What Is EPOCT?

EPOCT is a protocol for OCT exams. EPOCT means "Empowering OCT". EPOCT is based on widely available OCT devices but utilizes a protocol that makes OCT more accurate. Furthermore, it enables making correlations between lifestyle factors (such as exercise, nutrition, stress, or almost anything else) and glaucoma progression.

EPOCT is a way we can find out how lifestyle factors, eye drops, and other treatments affect what matters most in glaucoma management -- your nerve fiber thickness in your retina (called RNFL thickness).

Normal OCT protocols fail to help us make those direct connections. Importantly, they also often fail to diagnose RNFL worsening (i.e., glaucoma progression) accurately enough. I give an example of that below.

EPOCT is about making full use of a technology that is widely available but currently not used to its full potential.

The current situation with OCT is a lot like the old days when all glaucoma patients only had their IOP checked once or twice a year. Back then there was a tremendous under-utilization of tonometry. Now most of us have the ability to measure our IOP every day, if we wish or have the need to do so.

With EPOCT, we now have an OCT protocol that opens up tremendous new possibilities. It empowers patients and physicians, and it doesn't require new technology or something that may or may not ever be FDA approved. It is here now -- but you'll have to put in a high degree of effort to access it. This article can help you begin to understand it, and to prepare to have a discussion with your ophthalmologist about it. It is almost certain that your ophthalmologist will not yet have heard about EPOCT in 2025. Therefore, you will need to be willing to introduce your ophthalmologist to the concept.

We've been conducting EPOCT exams on friends and family since October. This has provided us with enough OCT data to perform some interesting analyses. While it has only been about three months, several of our friends and family have more OCT scans than most glaucoma patients will have in a lifetime. For example, one participant now has over 300 scans -- something rarely, if ever, seen outside of EPOCT.

EPOCT Practicality

The primary appeal of EPOCT is its ability to answer personal, glaucoma-related questions within a short timeframe -- not years down the line. For instance, many of us wonder whether nicotinamide supplementation is beneficial for us. The same curiosity applies to peptides, insulin eye drops, DMSO, and the countless other interventions we discuss on in this community.

Without EPOCT, it’s difficult, if not impossible, to answer these questions reliably. Even future clinical studies won’t fully solve this problem. Studies provide population averages, not personalized results, and biology often varies significantly between individuals. Additionally, many interventions -- from natural supplements to meditation or experimental peptides -- may never undergo large-scale trials in our lifetimes.

Let’s consider a hypothetical: you begin nicotinamide supplementation and track your clinical test results over a few years. If you notice progression (loss of RNFL thickness) over that time, maybe nicotinamide didn't help you. Or maybe it did help, and without nicotinamide your progression would have been greater. Or maybe the RNFL changes you are seeing are just noise.

No current clinical method reliably verifies the benefits of neuroprotective interventions for an individual withing a reasonable time frame -- except potentially EPOCT.

EPOCT’s precision and rapid feedback allow us to conduct rigorous, real-time trials of interventions, scientifically and systematically. Self-experiments and small scale studies become possible, as well as reliable.

Here’s an example protocol for testing something like nicotinamide:

Testing Nicotinamide with EPOCT

1. Establish a Baseline: Use EPOCT to determine your RNFL thickness baseline over 8 weeks.

2. Begin Treatment: Start nicotinamide (or another intervention) and track RNFL thickness for 3-4 months using EPOCT.

3. Pause Treatment: Discontinue the supplement for 3 months while continuing EPOCT monitoring.

4. Restart Treatment: Resume supplementation for 3–4 months, with ongoing EPOCT monitoring.

5. Review Results: Analyze the data with your glaucoma specialist and an independent reviewer. The FitEyes community could potentially assist with this, and I’m personally willing to help.

In about 12 months, you’ll have an individualized, rigorous evaluation of a neuroprotective intervention. Critics may doubt whether RNFL changes in three months are meaningful or reliable. Standard clinical OCT testing cannot deliver this, but EPOCT is different. So how can EPOCT achieve it?

EPOCT Overcomes OCT Limitations

We’ve discussed EPOCT informally on FitEyes.com for quite some time, but here’s a more academic explanation you can share with your doctor.

EPOCT overcomes the inherent limitations of test-retest variability in OCT exams. It reliably detects smaller RNFL thickness changes and does so within shorter periods of time. This capability can be a game-changer in multiple ways, as we have discussed in prior posts. (You can search for "EPOCT" in the private FitEyes email archives to review all past discussions -- login required.)

Technical OCT Background:

The resolution of changes that can be detected from exam to exam is typically in the range of 3 to 4 microns for average RNFL thickness measurements. This is supported by studies, such as the three linked below, which show that the test-retest variability (TRV) for average RNFL thickness is around 3.89 to 4.02 microns:

• Reproducibility of peripapillary retinal nerve fiber layer thickness and optic nerve head parameters measured with cirrus HD-OCT in glaucomatous eyes - PubMed

• Reproducibility of retinal nerve fiber layer measurements across the glaucoma spectrum using optical coherence tomography - PubMed

• Reproducibility of retinal nerve fiber thickness measurements using the test-retest function of spectral OCT/SLO in normal and glaucomatous eyes - PubMed

That test-retest variability of 3-4 microns is far too large to reliably detect RNFL thickness changes between two exams. In fact, it could lead to glaucoma progression being recognized only years later and only after important RNFL losses have occurred.

