Corneal Biomechanical Properties in Keratoconic, Myopic, and Hyperopic Eyes as Measured with a Scheimpflugbased Tonometer
Irina S Barequet, Nadav Shoshany, Ran Rutenberg, David Zadok
Biomechanical, Cornea, Keratoconus, Scheimpflug based tonometer.
Citation Information :
Barequet IS, Shoshany N, Rutenberg R, Zadok D. Corneal Biomechanical Properties in Keratoconic, Myopic, and Hyperopic Eyes as Measured with a Scheimpflugbased Tonometer. Int J Kerat Ect Cor Dis 2018; 7 (1):19-25.
Aim: To evaluate corneal biomechanical properties in myopic (MY), hyperopic (HY), and keratoconic (KCN) eyes as measured with the Corvis ST, a newly developed Scheimpflugbased noncontact tonometer with features of visualization and measurement of the corneal deformation response to an air impulse.
Materials and methods: Corneal biomechanical properties measurements were obtained for 34 KCN, 109 MY, and 12 HY patients. Statistical analysis was performed using logistic regression in order to control for confounders (intraocular pressure, pachymetry, and first applanation time) and to identify optimal combinations of parameters for KCN detection.
Results: No single parameter was significantly different between KCN and either MY or HY after controlling for cofounders. The two combinations of parameters that were assessed achieved low specificity and sensitivity values.
Conclusion: The parameters and their combinations overlapped significantly between the groups and could not provide an adequate means to differentiate KCN from healthy corneas. Therefore, with regard to KCN, the Corvis ST can only be used as an adjunct to the clinical examination and customary diagnostic tools.
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