The Growing Glaucoma Burden: New Approaches to Treatment
Mark Dlugoss:
Now, one of the newest things in treating glaucoma has been corneal hysteresis. Am I pronounced that right, hysteresis? And can you explain the role of corneal hysteresis in treating glaucoma?
Dr. Jessica Steen:
When we talk about corneal hysteresis, we’re talking about the cornea’s ability to be able to dampen a force. What the thought here is, is that as the cornea, as an extension of the sclera, extends to make up the lamina cribrosa tissue all as mesodermal tissue, the reflection of that cornea’s ability to dampen a force might be reflective of the lamina cribrosa’s ability to dampen a force, or that backward bowing that often we have, from a really fine technical level, in elevated intraocular pressure.
Now what happens is that as the lamina cribrosa shifts, and bows backwards, the axons that pass through it become sheered, and stressed, and damaged, which then precipitates a further inflammatory damage of that tissue and axonal damage.
So what the thought is, is that if we can measure this corneal hysteresis, the ability to dampen the force of the front of the eye, it should be reflective of the lamina cribrosa’s ability to dampen a force at the back of the eye. So the stronger the ability of the cornea to dampen that force, may be the stronger the ability of the lamina cribrosa, or the weaker the cornea’s ability, the weaker the lamina cribrosa’s ability. Meaning that, eyes with low corneal hysteresis do have an increased risk of the development of glaucoma, as well as the progression of glaucoma. So, this is really an additional biomarker, that is an estimate of the function of another part of the eye and another tissue, but certainly, something that we do understand its relevance. It’s one more risk factor to consider.
Mark Dlugoss:
Okay. Well before we move on, let’s, are there any pearls that you can share with our viewers in regard to diagnosis and treatment of glaucoma?
Dr. Jessica Steen:
Take your time. So, we often feel the pressure to come up with an answer for the patients who have a diagnosis of glaucoma suspect. We try to answer that question, does the eye have glaucoma? Yes, or no? And I think our biggest lesson is that we understand that we can’t answer that question in many individuals on a single visit, or even short term. Take the time that you need to gather the data that is going to be most relevant, for you to make that assessment and appropriate evaluation. We certainly never make a decision based on one intraocular pressure measurement or one visual field. So, take the time that you need, to appropriately and truly understand that patient’s overall risk.
Mark Dlugoss:
Good advice. Now move on to technical innovations in glaucoma. And this includes diagnostic equipment and pharmaceuticals if not. What are your impressions of the technological advancements that have occurred in the last 10 years regarding glaucoma?
Dr. Jessica Steen:
Well, when we talk about diagnosis within the OCT space, certainly, we’ve seen significant development with faster scanning speeds, a shift towards swept-source technology, which is excellent for evaluating deep tissues including the lamina cribrosa. Most recently within OCT, we’re working with spectral domain high resolution imaging. So, this is not swept-source technology, its spectral domain technology, but allows for a higher axial resolution, which is really, the driver here is the retinal space. But certainly, something interesting from an optic nerve evaluation perspective as well. OCT angiography, certainly technology, normative database comparison, and evaluation of change over time, is something that continues to develop, and have clinical relevance. Within glaucoma, again, this is really one more risk factor that we understand, and one more metric that may be incorporated. Although from a clinical perspective, sometimes, we’re not so sure as to what some of these biomarkers or results may mean, following the patient over time and watching for change. I think that OCT angiography is an important metric in the management of glaucoma.
When we talk about visual fields, we’ve certainly seen huge technological advancements, and the shift ultimately to in the patient’s home ultimately, as well as these types of virtual fields. So, utilizing technology that is a virtual reality type of device, rather than that standalone Humphrey type visual field, or others, Octopus visual field. Now there are some challenges with these virtual reality types of visual fields, primarily engineering challenges from a true technical aspect. In our clinic, we certainly do utilize the Humphrey visual field for all of our patients. I am not incorporating virtual field technology at this point. And one of our really important understanding pieces here, is that we’re managing and monitoring patients over a period of many years. So that data that we have from 1995, 2000, 2005, 2010, and so on, is so valuable in this patient’s disease course, from a chronic disease management perspective. So, I really need, from a management side, that long-term data, which, if we switch to another platform, we don’t have direct incorporation or integration of that data as well. So, I truly do rely on our in-office perimeter.
