Q&A: Andreas Pollreisz explains when to use and not use widefield OCT-A imaging

Photo of Andreas Pollreisz at the 2025 EURETINA meeting in Paris, France

Andreas Pollreisz, MD, a medical and surgical retina specialist from the Medical University of Vienna, discussed widefield OCT-A imaging at the 2025 EURETINA meeting in Paris, France. He explored its potential in diagnosing diabetic patients, highlighting the technology's ability to non-invasively image the retina. While current limitations exist in field of view, Pollreisz predicted future improvements and emphasized the continued importance of multimodal imaging and AI analysis tools in understanding complex retinal changes.

Note: The following conversation has been lightly edited for clarity.

Ophthalmology Times: You are presenting at the EURETINA 2025 meeting. What is your presentation discussing?

Andreas Pollreisz, MD: I just talked about widefield OCT-A imaging, which is a pretty novel technology, but a technology which will become quite important in the next years to come. Why? Because diabetic patients are quite challenging to diagnose and also quite challenging to follow up over time. Because the problem is that when we look at patients with dilated fundus examination or with, let's say, widefield color fundus photography, the fundus in the retina might look quite unremarkable while there is already significant damage present.

So OCT angiography is a novel methodology which allows us to image the retina, non-invasively, within a couple of seconds. However, so far, the drawback was the field of view. You could just image quite a small area, and this obviously limits its application. So for instance, when we want to differentiate neovascularizations from intraretina microvascular abnormalities, or if you want to detect the extent of retinal ischemia, fluorescene angiography is still our gold standard.

OT: Will widefield OCT-A replacing our fluorescene angiography

Pollreisz: So if you ask me, is widefield OCT-A replacing our fluorescene angiography, at the moment, I would say not really, because we need the widefield assessment. And so how I approach it at the moment is that I use widefield fluorescence angiography as the kind of first examination to see where damage is present in the retina, and then I can follow these areas using widefield OCT-A, which obviously, at the moment, does not reach the areas that I would like like to see in which I see with ultrawidefield fluorescence angiography. However, in the years to come, I see that in widefield, OCT-A the field of view will extend, and I think then we might have the chance that OCT-A will replace fluorescence angiography when analyzing peripheral areas.

OT: Why is imaging the retinal periphery of diabetic patients so important?

Pollreisz: So imaging the retinal periphery in diabetic patients is important because the macula does not reflect damages that seen in the periphery, and this has been known since quite a long time through a lot of imaging studies. So having an imaging modality available that detects peripheral areas as well as central areas is very important. Another important thing is to have an imaging modality available that's easy to use, that's fast to use, and it's also not doing any harm to the patient. For that, widefield, OCT-A is an attractive opportunity to use in these patients, which might have impaired kidney function or maybe a vein status, which is not so easy to get the fluorescent dye injected. So OCT angiography would be an ideal examination technique in these patients.

However, the field of view currently is a limitation. 10 years from now, multimodal imaging will still be something that we are using, particularly in combination with AI analysis tools, because we need AI in order to combine all these imaging technologies, particularly in diabetic patients, where you have so many changes ongoing. So you have ischemia, you have neurovascularization, and you have diabetic macular edema in the center. So you need to image the whole retina, and by combining different modalities, I think that's quite a good way of how to approach these patients, because there are limitations to all of these technologies, right?

So for instance, when there is vitreous hemorrhage, present at least some remnants of vitreous hemorrhage present, then OCT angiography might not be the best choice. And in these cases, for instance, fluorescence angiography, even 10 years from now on, will be the right choice. So I think we need to keep our tools. We don't have to replace them, but a multi-modal imaging approach, I think, is something that in 10 years from now will still be in our toolkit.