Intereye Symmetry of 24-Hour Intraocular Pressure-related Patterns in Untreated Glaucoma Patients Using a Contact Lens Sensor.

Purpose: Scarce data are available on the symmetry of 24-hour intraocular pressure (IOP) variations between fellow eyes of glaucoma patients, and such evidence could have profound consequences on the interpretation of monocular therapeutic trials. The objective is to evaluate the intereye correlation of continuously measured circadian IOP-related patterns in untreated glaucoma patients.
Methods: In this single-center prospective study, a total of 29 untreated patients with open-angle glaucoma underwent bilateral ambulatory 24-hour monitoring of IOP-related patterns using a contact lens sensor (CLS; SENSIMED Triggerfish). IOP was measured before and after CLS monitoring using Goldmann applanation tonometry. Intereye agreement of 24-hour patterns was calculated using Spearman correlation (r) of raw data and after cosinor rhythmometry modeling.
Results: Complete bilateral CLS data could be obtained in 20 patients (mean age: 55.5±15.7 y; 51.7% women). On average, intereye correlation was r=0.76±0.19 (range: 0.16 to 0.95) and r=0.77±0.15 (range: 0.49 to 0.91), after excluding 8 patients with lower quality recordings. Cosine rhythmometry modeling showed mean acrophases occurring at 4:21±2:20 AM in left eyes and 3:39±1:50 AM in right eyes (r=0.48; P=0.034). Mean acrophase amplitude was 110.9±51.9 for left eyes and 107.8±46.2 for right eyes (r=0.79; P<0.001). No serious adverse events related to CLS monitoring were recorded. Transient conjunctival hyperemia (13 patients) and blurred vision (11 patients) were the most frequent adverse events.
Conclusions: In this group of untreated glaucoma patients, there was good intereye agreement for circadian IOP-related patterns using the CLS. These results show a higher degree of intereye symmetry, in terms of IOP peak timings and amplitudes, than previously reported with standard tonometry.