Abida Fida, Sadia Humayun, Iram Fatima, Imran Basit, Mazhar Ishaq, Fida Hussain


Background: This study was conducted to evaluate the safety of accelerated corneal collagen crosslinking (CXL) in keratoconus patients on basis of endothelial cell density measurements. Methods: We studied 24 patients (42 eyes) with diagnosed keratoconus who underwent accelerated CXL with 9 Mw/cm2 UVA irradiance for 10minutes. All patients underwent detailed examination and video keratography (VKG) for classification and confirmation of keratoconus. Patients with central corneal thickness (CCT) of ≥400µ were included in the study. Specular microscopy was done to note endothelial cell density (ECD) preoperatively and then at the end of 1st, 4th and 12th weeks’ post-operative period. Results: The study included 24 patients (42 eyes) from October 2016 to June 2017.  Among these 13 were females and 11 males with mean age of 20.15±6.73 years. Eighteen patients underwent the procedure in both eyes while 6 had the procedure in one eye. The pre-operative ECD mean±SD of right eye was 2743.97±542.77/mm2 and left eye was 2763.35±532.57/mm2. The post-operative ECD mean±SD of right and left eyes at the end of 12th post-op weak were 2806.34±520.11/mm2 and 2823.30±628.57/mm2 respectively. The pre and post-op ECD comparison showed p-values at first week post-op are 0.474 and 0.683 for right and left eyes respectively. Similarly, the p-values at 4th and 12 weeks post-op for right eye are 0.266 and 0.280 respectively. The p-values at 4th and 12th weeks for left eye are 0.913 and 0.404 respectively. Conclusion: Accelerated CXL protocols is safe and effective procedure and did not lead to significant change in ECD in our study population in three months post-procedural follow up. However further research is required to determine the effect of high intensity UVA radiation on other ocular structures with larger group of patients and long-term follow up.

Keywords: Keratoconus; Prevalence; Epithelium-off corneal crosslinking

Full Text:



Goebels S, Eppig T, Seitz B, Langenbucher A. Intraindividual Keratoconus Progression. Klin Monatsbl Augenheilkd 2017;234(8):1010–4.

Jhanji V, Sharma N, Vajpayee RB. Management of keratoconus: current scenario. Br J Ophthalmol 2010;95(8):1044–50.

Rodrigues FD, Santos GC, Gonçalves S, Ferreira CC, Salgado-Borges J. Sequential management of keratoconus treatment. Int J Kerat Ect Cor Dis 2012;1(3):201–4.

Romero-Jiménez M, Santodomingo-Rubido J, Flores-Rodríguez P, González-Méijome JM. Short-term corneal changes with gas-permeable contact lens wear in keratoconus subjects: A comparison of two fitting approaches. J Optom 2015;8(1):48–55.

Gomes JA, Tan D, Rapuano CJ, Belin MW, Ambrósio R Jr, Guell JL, et al. Global consensus on keratoconus and ectatic diseases. Cornea 2015;34(4):359–69.

McCall AS, Kraft S, Edelhauser HF, Kidder GW, Lundquist RR, Bradshaw HE, et al. Mechanisms of corneal tissue cross-linking in response to treatment with topical riboflavin and long-wavelength ultraviolet radiation (UVA). Invest Ophthalmol Vis Sci 2010;51(1):129–38.

Kymionis GD, Grentzelos MA, Kankariya VP, Liakopoulos DA, Portaliou DM, Tsoulnaras KI, et al. Safety of high-intensity corneal collagen crosslinking. J Cataract Refract Surg 2014;40(8):1337–40.

Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-A–induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol 2003;135(5):620–7.

Raiskup F, Theuring A, Pillunat LE, Spoerl E. Corneal collagen crosslinking with riboflavin and ultraviolet-A light in progressive keratoconus: ten-year results. J Cataract Refract Surg 2015;41(1):41–6.

Tsatsos M, MacGregor C, Kopsachilis N, Anderson D. Is accelerated corneal collagen cross-linking for keratoconus the way forward? Yes. Eye (Lond) 2014;28(7):784–5.

Asri D, Touboul D, Fournié P, Malet F, Garra C, Gallois A, et al. Corneal collagen crosslinking in progressive keratoconus: multicenter results from the French National Reference Center for Keratoconus. J Cataract Refract Surg 2011;37(12):2137–43.

Jankov MR 2nd, Hafezi F, Beko M, Ignjatovic Z, Djurovic B, Markovic V, et al. Corneal Cross-linking for the treatment of keratoconus: preliminary results. Arq Bras Oftalmol 2008;71(6):813–8.

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(7):S720–5.

Mazzotta C, Traversi C, Baiocchi S, Sergio P, Caporossi T, Caporossi A. Conservative treatment of keratoconus by riboflavin-uva-induced cross-linking of corneal collagen: qualitative investigation. Eur J Ophthalmol 2006;16(4):530–5.

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(5):796–801.

Kymionis GD, Portaliou DM, Diakonis VF, Kounis GA, Panagopoulou SI, Grentzelos MA. Corneal collagen cross-linking with riboflavin and ultraviolet-A irradiation in patients with thin corneas. Am J Ophthalmol 2012;153(1):24–8.

Kymionis GD, Tsoulnaras KI, Liakopoulos DA, Skatharoudi CA, Grentzelos MA, Tsakalis NG. Corneal stromal demarcation line depth following standard and a modified high intensity corneal cross-linking protocol. J Refract Surg 2016;32(4):218–22.

Çınar Y, Cingü AK, Türkcü FM, Çınar T, Yüksel H, Özkurt ZG, et al. Comparison of accelerated and conventional corneal collagen cross-linking for progressive keratoconus. Cutan Ocul Toxicol 2014;33(3):218–22.

Elbaz U, Shen C, Lichtinger A, Zauberman NA, Goldich Y, Chan CC, et al. Accelerated (9-mW/cm2) corneal collagen crosslinking for keratoconus—a 1-year follow-up. Cornea 2014;33(8):769–73.

Ulusoy DM, Göktaş E, Duru N, Özköse A, Ataş M, Yuvacı İ, et al. Accelerated corneal crosslinking for treatment of progressive keratoconus in pediatric patients. Eur J Ophthalmol 2017;27(3):319–25.

Sherif AM. Accelerated versus conventional corneal collagen cross-linking in the treatment of mild keratoconus: a comparative study. Clin Ophthalmol 2014;8:1435–40.

Akbar B, Intisar-ul-Haq R, Ishaq M, Fawad A, Arzoo S, Siddique K. Comparison of transepithelial corneal crosslinking with epithelium-off crosslinking (epithelium-off CXL) in adult Pakistani population with progressive keratoconus. Taiwan J Ophthalmol 2017;7(4):185–90.


  • There are currently no refbacks.

Contact Number: +92-992-382571

email: [jamc] [@] []