[I have tested for you. Pachymetry devices]

Different techniques are currently available to measure central corneal thickness: optical pachymetry, ultrasound pachymetry, optical coherence pachymetry, slit-scanning pachymetry, specular microscopy, and confocal microscopy. Ultrasound pachymetry is the gold standard. It is a noncontact and rapid technique with high precision, approximately 1%. The correlation between optical coherence pachymetry and ultrasound pachymetry is high, with a 0.99 correlation coefficient. Nevertheless, optical coherence pachymetry measurements seem underestimated compared to ultrasound pachymetry measurements. Correlation of ultrasound pachymetry with the other techniques is less satisfying. If the ultrasound probe can be decontaminated for each patient, ultrasound pachymetry seems to be the best technique for measuring central corneal thickness. Otherwise, optical coherence pachymetry seems to be the most advantageous technique.