International Journal of Keratoconus and Ectatic Corneal Diseases

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VOLUME 2 , ISSUE 1 ( January-April, 2013 ) > List of Articles


Outcomes of Corneal Collagen Cross-linking for Keratoconus the Effect of Cone Location

Vinay Agrawal

Citation Information : Agrawal V. Outcomes of Corneal Collagen Cross-linking for Keratoconus the Effect of Cone Location. Int J Kerat Ect Cor Dis 2013; 2 (1):16-19.

DOI: 10.5005/jp-journals-10025-1042

Published Online: 00-04-2013

Copyright Statement:  Copyright © 2013; Jaypee Brothers Medical Publishers (P) Ltd.



One-year outcome of corneal collagen cross-linking (CXL) for keratoconus with reference to topographic cone location.

Materials and methods

Clinical audit of the results of CXL were used. Three hundred and seventy-eight eyes of 225 patients with preoperative and 12-month completed follow-up were included. Cone location was defined by cone location magnitude index (CLMI) using the Keratron scout topography system. The eyes were divided into two groups–central with cone location within 3 mm zone of the topography map and paracentral with cone location between the 3 and 5 mm zones.


The overall group showed a mean flattening of the CLMI of 1.67 D [preoperative 53.35 ± 5.63 D, 12 months 51.69 ± 4.67 (p = 0.095)]. The flattening in central cone group was 2.67 D [preoperative 54.01 ± 5.3819, at 12 months to 51.341 ± 4.588 (p = 0.016)]. In paracentral cone group the flattening was lesser at 1.73 D [preoperative apex K 52.805 ± 6.382, at 12 months 51.03 ± 4.82 (p = 0.006)]. The difference between groups was statistically significant (p < 0.001). The central cone group showed no significant shift in cone position [preoperative 1.0059 ± 0.24, at 12 months 0.986 ± 0.206 (p = 0.45)]. The paracentral cone group showed a significant mean shift of 1.05 mm in cone location [preoperative 2.224 ± 0.440, at 12 months 1.196 ± 0.529 (p = 0.001)].


Cone location has an impact on the results of corneal cross-linking. The paracentral cones show a significant shift toward the center of the cornea and the central cones show a larger flattening.

How to cite this article

Agrawal V. Outcomes of Corneal Collagen Cross-linking for Keratoconus the Effect of Cone Location. Int J Kerat Ect Cor Dis 2013;2(1):16-19.

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