An Algorithm to Convert Optical Coherence Tomography Central Corneal Thickness Values to Ultrasound Central Corneal Thickness Values and its Corresponding Correction Factor
Keywords:
Algorithm, Convert, Central Corneal Thickness, Ultrasound Pachymetry, Optical Coherent TomographyAbstract
Background: Measuring Central Corneal Thickness (CCT) using Optical Coherence Tomography (OCT) is more convenient for the
doctor and patient as compared to the Ultrasound (USS) measurement. OCT is a non-contact test, anesthetic drops are not used, there is no risk of abrasion or infection and the exact position of the central cornea is measured as OCT maps out the center. Nevertheless, OCT values have been found to be statistically significantly lower than the USS measures, 1-8 so both measures cannot be
interchanged. Hence an algorithm is needed to convert OCT values to USS values after which the relevant intraocular pressure (IOP) correction factor can be applied in patient management.
Aim: To develop an algorithm to convert OCT CCT values to USS CCT values and apply the corresponding correction factor.
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