International Journal of Keratoconus and Ectatic Corneal Diseases

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VOLUME 3 , ISSUE 3 ( September-December, 2014 ) > List of Articles


Intrastromal Corneal Ring Segments Implantation in Patients with Mild Keratoconus

Pablo F Rodrigues, Wagner G Dias

Citation Information : Rodrigues PF, Dias WG. Intrastromal Corneal Ring Segments Implantation in Patients with Mild Keratoconus. Int J Kerat Ect Cor Dis 2014; 3 (3):122-126.

DOI: 10.5005/jp-journals-10025-1091

Published Online: 01-06-2017

Copyright Statement:  Copyright © 2014; The Author(s).



The purpose of this study is to evaluate the topographic, topometric and visual changes after implantation of Ferrara intrastromal corneal ring segments (ICRS) in grades I and II keratoconus patients.

Materials and methods

The chart records of 50 consecutively operated keratoconus patients were reviewed. The patients were operated on by the same surgeon, with the manual technique. All patients were preoperatively and postoperatively evaluated with the Pentacam (OCULUS Optikgeräte, Wetzlar, Germany). The studied parameters were: uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), keratometry, corneal asphericity and corneal volume.


Fifty eyes of 42 patients (26 males and 16 females) were analyzed. The mean preoperative UDVA was 0.91 ranging from LogMAR 0.10 to 1.30. The mean postoperative CDVA was 0.19 ranging from 0.00 to 0.54 LogMAR. The postoperative CDVA was equal or better than 0.18 in 37 cases (74%). The mean K1 decreased from 45.80D (±2.52) preoperatively to 44.27D (± 2.10) postoperatively and the mean K2 value, from 49.06D (± 2.09) to 46.22D (±1.89). The mean asphericity increased from −0.71 preoperatively to −0.29 postoperatively. The average preoperative corneal volume was 56.89 ± 3.11 mm3 while the average postoperative corneal volume was 57.64 ± 3.05 mm3.


The study supports the early indication of implantation of Ferrara ICRS in mild to moderate keratoconus cases in order to achieve good visual, keratometric and ashpericity outcomes.

How to cite this article

Rodrigues PF, Ferrara G, Ferrara P, Dias WG, Torquetti L. Intrastromal Corneal Ring Segments Implantation in Patients with Mild Keratoconus. Int J Kerat Ect Cor Dis 2014;3(3):122-126.

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