Corneal hysteresis has attracted considerable interest in recent years. Corneal hysteresis is a measure of the viscoelastic dampening of the cornea, and it can be estimated by analyzing corneal responses to deformation induced by an air pulse using a commercially available instrument (Ocular Response Analyzer; Reichert).

The measurement of corneal hysteresis has been shown to be associated with the risk of glaucomatous progression.1-3 In a prospective, longitudinal study, my colleagues and I found that patients with lower hysteresis had significantly faster rates of progressive visual field loss compared to those with higher hysteresis.3 Importantly, the hysteresis measurements had a stronger ability to predict visual field progression than measurements of corneal thickness. It is hypothesized that these results may be explained by a relationship between corneal hysteresis and the structures in the back of the eye, the lamina cribrosa, and peripapillary sclera.

The ability of the cornea to resist deformation may reflect the constitution of its extracellular matrix, which could, in turn, be related to the extracellular matrix composition of these posterior ocular tissues linked to glaucomatous damage. An eye with a more deformable cornea or with a lower hysteresis could have an optic disc that is more susceptible to IOP-related damage. Although this is an attractive hypothesis to explain the significance of hysteresis as a risk factor of glaucoma, it still remains to be proven.

Felipe A. Medeiros, MD, PhD, is the Ben and Wanda Hildyard chair for diseases of the eye and a professor of ophthalmology at the University of California, San Diego. He has received research support from Reichert. Dr. Medeiros may be reached at fmedeiros@ucsd.edu.

  1. Congdon NG, Broman AT, Bandeen-Roche K, et al. Central corneal thickness and corneal hysteresis associated with glaucoma damage. Am J Ophthalmol. 2006;141(5):868-875.
  2. De Moraes CV, Hill V, Tello C, Liebmann JM, Ritch R. Lower corneal hysteresis is associated with more rapid glaucomatous visual field progression. J Glaucoma. 2012;21(4):209-213.
  3. Medeiros FA, Meira-Freitas D, Lisboa R, et al. Corneal hysteresis as a risk factor for glaucoma progression: a prospective longitudinal study. Ophthalmology. 2013;120(8):1533-1540.