The Heidelberg Spectralis OCT, which we are using for EPOCT, is a more precise OCT device. The resolution of changes in RNFL thickness that can be detected from exam to exam is approximately 1.34 to 2.39 microns for normal eyes and 1.14 to 2.25 microns for glaucomatous eyes, as indicated by studies such as this one:

• Reproducibility of retinal nerve fiber layer thickness measurements using spectral domain optical coherence tomography - PubMed

This high level of precision is due to the device's advanced eye-tracking and follow-up functions, which ensure consistent measurement locations. This is much better than standard OCT devices, and pairing the Heidelberg Spectralis with the EPOCT protocol is a game-changer.

Core EPOCT Innovations:

The EPOCT approach involves more frequent OCT exams, an idea that is far from controversial. See the following paper, for example:

• Evidence-Based Guidelines for the Number of Peripapillary OCT Scans Needed to Detect Glaucoma Worsening - PubMed

Conclusions: To diagnose RNFL worsening more accurately, the number of OCT scans must be increased compared with current clinical practice.

However, the EPOCT approach also involves:

1. Obtaining duplicate or triplicate RNFL circle scans during each exam. Once the patient is seated at the OCT device, taking these extra scans requires only a few seconds each. It’s very efficient to repeat the scans, and this dramatically improves test-retest variability with minimal time investment. The OCT scans remain easy and convenient for both subject and technician.

2. Technicians perform EPOCT with higher exam quality standards.

3. Denser scans and higher real-time averaging (ART) settings improve resolution and detail.

4. Rigorous data analysis filters out noise and identifies true trends.

Combining all these elements, EPOCT allows us to detect RNFL changes at a sub-micron level (rather than 3-4 microns) and within a few weeks or months, rather than across multiple years.Our confidence in determining whether a patient is progressing or not can be orders of magnitude higher than with traditional OCT approaches. Important decisions can be made years sooner.

The Power of EPOCT in Action

Here’s a real-world example. A patient classified as “stable” by their glaucoma specialist (and prescribed no eye drops) underwent EPOCT over three months.

The data used in the EPOCT analysis consists of:

• Initial data points: 82

• Date range: 2024-10-13 to 2025-01-19 (approximately 3 months)

• Removed due to quality: 1

• TmpSup sector outliers removed:

  • 2024-10-22: 95.00 µm (z-score: -4.70)

  • 2025-01-13: 110.00 µm (z-score: 5.30)

• Global sector outliers removed:

  • 2024-10-17: 90.00 µm (z-score: 8.36)

• Count of all items removed: 4 (4.9%)

• Final data points after all filtering: 78

By the EPOCT analysis, the temporal sector is indeed stable, and we can be highly confident of that conclusion:

Sector: Temporal
Annual Rate: 0.02 µm/year
Mann-Kendall Trend: stable
Mann-Kendall P-Value: 0.1939, Mann-Kendall Progression: False
Linear Regression P-Value: 0.9860, CI±: 0.0066

In contrast, the nasal sector -- one of the most vulnerable -- showed clear signs of progression. The “no treatment” decision, therefore, warrants reconsideration. In just three months, EPOCT identified a progression that standard clinical testing might have missed for years.

Sector: Nasal
Annual Rate: -6.58 µm/year
Mann-Kendall Trend: decreasing
Mann-Kendall P-Value: 0.0000, Mann-Kendall Progression: True
Linear Regression P-Value: 0.0000, CI±: 0.0065

There's very little doubt about that conclusion. Look at the P-Values. Look at the trend line in the plot.

We can leverage this same accuracy over short time frames to evaluate any neuroprotective or other treatments we are interested in evaluating. All lifestyle factors can be put to the test with this approach. It has the potential to revolutionize glaucoma management.

EPOCT and Home IOP Monitoring

EPOCT is highly complementary to home IOP monitoring. If one identifies glaucoma progression with EPOCT, the very first thing I would recommend is using home IOP monitoring to look for so-far unidentified IOP spikes.

Test your IOP during the night for example, or at the gym, or while gardening, and in every other activity you participate in. If you find any IOP spikes, treat that issue and use EPOCT to verify that the progression has stopped.

All of this can take place in months rather than years, and you can connect the treatment with the results. This is why EPOCT is empowering.

Accessing EPOCT

EPOCT requires only a Heidelberg Spectralis OCT -- widely available in many clinics. However, implementing / accessing EPOCT in a typical clinic may still be challenging due to its specialized protocol. For those facing glaucoma progression, the effort to access EPOCT could be life-changing, just as self-tonometry has been for many of us.

But like the situation we faced with self-tonometry twenty years ago, you will likely have to convince your ophthalmologist to consider using the EPOCT protocol for you, and you may have to cover the costs of the extra OCT exams out of pocket (at least in the USA).