Collagen cross-linking effect on progressive keratoconus in patients younger than 18 years of age: A clinical trial

Authors
Alireza Peyman 1
Ali Kamali 1
Maral Khushabi 1
Kobra Nasrollahi 1
Neda Kargar 1
Maryam Taghaodi 1
Hasan Razmjoo 1
Farhad Fazel 1
Asiyeh Salesi 2
1 Department of Ophthalmology, Isfahan University of Medical Sciences, Isfahan, Iran
2 Department of Statistics, Allameh Tabatabai University, Tehran, Iran
Abstract
Background: Keratoconus is a bilateral non-inflammatory corneal disease. Collagen cross-linking (CXL) is a new treatment option for the disease that uses ultraviolet A light irradiation and riboflavin administration. The aim of this study is to evaluate the effect of CXL on corneal topographic and refractive values in patients with keratoconus younger than 18 years of age.
Materials and Methods: For the clinical trial study, 37 patients (64 eyes) younger than 18 years of age with progressive keratoconus were included. Age, sex, family history of keratoconus, and history of allergic disorders and eye rubbing were recorded. Refractive, topographic, and topometric indices were evaluated before and 12 months after the CXL with 3mW for 30 minutes.
Results: Mean age (±SD) of the patients was 15.83 ± 1.53 years; 26 (70.3%) of the 37 patients were male. Fourteen (37.8%) had positive family history of keratoconus, 11 (29.7%) had history of allergic disorders, and 15 (40.5%) had positive history of eye rubbing. Of the refractive values, cylinder value decreased significantly from −4.50 ± 0.29 to −4.11 ± 0.28 (P = 0.001). Also, the logarithm of minimal angle of resolution (logMAR) uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) improved significantly 12 months after CXL (P = 0.012 and 0.001, respectively). Maximum keratometry before and after the operation was 53.82 ± 0.72 and 53.33 ± 0.72, respectively (P = 0.018). Differences for simulated K values, the thinnest cornea pachymetry, keratoconus index (KI), index of highest asymmetry (IHA), and index of highest decentration (IHD) before and 12 months after the CXL were statistically significant (P = 0.015, 0.034, <0.001, 0.017, 0.019, and 0.004, respectively).
Conclusion: CXL improves the refractory, topographic, and topometric indices in patients with keratoconus younger than 18 years of age.

Keywords

1.
Rabinowitz YS, Keratoconus. Surv Ophthalmol 1998;42:297-319.  Back to cited text no. 1
    
2.
Kim H, Joo CK. Measure of keratoconus progression using Orbscan II. J Refract Surg 2008;24:600-5.  Back to cited text no. 2
    
3.
Bechrakis N, Blom ML, Stark WJ, Green WR. Recurrent keratoconus. Cornea 1994;13:73-7.  Back to cited text no. 3
    
4.
Pantanelli S, MacRae S, Jeong TM, Yoon G. Characterizing the wave aberration in eyes with keratoconus or penetrating keratoplasty using a high-dynamic range wavefront sensor. Ophthalmology 2007;114:2013-21.  Back to cited text no. 4
    
5.
Krachmer JH, Feder RS, Belin MW. Keratoconus and related noninflammatory corneal thinning disorders. Surv Ophthalmol 1984;28:293-322.  Back to cited text no. 5
    
6.
Tuft SJ, Moodaley LC, Gregory WM, Davison CR, Buckley RJ. Prognostic factors for the progression of keratoconus. Ophthalmology 1994;101:439-47.  Back to cited text no. 6
    
7.
Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol 2003;135:620-7.  Back to cited text no. 7
    
8.
Arbelaez MC, Sekito MB, Vidal C, Choudhury SR. Collagen cross-linking with riboflavin and ultraviolet-A light in keratoconus: One-year results. Oman J Ophthalmol 2009;2:33-8.  Back to cited text no. 8
[PUBMED]  Medknow Journal  
9.
Kohlhaas M, Spoerl E, Schilde T, Unger G, Wittig C, Pillunat LE. Biomechanical evidence of the distribution of cross-links in corneastreated with riboflavin and ultraviolet A light. J Cataract Refract Surg 2006;32:279-83.  Back to cited text no. 9
    
