Estimation of 24-Hour Intraocular Pressure Peak Timing and Variation Using a Contact Lens Sensor.

John H K Liu,Kaweh Mansouri,Robert N Weinreb

doi:10.1371/journal.pone.0129529

John H K Liu, Kaweh Mansouri + Show 1 more

Open Access

https://doi.org/10.1371/journal.pone.0129529

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Abstract

PurposeTo compare estimates of 24-hour intraocular pressure (IOP) peak timing and variation obtained using a contact lens sensor (CLS) and using a pneumatonometer.MethodsLaboratory data collected from 30 healthy volunteers (ages, 20-66 years) in a randomized, controlled clinical trial were analyzed. Participants were housed for 24 hours in a sleep laboratory. One randomly selected right or left eye was fitted with a CLS that monitored circumferential curvature in the corneoscleral region related to the change of IOP. Electronic output signals of 30 seconds were averaged and recorded every 5 minutes. In the contralateral eye, habitual IOP measurements were taken using a pneumatonometer once every two hours. Simulated 24-hour rhythms in both eyes were determined by cosinor fitting. Simulated peak timings (acrophases) and simulated data variations (amplitudes) were compared between the paired eyes.ResultsBilateral change patterns of average 24-hour data for the group were in parallel. The simulated peak timing in the CLS fitted eye occurred at 4:44 AM ± 210 min (mean ± SD) and the IOP peak timing in the contralateral eye at 4:11 AM ± 120 min (P=0.256, Wilcoxon signed-rank test). There was no significant correlation between the simulated data variations in the paired eyes (P=0.820, linear regression).ConclusionsThe 24-hour CLS data showed a simulated peak timing close to the 24-hour IOP peak timing obtained using the pneumatonometer. However, the simulated variations of 24-hour data in the paired eyes were not correlated. Estimated 24-hour IOP rhythms using the two devices should not be considered interchangeable.

Highlights

Measurements of intraocular pressure (IOP) outside office hours can provide useful information for glaucoma diagnosis and treatment [1]-[6]
The simulated peak timing in the contact lens sensor (CLS) fitted eye occurred at 4:44 AM ± 210 min and the IOP peak timing in the contralateral eye at 4:11 AM ± 120 min (P=0.256, Wilcoxon signedrank test)
24-Hr IOP Rhythm Determined by Contact Lens Sensor declare

Summary

Introduction

Measurements of intraocular pressure (IOP) outside office hours can provide useful information for glaucoma diagnosis and treatment [1]-[6]. Examination of IOP during a 24-hour period is usually performed with subjects housed in a sleep laboratory or an inpatient facility [7][9]. Data are typically collected once every few hours and there is a need of awakening subjects for tonometry during the sleep period. A wireless contact lens sensor (CLS, Triggerfish; Sensimed, Lausanne, Switzerland) has been developed for monitoring 24-hour IOP at home without the need of awakening subjects during sleep [10], [11]. Several reports have demonstrated good tolerability of the CLS for 24-hour recordings, but the clinical applications of the CLS need to be investigated [12]-[19]. How to convert the CLS signals to accurate IOP values is currently unknown, but a unique 24-hour CLS signal pattern is readily available for each test individual

Methods

Discussion

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