We have also had the development of new testing strategies. For example, the incorporation of an additional 10 points in the paracentral visual field area, to detect this paracentral damage more effectively, than with our typical 24-2 parameter of a visual field. So there are advancements in our diagnostics.
From a therapeutic perspective, certainly in the last 10 years, we have had new classes of medications being developed, Rho-kinase inhibitors, our understanding of the importance of enhancing trabecular meshwork outflow is certainly key. And then most recently, with omidenepag isopropyl, a non-prostaglandin, EP2 receptoragonist. Once again, a new mechanism of action to lower intraocular pressure.
Mark Dlugoss:
You’ve covered a lot of ground right there. How has the innovation improved? Taking it from the clinic clinician’s perspective, how has the innovation improved the clinician’s ability to diagnose and treat glaucoma?
Dr. Jessica Steen:
If we really jump to treatment, we understand that every patient is so different. There are, not only personal preferences, but individual responses to particular treatments. So where we are in 2023, with different options to apply and to prescribe, or to recommend for different patients is really the key. It allows us to truly tailor that treatment to an individual’s needs. And needs as well as wishes, which can be medical therapy, laser-based therapy, or collaboration for consideration of incisional therapy as well.
Mark Dlugoss:
There’s a lot of technology, it keeps evolving and evolving. What new items, in the last year or so, has really gotten you excited about the technology, in terms of diagnosing glaucoma?
Dr. Jessica Steen:
The continued advancements within OCT. Now, I think, every major manufacturer of an OCT device understands very well the limitations of normative databases that we have. We understand that that person who’s sitting in front of us, very well may not be reflected within a device’s normative database. And understanding, applying, developing, really patient specific, or individual or group specific, types of normative databases is something that really is important, to allow us, as a clinician, to compare our patient to a like group of individuals. Really, the greatest example here, is speaking about the development of normative databases of highly myopic individuals, whom we know can be very challenging, to determine the development or change due to glaucoma, based on difficulties in imaging and optic disc appearance as well. But certainly, an important group, as a high myop myself, to understand that they are, we are, at a significantly increased risk of developing glaucoma long-term.
Mark Dlugoss:
Part of the progression of innovation is artificial intelligence. What are your perceptions of artificial intelligence?
Dr. Jessica Steen:
Artificial intelligence in the management and detection of glaucoma certainly is a very, very sweet spot for me. This is our research group’s heart and soul, and certainly, a very specific interest of mine also. What we are truly most interested in, at this point, is opening the ability for additional research groups, clinicians and scientists, to best evaluate and study the impact of artificial intelligence in glaucoma diagnosis.
I will say, one of the challenges in these high technology fields is that, there can often be very limited data, that is often proprietary and owned by a private institution, and unable to be shared well amongst the community. This has been really the push behind something that we call federated AI, the ability to test a particular model on a proprietary dataset. A group of, for example, images that may be used to train or analyze the ability of an artificial intelligence model, for example, to detect glaucoma based on a fundus photo.
What our group’s current interest is, is developing large high quality publicly available data sets, so that individuals, potentially at smaller institutions, or smaller facilities, have access to these really high quality, well evaluated and analyzed data, where, right now, currently, it’s very challenging for researchers.
So really, the bigger picture, from a clinical side, of incorporation of artificial intelligence is to, number one, potentially find patterns that we are not, as an individual, able to detect. So this incorporation of big data, and sifting through thousands, or hundreds of thousands, of data points, to understand potentially new markers of risk of disease development or progression, as well as incorporating artificial intelligence into workflow platforms. So how do we schedule patients back in our services? Who are those highest risk individuals? And are there features that can, for example, bump them to the top of our workflow pattern, in refilling a medication prescription, or understanding the optimal interval between OCT testing for a particular patient, between visual field tests for a patient, or even office visits? I think it’s about optimizing really, the clinical flow in clinical care, and understanding that from an individual clinician’s evaluation of a patient, there are many points that artificial intelligence models certainly will and can detect, that we are unable to see.
