Continuous Monitoring of Intraocular Pressure: An Overview of New Techniques

Elevated intraocular pressure (IOP) is the main risk factor for glaucoma and is currently the only treatable risk factor. IOP is dynamic with regular circadian variations and random short-term and long-term fluctuations. Current glaucoma management is mostly based on single IOP measurements during office visits which may not accurately represent a patient’s 24-h pressure profile. Most of glaucoma patients have their highest IOP outside clinic hours, usually during the nocturnal period. Currently, the only available approach for 24-h IOP monitoring is by using repeated tonometry which is inconvenient, expensive, and does not provide continuous monitoring of IOP. The goal of continuous IOP monitoring is to provide automated 24-h ambulatory recording of IOP. In this article, we review the existing technologies for IOP monitoring and evaluate new innovative methods for continuous 24-h IOP monitoring, including temporary non-invasive and permanent invasive approaches that currently being developed.