• Abida Fida Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi
  • Sadia Humayun Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi
  • Iram Fatima Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi
  • Imran Basit Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi
  • Mazhar Ishaq
  • Fida Hussain AFIP Rawalpindi


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

Author Biographies

Abida Fida, Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi

Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi

Sadia Humayun, Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi

Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi

Iram Fatima, Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi

Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi

Fida Hussain, AFIP Rawalpindi

Nuclear Medical Centre AFIP Rawalpindi


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