Association of central corneal thickness and 24-hour intraocular pressure fluctuation.

PURPOSE

To evaluate the association between office-hour central corneal thickness (CCT) and 24-hour intraocular pressure (IOP) fluctuation in patients with glaucoma.

DESIGN

Observational case-control study.

METHODS

Measurements of IOP were obtained every 2 hours during a 24-hour period from 52 untreated glaucoma patients and 29 age-matched normal control subjects housed in a sleep laboratory. Habitual IOP measurements were obtained using a pneumatonometer in the sitting positions during the diurnal/wake period (7 AM to 11 PM) and in the supine position during the nocturnal/sleep period (11 PM to 7 AM). CCT was measured in all subjects using ultrasound pachymetry once during office hours. The association between IOP fluctuation (peak IOP-trough IOP) during the 24-hour period and the office-hour CCT was assessed in both glaucoma patients and healthy age-matched controls using Spearman rank order correlation.

RESULTS

There was no statistically significant correlation between IOP fluctuation and CCT in glaucomatous (P=0.405) and normal subjects (P=0.456).

CONCLUSIONS

Twenty-four-hour IOP fluctuations were not correlated with single CCT measurements taken during office hours in glaucoma patients.