2), medium keratometry (KM),astigmatism,corneal asphericity, spherical aberration, and coma.The visual results were measured using uncorrected visual acuity (UCVA) and corrected distance visual acuity (CDVA).Data were analyzed using the paired Student t-test.
Results
The mean age was 23.34 years, with a male predominance (53%). The keratoconus "duck" phenotype was the most frequent (28.1%). The most frequent grade of keratoconus was II (34%). Significant flattening was observed: K1 decreased by 4 D, K2 by 3.5 D and KM by 5 D (p<0.05 for all). Astigmatism was reduced by 3.3 D (p<0.05). Postoperative findings included an average asphericity of 0.545 (p<0.05), a spherical aberration of 0.77 and a coma of 1.566, the decrease in coma was not statistically significant as there were grade IV keratoconus in the sample with coma values above 4. Postoperative UCVA improved to 0.5 logMAR (p<0.05). Safety and efficacy scores were 1.3 and 1.0, respectively.
Conclusions
The surgery of the intracorneal ring type Ferrara with manual technique seems to be a safe and effective treatment for the keratoconus, particularly for specific morphological patterns such as "duck" and "nipple". Both visual results and corneal parameters showed significant improvement, demonstrating the overall efficacy of the procedure for keratoconus treatment with excellent stability of results throughout the study. Its function as an artificial limb with greater structural support, together with a positive redistribution of stress, could be the cause of disease stabilization.