A Study on Visual Outcome of Patients with Keratoconus after Corneal Collagen Crosslinking

Ballga Barzan  Ahmed; Tara Mahmood  Hassan; Bakhtiar Qadir  Hamasalih

doi:10.56056/amj.2025.321

Authors

Ballga Barzan Ahmed MBChB, HD Ophthalmology, trainee of Kurdistan higher council of medical specialties, Sulaimaniyah, Iraq
Tara Mahmood Hassan MBChB, SMSB, Assistant Professor in Ophthalmology, Sulaimaniyah, Iraq
Bakhtiar Qadir Hamasalih MBChB, SMSB, Assistant Professor in Ophthalmology, Sulaimaniyah, Iraq

DOI:

https://doi.org/10.56056/amj.2025.321

Keywords:

Cross-linking, Keratoconus, Pentacam topography

Abstract

Background and objectives: Cross-linking of the corneal collagen is regarded as a new treatment technique for a non-inflammatory thinning disease of the cornea-known as keratoconus, to strengthen the biomechanical elements of the cornea. Riboflavin (Vit.B2) and UV-A light have been shown to be effective at stopping progression of keratoconus.

Aim: to evaluate the effects of collagen cross-linking in patients with keratoconus.

Methods: A retrospective, non-controlled study was performed on forty-five patients (64 eyes) with keratoconus in whom collagen crosslinking was done between years (2017-2021). It was conducted in Bright Eye, Tooe Maleek, and the Eye Center private hospitals in sulaimaniya city. We measured the distance visual acuity with and without glasses (Snellen acuity chart and decimal notation), the, the spherical equivalent and cylindrical refractive error (autorefractometer), the central corneal thickness and the mean keratometic reading (corneal topography). These were taken before and after crosslinking in a period between 6-12 months, and then t-test was used to compare and analyze the results.

Results: After comparing the pre- and post-crosslinking findings, we found an improvement in the uncorrected VA (by 0.06±0.04) and best corrected VA (by 0.10±0.03). The central corneal thickness was decreased by a mean of (13±12µm) and the mean keratometric reading decreased by a mean of (0.9D). However, each of the spherical equivalent and cylindrical refractive errors showed no significant difference before and after the procedure (stabilized).

Conclusion: The procedure (collagen crosslinking) was efficacious in stopping progression of the disease.

Downloads

Download data is not yet available.

References

Li X, Rabinowitz YS, Rasheed K, Yang H. Longitudinal study of the normal eyes in unilateral keratoconus patients. Ophthalmology. 2004; 111: 440-6.

Hwang S, Lim DH, Chung TY. Prevalence and Incidence of Keratoconus in South Korea: A Nationwide Population-based Study. Am J Ophthalmol. 2018; 192:56-64.

Santodomingo-Rubido J, Carracedo G, Suzaki A, Villa-Collar C, Vincent SJ, Wolffsohn JS. Keratoconus: An updated review. Cont Lens Anterior Eye. 2022; 45(3):101559.

Martínez-Abad A, Pinero DP. New perspectives on the detection and progression of keratoconus. Journal of Cataract & Refractive Surgery. 2017; 1;43(9):1213-27.

Kanclerz P, Khoramnia R, Wang X. Current developments in corneal topography and tomography. Diagnostics. 2021; 13;11(8):1466.

Barbara A. Textbook on Keratoconus: New Insights, First edition, India. Jitendar P Vij. 2012, 111–12.

Gregory L, Louis B. American Academy of Ophthalmology, BCSC. Section 13, refractive surgery. 2020-2021; 7: 131-2.

Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol. 2003; 135:620–7.

Uysal BS, Sarac O, Yaman D, Akcay E, Cagil N. Optical performance of the cornea one year following keratoconus treatment with corneal collagen cross-linking. Curr Eye Res. 2018; 43:1415–21.

Badawi AE, Abou Samra WA, El Ghafar AA. Predictive factors of the standard cross-linking outcomes in adult keratoconus: One-year follow-up. J Ophthalmol. 2017:4109208.

Lamy R, Netto CF, Reis RG, Procopio B, Porco TC, Stewart JM et al., Effects of corneal cross-linking on contrast sensitivity, visual acuity and corneal topography in patients with keratoconus. Cornea. 2013; 32(5):591-6.

Hashemi H, Seyedian MA, Miraftab M, Fotouhi A, Asgari S. Corneal Collagen cross-linking with riboflavin and ultraviolet irradiation for keratoconus: long-term results. Ophthalmology. 2013; 120(8):1515-20.

Iqbal M, Elmassry A, Badawi AE, Gharieb HM, Said OM. Visual and Refractive Long-Term Outcomes Following Standard Crosslinking in Progressive Keratoconus Management. Clinical Ophthalmology. 2019; 2477-11.

Derakhshan A, Shandiz JH, Ahadi M, Daneshvar R, Esmaily H. Short term outcomes of collagen crosslinking for early keratoconus. J Ophthalmic Vis Res. 2011; 6:155–9.

Sedaghat M, Baqheri M, Ghavami S, Bamdad S. Changes in corneal topography and biomechanical properties after collagen cross-Linking for Keratoconus: 1-year results. Middle East Afr J Ophthalmol. 2015; 22(2):212-9.

Saffarian L, Khakshoor H, Zarei GM, and Esmaily H. Corneal Crosslinking for Keratoconus in Iranian Patients: Outcomes 1 Year following treatment. Middle East Afr J Ophthalmol 2010; 17(4):365-8.

Aixinjueluo W, Usui T, Miyai T, Toyono T, Sakisaka T, Yamagami S. Accelerated transepithelial corneal cross-linking for progressive keratoconus: A prospective study of 12 months. Br J Ophthalmol. 2017; 101:1244–9.

Grewal DS, Brar GS, Jain R, Sood V, Singla M, Grewal SP. Corneal collagen crosslinking using riboflavin and ultraviolet-A light for keratoconus: one-year analysis using Scheimpflug imaging. J Cataract Refract Surg. 2009; 35(3):425-32.