International Journal of Keratoconus and Ectatic Corneal Diseases

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VOLUME 6 , ISSUE 2 ( July-December, 2017 ) > List of Articles


Intrastromal Corneal Ring Segments in Children with Keratoconus

Paulo Ferrara, Leonardo Torquetti, Guilherme Ferrara

Citation Information : Ferrara P, Torquetti L, Ferrara G. Intrastromal Corneal Ring Segments in Children with Keratoconus. Int J Kerat Ect Cor Dis 2017; 6 (2):45-48.

DOI: 10.5005/jp-journals-10025-1142

License: CC BY 3.0

Published Online: 01-09-2017

Copyright Statement:  Copyright © 2017; The Author(s).



To evaluate the long-term follow-up of Ferrara intrastromal corneal ring segments (ICRSs) (Ferrara Ophthalmics, Belo Horizonte, Brazil) implantation for the management of keratoconus in children.

Study design

Paulo Ferrara Eye Clinic, Belo Horizonte, Minas Gerais, Brazil.

Materials and methods

A total of 58 eyes of 37 children with keratoconus were included. One or two ring segments were inserted into the cornea, embracing the keratoconus area. Statistical analysis included preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), asphericity, pachymetry, and keratometry.


Ferrara ICRS implantation significantly improved the mean UDVA and CDVA. Corneal tomography (Pentacam®) showed corneal flattening in all eyes implanted with the Ferrara ring. The mean K decreased, and the corneal asphericity and pachymetry increased in all cases.


The Ferrara ICRS improved all parameters after 2 years of implantation in children with keratoconus. There was significant corneal flattening after ring implantation with improvement of the UDVA and the CDVA. All studied parameters remained stable over time.

How to cite this article

Ferrara G, Ferrara P, Torquetti L. Intrastromal Corneal Ring Segments in Children with Keratoconus. Int J Kerat Ect Cor Dis 2017;6(2):45-48.

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