Corneal Distortion and Corneal Morphological Parameters in Naïve Eyes Analyzed with a Scheimpflug Camera
Abstract
Background: The study of the corneal biomechanical properties (CBP) is gaining always more interest, thanks to the applications to refractive surgery and to the overall management of several corneal diseases.
Purpose: To analyze the eventual relationships between corneal distortion and morphologic features in healthy subjects.
Methods: one eye of one hundred and fifty-two healthy participants, 87 women and 65 men, aging from 23 to 65 years old, were evaluated in this study. Every eye underwent a complete clinical examination, that included also a tomographic scan using Pentacam HR (Oculus, Wetzlar, Germany) and a biomechanical evaluation using Corvis ST (Oculus, Wetzlar, Germany). Linear regressions among refractive defect, corneal volume (CV), anterior corneal curvature and central corneal thickness (CCT) vs corneal biomechanical features provided by Corvis ST have been ran using SPSS software version 18.0.
Results: Corneal distortion factors showed a low correlation both with corneal morphological parameters and with refractive defect. No significant correlations (p> 0.01) were found among morphologic and biomechanical features evaluated.
Discussion: results observed in this study could help in recognize the healthy range of values of CBP parameters provided by CST. This information could be very useful in many ophthalmology topics such as the accurate IOP measurement, the early diagnosis of corneal degenerations, such as keratoconous, and the screening of subject undergoing refractive surgery.
Conclusions: even if data of this study need to be confirmed in further ones with larger populations, results here observed suggest that Corvis ST is a device providing an evaluation of corneal distortion not influenced by morphological corneal factors. This information could help in better screening and managing the diseased corneas.
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