Lower corneal hysteresis increases risk for visual field impairment in glaucoma
Corneal hysteresis was a significant risk factor for glaucomatous central and peripheral visual field progression, according to a study published in the American Journal of Ophthalmology.
“Prior studies have found lower CH [corneal hysteresis] to be associated with an increased rate of functional and structural deterioration in glaucoma patients,” Alireza Kamalipour, MD, MPH, of the Shiley Eye Institute at the University of California, San Diego, and colleagues wrote. “In this study, the event-based multivariable analysis showed that 1 mm Hg lower CH corresponds to a 35% increase in the odds of central VF [visual field] progression after adjusting for other covariates.”
In an observational cohort study, Kamalipour and colleagues analyzed 143 participants from two prospective longitudinal studies to evaluate optic nerve structure and visual function in glaucoma. More than 75% of participants were already on ocular hypotensive eye drops at study onset.
Investigators monitored participants for an average of 4.8 years, during which time they conducted annual comprehensive ophthalmologic examinations, as well as semiannual assessments of automated perimetry (a minimum of five 10-2 and 24-2 VF tests) and IOP.
Of 103 patients with glaucoma and 40 patients with suspected glaucoma (mean age, 68.4 years; 50.3% women), eyes with glaucoma had lower baseline IOP, lower mean IOP during follow-up, worse baseline 24-2 and 10-2 mean deviations (MDs) and higher baseline 24-2 and 10-2 pattern standard deviations (PSDs) than glaucoma suspect eyes (all P < .05).
In the univariable trend-based analysis, lower baseline CH was associated with 10-2 and 24-2 VF progression, while in the multivariable trend-based analyses, lower CH was associated with a faster rate of decline in 10-2 MD but not with 24-2 MD.
“Given the substantial influence of central VF impairment on the quality of life, clinicians should consider using CH to assess the risk of progression in primary open-angle glaucoma patients, including those with early disease,” Kamalipour and colleagues concluded.