Association of Ambulatory Blood Pressure and Other Factors With Intraocular Pressure-Related 24-Hour Contact Lens Sensor Profile in Untreated Glaucoma.

Purpose: To investigate the association of diurnal blood pressure (BP) and other factors with the intraocular pressure (IOP)-related 24-hour contact lens sensor (CLS) profile of patients with untreated glaucoma. Methods: The prospective study included 82 patients with untreated normal-tension glaucoma. CLS measurements and ambulatory BP monitoring were performed simultaneously for 24 hours. The association between the mean arterial pressure (MAP) and CLS profile was examined for the daytime and nocturnal periods using linear regression analysis. The associations between other factors and the CLS profile were also examined. Results: Multivariate analysis of data from 63 eligible patients showed that higher average MAPs were significantly associated with larger average nocturnal CLS values (ß coefficient = 0.273; P = 0.023); a larger increase in the last CLS value (ß coefficient = 0.366; P = 0.003); larger standard deviations (SDs) of CLS values for the daytime, nocturnal, and 24-hour periods (ß coefficient = 0.407, 0.293, and 0.375; P < 0.001, P = 0.032 and 0.002, respectively); and higher average ocular pulse frequencies for the daytime, nocturnal, and 24-hour periods (ß coefficient = 0.268, 0.380, and 0.403; P = 0.029, 0.002, and 0.001, respectively). Thicker subfoveal choroids and shorter axial length were significantly associated with larger SDs and larger average CLS values, respectively. Smaller anterior chamber volume and lower corneal hysteresis were associated with larger SDs or larger average ocular pulse amplitude. Conclusions: Ambulatory BP and several ocular parameters were significantly associated with various parameters of the 24-hour CLS profile. Translational Relevance: Ambulatory BP and ocular parameters may be modifiers of the 24-hour IOP-related profile of CLS.

Diurnal Variation of Corneal Hysteresis in Patients With Untreated Primary Open Angle Glaucoma and Normal Individuals.

PRCIS: Corneal hysteresis in both patients with untreated open angle glaucoma and normal individuals demonstrated significant diurnal variation independent of confounding factors and was higher in the nighttime than in the daytime. PURPOSE: To investigate diurnal variations in corneal hysteresis (CH) in patients with untreated primary open angle glaucoma (POAG) and normal individuals by using an ocular response analyzer. MATERIALS AND METHODS: This prospective study included 72 eyes of 53 patients with untreated POAG and 53 eyes of 47 normal individuals. Intraocular pressure (IOP) and CH were measured using Goldmann applanation tonometry (GAT) and ocular response analyzer, respectively, every 3 hours from 9:00 to 24:00. Mixed-effects models were used to determine factors associated with CH values and CH amplitude (maximum values minus minimum values) and to examine the diurnal variations in GAT IOP and CH in each group. Significant differences between time points were defined as significant variations. RESULTS: The diurnal average GAT IOP and CH in patients with POAG were significantly higher and lower than those in normal individuals ( P =0.001, 0.002). In the multivariate analysis, the larger central corneal thickness was associated with larger CH values in POAG and normal eyes (both P <0.001). A larger amplitude of GAT IOP was significantly associated with a larger CH amplitude in POAG and normal eyes ( P =0.010, 0.013). CH, in both groups, showed similar significant diurnal variation and was higher in the nighttime than in the daytime, even after adjusting for confounding factors, while IOP showed an antiphase pattern. CONCLUSION: CH in both untreated POAG patients and normal participants demonstrated similar diurnal variations, that is, higher at night, independent of confounding factors. These findings suggest that viscoelastic properties of the cornea may fluctuate diurnally independent of IOP.