To compare parameters of biomechanical response of the human cornea measured as corneal
hysteresis (CH) and corneal resistance factor (CRF) in patients with diabetes mellitus
and healthy control subjects.
Department of Ophthalmology, Assaf Harofeh Medical Center, Zerifin, Israel.
In the right eye of each participant, the CH, CRF, Goldmann-correlated intraocular
pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were measured
with the Ocular Response Analyzer. Central corneal thickness (CCT) was measured by
ultrasonic pachymetry and intraocular pressure by Goldmann applanation tonometry (IOP
GAT). Findings were compared between the 2 groups (control and diabetic).
Forty diabetic patients (17 women, 23 men) and 40 healthy subjects (19 women, 21 men)
were prospectively recruited. The mean CH was 9.3 mm Hg +/- 1.4 (SD) and 10.7 +/-
1.6 mm Hg and the mean CRF was 9.6 +/- 1.6 mm Hg and 10.9 +/- 1.7 mm Hg in the control
group and diabetic group, respectively (both P < .0001). Diabetic corneas were significantly
thicker (P = .019); the mean CCT was 530.3 +/- 35.9 microm in the control group and
548.7 +/- 33.0 microm in the diabetic group. The CH and CRF remained significantly
different in multivariate analysis that included CCT. There was no statistically significant
difference between the 2 groups in IOPcc, IOPg, or IOP GAT measurements.
Diabetes mellitus affected biomechanical parameters of the human corneas, including
increased CH, CRF, and CCT. Whether this observation has implications in the clinical
management and understanding of corneal ectasia and glaucoma requires further study.