Predictive Factors of the Standard Corneal Collagen Cross-Linking Outcomes among Keratoconus Patients in Palestine رسالة ماجستير

Abstract

Background: Corneal cross-linking is the first line treatment for slowing the progression of Keratoconus, a progressive corneal ectatic disorder. Limited standardized guidelines are available on the impact of preoperative factors on the clinical outcomes of corneal CXL. Purpose: To determine the effects of pre-operative presumed predictive factors on clinical and topographic outcomes in adults with keratoconus1 year following standard corneal cross-linking treatment. Methods: A retrospective chart review study included 30 keratoconus patients (46 eyes) who underwent standard corneal collagen cross-linking treatment in an ophthalmology tertiary center in the city of Nablus, West Bank during the period from August 2019 until August 2021. Post-treatment best-corrected visual acuity and maximum keratometry were considered to be the predictive variables. Univariable analyses were performed to determine correlations between baseline parameters and follow-up measurements. Correlating factors (P ≤ .20) were then entered into a multivariable linear regression analysis. finally a subgroup analyses were performed according to the age (≥25years and < 25 years), gender (Male and Female), family history of KC (positive and negative), smoking history (positive and negative), atopic constitution history (positive and negative), pre-operative K max (≥54 D and <54 D), pre-operative BCVA (<0.2 and ≥0.2 XI Log MAR), pre-operative UCVA (<0.6 and ≥0.6 Log MAR) pre-operative corneal thickness (<446 μ and ≥446 μ), pre-operative corneal apex thickness (<461 μ and ≥461 μ), pre-operative SEMR (≥-2.6 D and < -2.60 D) and the cone locations (central or eccentric) determine the associations between preoperative patient characteristics and outcomes (changes in visual acuity and maximum keratometry) of CXL treatment. Results: multivariate analysis identified negative family history of keratoconus as a significant factor for predicting of post-operative best-corrected visual acuity (ß coefficient = 0.343 P =0.040), while Posttreatment maximum keratometry could be predicted based on pretreatment apical pachymetry (ß coefficient = 0.939, P =0.036). Conclusions: Results of this study found that in patients with progressive keratoconus, family history, pre-operative best-corrected visual acuity, pre-operative corneal thickness, and smoking history appear to affect the success of the corneal cross-linking treatment.