Study of central corneal thickness using non-contact techniques: Specular microscopy (Nidek CEM-530), corneal tomography (Pentacam HR), and optical coherence tomography (Cirrus HD-OCT 5000) in healthy adult patients

Objective: To study and compare the value of central corneal thickness in a healthy adult population, using different non-contact techniques from daily clinical practice. Method: This work examines and compares the pachymetric measurements of 71 eyes of 36 healthy adult patients. Corneal thickness was evaluated using three non-contact instruments: a CEM-530 specular microscope (Nidek), Pentacam HR corneal tomography (Oculus), and Cirrus HD-OCT 5000 optical coherence tomography (Carl Zeiss Meditec). Tests were performed consecutively by a single observer in the same session and under the same environmental conditions. Results: The results obtained using the three devices are interchangeable, given that no statistically significant difference was observed among them. The study did not find statistically significant difference with respect to gender either. Conclusion: These three non-contact methods for the measurement of corneal central pachymetry are a reliable alternative to ultrasonic contact pachymetry.