A Game-Changing Diagnostic Tool

IOP remains the only modifiable risk factor for glaucoma, but brief, infrequent office visits provide a limited snapshot of patients’ IOP trends. Studies have shown that most peak IOP values occur outside of standard office hours.^1,2

Home tonometry has recently become a game-changing diagnostic tool in my practice. Self-administered rebound tonometry enables patients to check their IOP frequently at home without topical anesthesia. IOP data acquired outside of office hours provide a more comprehensive clinical picture, analogous to what cardiologists and endocrinologists can learn from devices such as Holter monitors and continuous glucose sensors. Earlier recognition of IOP elevation via home tonometry facilitates more timely intervention because we clinicians no longer must wait for demonstrated structural or functional progression to adjust treatment regimens. In addition to informing our clinical decision-making, home tonometry empowers patients to be more actively engaged in their glaucoma care.

Next-Gen Glaucoma Self-Care and Home Monitoring

 

A common clinical scenario in which I find home tonometry to be particularly useful is that of a patient experiencing visual field progression despite excellent medication adherence and IOP that appears to be well controlled at office visits. Home tonometry has helped me identify unexpectedly high peak IOPs, which usually occur early in the morning and/or late at night. I might offer less aggressive interventions such as selective laser trabeculoplasty or angle-based MIGS as a first procedure to such patients—especially if they have early disease—to blunt their intermittent IOP spikes. On the other hand, in patients demonstrating visual field progression at low IOPs whose home tonometry results rule out occult IOP spikes, I may recommend a more aggressive approach, such as filtering surgery. Repeating home tonometry postoperatively also helps me confirm that a given procedure has successfully reduced peak IOPs, mean IOPs, and IOP fluctuations, providing reassurance to both my patients and me.

Home rebound tonometry in its current state is not without limitations. For example, it cannot monitor IOP continuously, including during normal activities and sleep. Studies have shown, moreover, that as many as 30% to 40% of patients are unable to use this technology.^3,4 In addition, the costs of renting or purchasing home tonometry devices are prohibitive for many patients. I look forward to the future availability of remote IOP-monitoring technologies that are more informative, tolerable, and affordable. Smart contact lenses and implantable microsensors that provide 24-hour IOP measurements are in the pipeline. Patients are already embracing wearable technology to track behaviors such as fitness and sleep, and advances in home glaucoma monitoring could enable them to take greater control over their health and well-being.