A recent study compared central corneal thickness (CCT) measurements of scanning-slit topography, ultrasonic pachymetry and OCT in diabetic eyes with and without diabetic retinopathy (DR). While the researchers found that all three methods correlated well and were in agreement, scanning-slit topography measurements were higher compared with the other two.

The study measured the CCT of 96 eyes with the three different devices and found the measure was statistically insignificantly different between the groups with and without DR. The researchers also found no correlation of CCT with disease duration, severity of DR and previous laser therapy.

The researchers emphasize that accurate CCT measurement is important in many ophthalmic circumstances, such as accurate IOP measurements, preoperative evaluation in ocular surgeries, assessment of postoperative healing process, planning of keratorefractive procedures and corneal endothelial function evaluation in diabetic patients. Their study also draws attention to the value of anterior segment OCT for CCT measurements because it is a non-contact method and correlates well with ultrasound pachymetry.