APR 18, 2011
Previous studies have found a strong direct association between corneal biomechanical metrics and central corneal thickness (CCT) measurements in keratoconic eyes, but none used controls that were matched using known variables.
That's why the authors of this study investigated the corneal biomechanical metrics in a population of eyes with keratoconus with "normal" central corneal thickness (≥520 μm) with age-, sex-, and CCT-matched healthy controls.
Using the Ocular Response Analyzer, researchers prospectively measured the corneal hysteresis (CH) and corneal resistance factor (CRF) in 19 patients with keratoconus and a CCT of ≥520 μm and compared the results to healthy matched controls.
They found that CH and CRF were statistically lower in the keratoconus group than controls. However, due to the large overlap in values between groups, both CH and CRF had low sensitivity and specificity for discriminating abnormal corneas.