10.
Razmjoo H, Nasrollahi AP, Salam H, Karbasi N, Najarzadegan MR. Topographic corneal changes after collagen cross-linking in patients with corneal keratoconus. J Res Med Sci 2013;18:882-6.  Back to cited text no. 10
[PUBMED]  Medknow Journal  
11.
Suzuki M, Amano S, Honda N, Usui T, Yamagami S, Oshika T. Longitudinal changes in corneal irregular astigmatism and visual acuity in eyes with keratoconus. Jpn J Ophthalmol 2007;51:265-9.  Back to cited text no. 11
    
12.
Saini JS, Saroha V, Singh P, Sukhija JS, Jain AK. Keratoconus in Asian eyes at a tertiary eye care facility. Clin Exp Optom 2004;87:97-101.  Back to cited text no. 12
    
13.
Zadnik K, Barr JT, Edrington TB, Everett DF, Jameson M, McMahon TT, et al. Baseline findings in the collaborative longitudinal evaluation of keratoconus (CLEK) study. Invest Ophthalmol Vis Sci 1998;39:2537-46.  Back to cited text no. 13
    
14.
Gonzalez V, McDonnell PJ. Computer-assisted corneal topography in parents of patients with keratoconus. Arch Ophthalmol 1992;110:1413-4.  Back to cited text no. 14
    
15.
Davies PD, Lobascher D, Menon JA, Rahi AH, Ruben M. Immunological studies in keratoconus. Trans Ophthalmol Soc U K 1976;96:173-8.  Back to cited text no. 15
    
16.
Rahi A, Davies P, Ruben M, Lobascher D, Menon J. Keratoconus and coexisting atopic disease. Br J Ophthalmol 1977;61:761-4.  Back to cited text no. 16
    
17.
Copeman PW. Eczema and keratoconus. Br Med J 1965;2:977-9.  Back to cited text no. 17
    
18.
Karseras AG, Ruben M. Aetiology of keratoconus. Br J Ophthalmol 1976;60:522-5.  Back to cited text no. 18
    
19.
Saffarian L, Khakshoor H, Zarei-Ghanavati M, Esmaily H. Corneal crosslinking for keratoconus in iranian patients: Outcomes at 1 year following treatment. Middle East Afr J Ophthalmol 2010;17:365-8.  Back to cited text no. 19
[PUBMED]  Medknow Journal  
20.
Raiskup-Wolf F, Hoyer A, Spoerl E, Pillunat LE. Collagen crosslinking with riboflavin and ultraviolet-A light in keratoconus: Long-term results. J Cataract Refract Surg 2008;34:796-801.  Back to cited text no. 20
    
21.
Hoyer A, Raiskup-Wolf F, Spörl E, Pillunat LE. Collagen cross-linking with riboflavin and UVA light in keratoconus. Results from Dresden. Ophthalmologe 2009;106:133-40.  Back to cited text no. 21
    
22.
Agrawal VB. Corneal collagen cross-linking with riboflavin and ultraviolet - A light for keratoconus: Results in Indian eyes. Indian J Ophthalmol 2009;57:111-4.  Back to cited text no. 22
[PUBMED]  Medknow Journal  
23.
Wittig-Silva C, Whiting M, Lamoureux E, Lindsay RG, Sullivan LJ, Snibson GR. A randomized controlled trial of corneal collagen cross-linking in progressive keratoconus: Preliminary results. J Refract Surg 2008;24:S720-5.  Back to cited text no. 23
    
24.
Caporossi A, Mazzotta C, Baiocchi S, Caporossi T. Long-term results of riboflavin ultraviolet a corneal collagen cross-linking for keratoconus in Italy: The Siena eye cross study. Am J Ophthalmol 2010;149:585-93.  Back to cited text no. 24
    
25.
Wollensak G, Spörl E, Seiler T. Treatment of keratoconus by collagen cross linking. Ophthalmologe 2003;100:44-9.  Back to cited text no. 25
    
26.
Snibson GR. Collagen cross-linking: A new treatment paradigm in corneal disease - A review. Clin Experiment Ophthalmol 2010;38:141-53.  Back to cited text no. 26
Advanced Biomedical Research
Volume 2015, November
November 2015
Pages 1-5