In this prospective observational trial, investigators explored whether corneal hysteresis (CH) could be used as a biomarker for identifying patients at risk for developing glaucoma.

Study design

The cohort comprised 199 glaucoma suspects (287 eyes) who were followed for an average of 3.9 years. All eyes had normal visual fields (VFs) and CH measurements taken at baseline. Development of glaucoma was defined as 3 consecutive abnormal standard automated perimetry tests during follow-up.

Outcomes

Repeatable VF defects developed in 54 eyes (19%) eyes during follow-up. All eyes in this group had significantly lower CH measurement at baseline compared with those who did not develop VF defects (9.5 mm Hg vs 10.2 mm Hg, P=0.012).

A multivariate analysis revealed that each 1-mm Hg drop in baseline CH was associated with a 21% increased risk of developing glaucoma during follow-up.

Limitations

This study failed to identify IOP as a risk factor for glaucoma. The authors believe this is due to the observational rather than interventional design, and participants were treated at the discretion of the attending ophthalmologist during follow-up.

Clinical significance

Previous studies have already identified decreased CH as a risk factor for worsening glaucoma and faster VF progression among individuals with glaucoma. This study shows that CH is an independent risk factor for the development of glaucoma among glaucoma suspects.

Integrating CH will help clinicians better stratify glaucoma suspects and perhaps lower the threshold for treatment, thereby allowing us to take a more proactive approach while the nerve is still healthy.