Corneal Hysteresis and Progressive Retinal Nerve Fiber Layer Loss in Glaucoma

Abstract

Purpose To investigate the relationship between corneal hysteresis (CH) and progressive retinal nerve fiber layer (RNFL) loss in a cohort of patients with glaucoma followed prospectively over time. Design Prospective observational cohort study. Methods One-hundred and eighty-six eyes of 133 patients with glaucoma followed for an average of 3.8 ± 0.8 years, with a median of 9 visits during follow-up. The CH measurements were acquired using the Ocular Response Analyzer (Reichert Instruments, Depew, NY) and RNFL measurements were obtained at each follow up visit using spectral domain optical coherence tomography (SD-OCT). Random-coefficient models were used to investigate the relationship between baseline CH, central corneal thickness (CCT), average intraocular pressure (IOP) and rates of RNFL loss during follow up, while adjusting for potentially confounding factors. Results Average baseline RNFL thickness was 76.4 ± 18.1 μm and average baseline CH 9.2 ± 1.8 mmHg. CH had a significant effect on rates of RNFL progression. In the univariable model, including only CH as a predictive factor along with time and their interaction, each 1 mmHg lower CH was associated with a 0.13 μm/year faster rate of RNFL decline (P=0.011). A similar relationship between low CH and faster rates of RNFL loss was found using a multivariable model accounting for age, race, average IOP and CCT (P=0.015). Conclusions Lower CH was significantly associated with faster rates of RNFL loss over time. The prospective longitudinal design of this study provides further evidence that CH is an important factor to be considered in the assessment of the risk of progression in patients with glaucoma.

Association of Corneal Hysteresis With Lamina Cribrosa Curvature in Primary Open Angle Glaucoma

“…[41][42][43][44][45] The association between CH and LCCI provides a plausible explanation for the association of CH with glaucoma progression. [41][42][43][44][45] In eyes with smaller hysteresis, pressure would not be dissipated too much. Thus, a higher proportion of IOP-derived energy would be used in elastic changes resulting in greater LC deformation (Fig.…”

Structural and biomechanical corneal differences between patients suffering from primary congenital glaucoma and healthy volunteers

“…) and with faster rates of retinal nerve fibre layer (RNFL) loss over time (Zhang et al. ). In childhood glaucoma, lower CH values have been also reported (Luce ; Perucho‐González et al.…”

The association between oxidative stress and corneal hysteresis in patients with glaucoma

“…This prompted our decision to separately evaluate male and female groups, as well as older and younger, groups. Other studies have already demonstrated that low CH is associated with glaucoma progression 3,4 . Here, we evaluated the relationship between systemic antioxidative status and CH; to the best of our knowledge, this is the first study to do so.…”

“…Measurements with a score of at least 6.5 were included. Details of these techniques have been reported previously 4,26 . Statistical Analysis.…”

“…Even when IOP is stable, optic nerve head damage can vary between individuals due to differing susceptibility to glaucomatous damage 2 . Some researchers have found that glaucoma progression is related to specific material properties of the cornea, such as the strength of corneal viscoelastic damping, known as corneal hysteresis (CH) 3,4 . CH can be measured by temporarily inducing a concave deformation in the cornea with a pulse of air.…”