Corneal biomechanical metrics in eyes with refraction of -19.00 to +9.00 D in healthy Brazilian patients.

PURPOSE To evaluate corneal biomechanical metrics with tomographic parameters (given by the Oculus Pentacam) and refractive data in a population of healthy Brazilian patients. METHODS Observational, cross-sectional study of 150 consecutive patients (53 men and 97 women; 260 eyes). Age, gender, central keratometric readings (central K), central corneal thickness (CCT), anterior chamber depth (ACD), spherical equivalent refraction, corneal hysteresis, and corneal resistance factor (CRF) were assessed and analyzed. RESULTS Mean patient age was 46.5+/-21.04 years, average central K was 43.59+/-1.54 diopters (D), CCT was 545.05+/-35.41 microm, ACD was 2.96+/-0.52 mm, spherical equivalent refraction was -1.16+/-3.48 D, corneal hysteresis was 10.17+/-1.82, and CRF was 10.14+/-1.8 (range: 5.45 to 15.1). Mean CRF and corneal hysteresis were distinct among gender: CRF 10.326 in women and 9.810 in men (P=.0266); corneal hysteresis 10.421 in women and 9.727 in men (P=.0031). A negative correlation was found between both CRF and corneal hysteresis with age (r=-0.1255, P=.0434; and r=-0.2445, P=.0001, respectively). No association was found between CRF and average central K (r=0.0633, P=.3086), ACD (r=-0.0474, P=.4498), or spherical equivalent refraction (r=0.1028, P=.1061). Corneal hysteresis was not associated with age and average central K (r=0.0572, P=.3573), ACD (r=0.0060, P=.9236), or spherical equivalent refraction (r=0.0975, P=.1253). Corneal resistance factor and corneal hysteresis were positively associated with CCT (r=0.5760, P=0; and r=0.4655, P=0, respectively). CONCLUSIONS Corneal biomechanical metrics of healthy Brazilian patients were associated with CCT, gender, and age. Corneal steepness, ACD, and spherical equivalent refraction did not affect comeal hysteresis and CRF values in the studied population.

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