Prof. Anat Loewenstein, MD, shares the latest research on home optical coherence tomography in relation to reactivations and responses in retina patients during her presentation at the virtual Angiogenesis 2023 conference.
Editor’s note: This transcript has been edited for clarity.
Sheryl Stevenson, Group Editorial Director, Ophthalmology Times®: We're joined today by Prof. Anat Loewenstein at this year's Angiogenesis conference. Welcome to you. Could you please tell us a little bit about your talk this year?
Prof. Anat Loewenstein: Thank you very much. It's a pleasure to be part of the Angiogenesis 2023 and to hear and participate in all the big innovations that are coming up now in ophthalmology.
My talk is focusing on the Home OCT. However, it specifically emphasizes the characteristics of reactivations, responses and the connection between them as manufactured on the Home OCT. I think I already presented that the Home OCT basically really requires a lot of data from the B scans. In addition to the fact that it is performed by the patients at home daily, it accumulates a huge amount of data...really unprecedented insight available as such...in the dynamics of macular degeneration in their response to treatment and the need of treatment. For the patients that is to daily acquire the OCT and then the AI detects the fluid, provides the quantified spatial fluid thickness map, and also a trajectory that shows exactly what happens to the fluid over time with injections and while awaiting the next injection.
We looked at a few things and tried to see what are the potential implications and benefits of actually using Home OCT. We looked at 54 patients and from these patients, they had quite a large number: 35 reactivation and then 48 responses. Of them 35 reactivation treatment responses were manually also annotated. This actually was looked at and compared between the two. The starting point of the reactivations was identified by an expert grader, and I will show that there is a large variability in the increase of fluid rate, duration, and in the maximal fluid volume among reactivations, even in the same patient. The mean fluid increase rate was 12.6 nanoliters per day, the maximum was 116, and the mean duration of days from start to treatment was 12.
We could see some patients that had a very rapid increase in fluid volume. It has been shown both by the Home OCT and by the office OCT in a very comparable manner. There are patients where the huge rapid increase in volume to something like 700 nanoliter. This resulted in a lengthy response to treatment because their activation was so high, but we could see exactly when does fluid come down, and we could actually improve the patient's care. We also saw that there is great variability in the degrees of fluid and response and the duration of fluid volume until it resolves. So the minimal decrease rate was 8.3 nanoliters per day and the mean decrease percentage was 91%. Forty-size percent of responses and total fluid response in the meantime was 11 days.
You can really understand exactly what happens to the fluid following each injection. We considered 1 week as a practical desired response time to new information about reactivation and scheduling an office visit. We divided the patients into 2 groups by the time gap between the beginning of reactivation and treatment to more than 1 week and to less than 1 week. We saw the treatment after more than 1 week of fluid reappearance resulted in a huge difference in fluid volume treatment, an average of 10 days longer time to resolution, and an additional 700 nanoliter days of fluid exposure. We are showing some example of that of slower resolution and faster resolution as even more slow resolution after a longer delayed treatment.
This has very significant implications for patient care to show who is the responsive, who is the nonresponsive patient, who are the patients that benefit from a specific drug or from another drug. So a lot of data that shows us actually the personalized way we need to manage our patients with.
Stevenson: Excellent. Is there additional research that you're looking to do in this area?
Loewenstein: Of course. This is just the beginning...Some of them are sponsored by pharma that are going to show us what actually happens at the end with these differences in fluid exposure, how they translate to final visual acuity, number of visits and so forth, and many other implications and understandings that we can get from this huge amount of data.
Stevenson: Wonderful. We look forward to learning more about it in the coming months. Thank you so much for your time.
Loewenstein: Thank you.