IOP Isn’t a Number — It’s a Waveform: Why Ophthalmology Must Shift From Snapshots to Continuous Monitoring

For decades, intraocular pressure (IOP) has been treated as a discrete measurement — a number captured during a clinic visit, often with the implicit assumption that this value reflects a patient’s true pressure profile. But mounting evidence, paired with a deeper understanding of ocular physiology, tells a very different story: IOP is not a number. IOP is a dynamic waveform.

Just as cardiology abandoned single-point blood pressure readings in favor of longitudinal, continuous data, ophthalmology now stands at a similar inflection point. The notion that a few snapshots per year can adequately characterize a biological variable that fluctuates minute-to-minute is no longer tenable.

Patients experience IOP peaks and troughs driven by circadian rhythm, posture, activity, hydration, medication timing, and micro-physiologic events that no clinic measurement can reliably capture. Numerous studies have shown that damaging IOP spikes often occur outside office hours: at night, during early morning hours, or during routine daily activities.

These transient events are invisible to Goldmann applanation or tonometry-based home devices. Yet they may be the very fluctuations that accelerate optic nerve damage, particularly in normal-tension glaucoma and patients deemed “well controlled” by traditional measures.

Think of it this way: if cardiologists measured blood pressure only three times a year, no one would consider that adequate care. The same logic applies to glaucoma. IOP is a waveform — a continuous physiologic signal with amplitude, frequency, variability, and patterns unique to each patient. Understanding this pattern is increasingly recognized as essential to optimizing treatment, truly assessing risk, and finally personalizing therapy.

This is where continuous sensing technology becomes transformative. Platforms like those being developed at Injectsense demonstrate that it’s now possible to capture the actual IOP waveform in its native environment — effortlessly, passively, and continuously. Suddenly, clinicians can observe nocturnal peaks, treatment response curves, variability signatures, and real-world pressure behavior that has never been visible before.

Continuous monitoring won’t replace clinical judgment; it will provide a highly reliable decision-making foundation. With a richer data stream, ophthalmologists gain the ability to identify high-risk patterns early, tailor interventions precisely, and understand why some patients progress despite seemingly “normal” pressures.

The medical community is already shifting toward continuous physiologic data in cardiology, neurology, and endocrinology. Ophthalmology is next. It’s time to recognize that IOP has always been a waveform — we just haven’t been able to see it.