Angle Kappa measurement pre-keratorefractive and post-keratorefractive surgery using Orbscan 3

Aim of the study Measurement of the mean angle Kappa pre-keratorefractive and post-keratorefractive surgery utilizing Orbscan 3. Patients and methods This retrospective study was conducted on patients who had refractive surgeries, group A included patients who underwent Lasik and group B included patients who underwent Photo Refractive Keratectomy (PRK). Mean age from 18 to 45 years. Preoperative, 1-week, and 1-month postoperative assessments included detailed ocular examination, slit-scanning topography done by Orbscan 3, and total ocular aberrations by Zywave 3 were done. Results The study comprised 146 eyes of 75 individuals. Preoperative data demonstrated that angle Kappa mean in Lasik group (group A) was 2.38±1.54 at 147.05±96.94, in PRK group (group B) was 2.31±1.17 at 137.67±85.7. Paired mean differences of the two groups between preoperative data and 1-week postoperative show no statistically significant difference in central corneal thickness (CCT) nor angle Kappa values. Paired mean differences of the two groups between preoperative data and 1-month postoperative show no statistically significant difference regarding CCT nor angle Kappa values. Preoperative, 1-week postoperative, and 1-month postoperative correlation of angle Kappa to refractive error, spherical equivalent, average K-reading, CCT and axial length, showed that both groups had a positive correlation with axial length. Conclusion Keratorefractive surgeries do not affect angle Kappa or its intercept measurements.