Tip of the Month
Publishing date: June 2017
The Science behind the Tip
Corneal hysteresis is a biomechanical property of the cornea relating to its elasticity. The measurement of corneal hysteresis is emerging as an important indicator of risk in glaucoma: a low value is associated with an increased risk of progression and advanced glaucomatous damage (1,2).
The chronic use of prostaglandin analogues (PGA) may change the biomechanical properties of the cornea in glaucoma patients, resulting in a decrease in the values of corneal hysteresis, corneal resistance factor and central corneal thickness (3). A recent prospective, interventional case-controlled study reveals that the use of PGAs has an effect in time on the accuracy of IOP measurements when taken with Goldmann applanation tonometry, leading to an average underestimation of IOP of 1.2mmHg (3).
Contributor: Dr Gordana Sunaric Mégevand- Geneva
1. Congdon NG, Broman AT, Bandean-Roche K et al. Central corneal thickness and corneal hysteresis associated with glaucoma damage. Am J Ophthalmol 2006; 141 : 868-75
2. 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 : 1533-40
3. Meda R, Wang Q, Paoloni D et al. The impact of chronic use of prostaglandin analogues on the biomechanic properties of the cornea in patients with primary open-angle glaucoma. Br J Ophthalmol 2017; 101 : 120-125.
Tip Reviewer: Roger Hitchings
Tip Editors: John Salmon and Gordana Sunaric Mégevand