Mark Dlugoss:
So where do you see the role of the optometrist and the clinician in working with artificial intelligence?
Dr. Jessica Steen:
I think the shift here is that, we very well may become more centrally involved in interpretation, and evaluation of risk profiles that may be generated by incorporating testing features by an artificial intelligence model. And then, discussing and counseling the patient on the potential risk, advantages, disadvantages, of a particular treatment. So still maintaining that very humanistic and interpersonal aspect, that we know that our patients truly do seek, and care, and appreciate, but to have help in the decision-making process. And we’ve talked about new metrics that become available. How do we make sense of all of these metrics, while incorporation and help from, for example, an artificial intelligence model, certainly is something that would improve our ability to sift through those individual data points in an individual circumstance.
Mark Dlugoss:
Another technological advance which is getting a lot of play lately is workflow systems. Are you utilizing a workflow system in your practice to manage patients? And can you outline some of the features of a workflow system that make your job a lot easier as a clinician?
Dr. Jessica Steen:
So, the workflow system that we utilize at Nova Southeastern University is FORUM, which is one of the most well-developed and established systems. So, what this allows me to do is, I’m able to, number one, when we have patients who have been existing patients of our service for the last 20, 25 years, I’m able to very easily navigate through each visual field that that patient has performed over time. And nevermind incorporating or evaluating the individual fields, but more importantly, able to look at the data of these visual fields in a long-term progression analysis, so we can understand very quickly, what the long-term trend of an individual is. If we identify progression, and alter change or escalate therapy, we can very easily adjust or set a dual baseline in the visual field analysis, to understand and really, truly appreciate now, the trend or the change that we may expect long term with visual field, hopefully, stabilization.
The other real advantage that we have is, to easily incorporate the structural and functional information truly onto the same page, to very quickly, very easily understand that, if a new three-point region, that’s abnormal on a 24-2 visual field, may pop up, does that correlate with the optic disc appearance? Does that correlate with the retinal nerve fiber layer analysis and ganglion cell plexiform layer analysis, or is that area more likely to be artifact, or a difficult field day for the patient? So it’s again about making it more, increasing the clinician’s ability to really evaluate pieces of data simultaneously, and to compare and to incorporate each data point into one other.
I will say, one of our challenges is that, our workplace system is not directly integrated with our electronic healthcare record. So we do still have these two types of panels that we do need to be assessing and addressing, but certainly, any workplace workflow type of program certainly has improved our care of patients with glaucoma, especially, to really sift through these large amounts of data.
Mark Dlugoss:
How has the workforce system helped you and your practice in basically, monitoring? Has it made it easier? How do you work with it in dealing with patients?
Dr. Jessica Steen:
It’s improved my efficiency. Which for something to be in a clinical environment, anything that optimizes or improves efficiency is certainly a key takeaway and key keeper. So how I will, and how I have today, incorporated FORUM into our evaluation, is for individuals who had a visual field test performed today. I can now easily look at, not only today’s visual field test, but also the trend in that visual field over time. Is there gradual change that we have detected? Or through guided progression analysis, potential clinical change that’s been detected? And I can compare that patient’s visual field to the OCT based data on a single page for myself, to again, improve the efficiency and understanding, and potentially, making those connections, whether they are true clinical disease progression related connections, or to more effectively evaluate whether that concern of change is more likely to be artifact, or a poor testing day, or just a subtle eye movement.
Mark Dlugoss:
Amazing what the technology is going to do. One of these days, it’ll be a lot easier to just be able to, one picture and grab it all, and have it all done, and make your job a lot easier. Especially if more and more patients coming down with glaucoma.
Dr. Jessica Steen:
Which really means, that we can spend more time with the person in the room, counseling, discussing best options, and really playing that central role, to try to really maximize the understanding of the disease process, and long-term care needs as well.
Mark Dlugoss:
Let’s move on to a new paradigm that’s coming into glaucoma, and that’s interventional glaucoma. Can you explain the concept of interventional glaucoma? Well actually, it’s been around a long time, but it’s only been in the last three to five years, it’s really sort of gotten some legs and starting to make moving. The concept is merging as a more of a proactive, as opposed, a paradigm, as to a reactive approach to treating glaucoma. Can you align the emerging concept of interventional glaucoma?
Dr. Jessica Steen:
Sure. So interventional glaucoma, or procedure-based treatments in the management of glaucoma, as you said, certainly aren’t new. However, with improved safety profiles, that is the big one here, we are seeing this continued push for interventional management earlier in the disease process, to try to prevent those progressive events from occurring. Now certainly, there are challenges from a regulatory standpoint in clinical trial design, in looking at interventional based specific procedures much earlier in the disease course. That is an ongoing really unmet need, to advance the regulatory questions, and clinical trial design here, to best reflect a current clinical situation. But certainly, with the rise of MIGS procedures, and procedure-based therapeutic options, we’re certainly, again, at a time where every patient who comes to see us, has certainly more than one avenue to effectively, appropriately, and individually, treat their disease process.
Mark Dlugoss:
What are your perspectives of this new paradigm shift of interventional glaucoma? Do you see a positive light to it?
Dr. Jessica Steen:
Certainly, it is only positive. So any type of treatment that acts, or attempts to prevent or delay disease progression, especially early on in the disease process, is outstanding. The challenge that we have in glaucoma when we speak about early disease, we’re talking asymptomatic disease. And it can be very challenging for an individual to think about 10, 15, 20 years down the future, down the road, and what functional challenges may develop, due to disease progression, when at this point in time, sure, their pressure’s 35, but their vision is excellent, and their field may be very clear or clean as well. So that’s I think, our biggest challenge in a patient discussion standpoint. That thinking about the future in an asymptomatic, in early stages chronic disease, can be very challenging for an individual to truly do, for any individual to truly appreciate.
Mark Dlugoss:
What role do you see the optometrist playing in interventional glaucoma?
Dr. Jessica Steen:
So certainly, we are closely co-managing these patients, and discussing and identifying the individuals that very well may benefit from an alternative or additional mode of treatment.
Now often, these may be patients even that are newly diagnosed with glaucoma, that may have been patients in our practice, or our family’s practice, for many years. So the relationship that has developed over that multi-year career, between the optometrist and the patient, is very valued by the patient. And understanding and really quarterbacking the potential next steps is something that’s really key. From our perspective then, communication with the provider that we are referring to is so central. Understanding that patient’s disease history, their previous, for example, experience with additional medical therapy, or additional procedures, and really, what their long-term disease course has been. Is this somebody who is stable, with an intraocular pressure of 12 millimeters mercury on one topical medication over time? Or is this an individual that’s shown progression, with a consistent intraocular pressure of 15 on three medications, who really is not able to tolerate an additional topical medication? That history, that understanding that story, is so important for co-managing providers to really provide, because that truly does help to shape the understanding of the next steps that may be an option, as determined by the consulting physician on that case.
Mark Dlugoss:
Do you think interventional glaucoma improves the co-management relationship with ophthalmologists?
Dr. Jessica Steen:
I do. Because certainly, it really is centered in communication. So we get to know our managing and co-managing providers really, on a much closer level. We’re speaking about the same cases, we’re discussing, maybe small features, whether that’s over the phone, or expressing ourselves in writing very clearly and concisely. And ultimately, from a patient perspective, they truly really do appreciate when doctors are working on the same team for their betterment. So this ultimately, I think, has really, really advanced, not only patient care, but truly, how we work together as a community, and really with that ultimate goal of providing better care.
Mark Dlugoss:
When it comes to clinical information about glaucoma, we’ve only touched a tip of an iceberg today, of a very large iceberg by then. Are there any final thoughts, or advice you’d like to share with optometrists about proactively treating glaucoma?
Dr. Jessica Steen:
I think one of our big takeaways, especially as we’re discussing technology, new therapeutics, new advancements, we all are very excited about what we have and what’s to come. But really, we do need to back up and remind ourselves, that no one test can diagnose disease. It’s really about the clinician’s good clinical experience and clinical acumen, that drives that understanding, that conversation, and that long-term successful disease process.
Mark Dlugoss:
Dr. Steen, thank you very much for joining me and talking about glaucoma today. I appreciate it.
Dr. Jessica Steen:
Mark, thank you. My pleasure.
