ARVO 2024: Adjusting for pupil size in multifocal contact lenses

Video transcript

Editor’s note - The following transcript has been lightly edited for clarity.

Emily Kaiser Maharjan:
Hi everyone, I'm here with Dr. William Reindel, who is presenting a poster ARVO about the effect of pupil size on vision performance with use of a multifocal daily disposable contact lens. So thanks for joining me, Dr. Reindel.

William Reindel, OD:
Oh, you're welcome. Glad we could share some of the research we're presenting.

Kaiser Maharjan:
Of course. So first, can you tell me a little bit about how the study came to be?

Reindel:
Well, I think you know, one of the things that's important [is that] as we age, presbyopia affects quality of life in a variety of different ways. And so those of us that may be in presbyopia, we long for the days when we had pre-presbyopic eyes, that made natural changes in vision when we look at an object in distance, and then shift to an object at near [distance]. It's a very fluid system. So we look forward to those days, and we count on clinicians and researchers to come up with better options for the presbyopic patients to restore that dynamic vision that they once had.

Kaiser Maharjan:
Fantastic. And can you tell me a little bit, like just give me a topline summary of your poster, just to kind of give people context for what we're talking about.

Reindel:
Pupil size is so important, right? And we know that as we change our gaze from distance to near, pupil size can change as well. As well as higher order aberrations because the lens inside the eye is changing its shape to accommodate those different distances. Now, pupil sizes, [in] a large population of people, they can have a wide variety of different pupil sizes, right? So as they change gaze, their pupils get smaller, their aberrations can increase because the lens inside the eye is changing. And this can all be impacted by how much accommodative level we still have as we go through our journey of presbyopia. So we wanted to really understand the dynamics of optics in a multifocal lens. And, as I mentioned, people have a wide variety of pupils. So it's so important for us to make sure that the lens works well among that wide range of people who have different pupil sizes.

Kaiser Maharjan:
Yeah, absolutely. And can you walk me through some special considerations that must be made for fitting multifocal contact lenses when it in regards to pupil size?

Reindel:
Well, again, you know, it depends on the optics of the lens. So probably the most common lens is a center near design. So the multifocal add portion is in the center of the lens. And we all recognize that among consumers—and we get research from multifocal contact lens wearers—we know what drives satisfaction among this group. And those things are, they want the lens to be comfortable, but they also want to be able to see intermediate targets or objects, such as a computer that might be on their desk. They also, satisfaction is driven by near vision as well. So think about those consumers that, presbyopic consumers, that are looking at their mobile devices, and it's a little closer than their computer on the desk. So it's all of those things that are driving satisfaction. And again, pupil size is important because clinicians, practitioners, see patients with many different pupil sizes. So our optics have to accommodate all of those different pupil sizes. So that regardless of what your pupil size is, you're going to have great vision of near, intermediate, and distance objects.

Kaiser Maharjan:
Can you kind of give me the topline results in the satisfaction across all the pupil sizes that you found in this poster presentation?

Reindel:
Yeah. So first, let me give you an example of the sample size. So we have 293 subjects that were in this study. And their pupils ranged from 2 millimeters, when they were measured at the beginning of the study, to 7 mm. So you can see across that large population, there was a large number of different people with different pupil sizes. And the ages range from 40 years of age to 73. So again, we had a very wide range of individuals who had different demands on their accommodative system. So we divided our pupil sizes into 4 different categories, so that we can assess our data in those 4 different categories that went from category 1, which was the smaller pupils equal to or less than 3 mm. Category 2 was greater than 3 mm to 4 mm. Category 3 was greater than 4 mm to 5 mm, and then category 4 was greater than 5 mm. So again, you can see that we have a wide variety of pupil sizes.

So we looked at logMAR visual acuity, which is a very precise evaluation of visual acuity. And we found that there was no significant difference in terms of the logMAR visual acuity across those 4 different categories. So regardless of whether you had a small pupil, 3 mm or less, or a large pupil, greater than 5 mm, the visual acuity, the median visual acuity, was consistent for those categories. At distance, at intermediate, and at near. So we had a very good assessment of logMAR visual acuity, which is what the doctors really assess in the office.

We also asked the consumers, the patients, to give us feedback, a subjective rating of their vision at those 3 kind of distances. So they're really kind of assessing it over the course of the weeks that they wore the lens. It was a 3 week study; we had visits at 1 week and 3 weeks. So they were giving us feedback at week 1: How did the vision at near, intermediate, and distance perform? And how was the quality of their comfort as well? So we got a great assessment of what the subjective ratings from those consumers were as well.

And when we analyzed the median ratings, they were on zero to 100 scale with 100 being the most favorable, and the median values for near, intermediate, and distance were 90 to 100. So again, very high scores, and there was no significant difference in median scores between the category 1, 2, 3, or 4. And overall comfort was also on that scale, zero to 100, [with] 100, being the most favorable, and the median scores, were also greater than 90 in all of those different pupil sizes. So we were really excited about the results because it really highlighted that the lens design, this 3-zone progressive lens design, was capable of delivering quality vision for subjects, regardless of their pupil size, as well as comfort, which is also important when we do our assessment. What drives satisfaction among multifocal contact lens wearers?

Kaiser Maharjan:
Yeah, absolutely. I mean, even if, you know, your numbers are off the charts, if the patient is uncomfortable, then you know, they're not going to wear them and it's not gonna work.

Reindel:
That's right, yeah. They always say comfort is king, which is very important, but vision is too for the presbyopic population because they're kind of losing their ability to accommodate as they go through their presbyopic journey. So vision is very important. And that's why we saw key drivers of satisfaction where we saw intermediate and near vision, were also very important in ultimately, the satisfaction of the performance of a multifocal contact lens.

Kaiser Maharjan:
Yeah, absolutely. And could you give me a few key takeaways from the study?

Reindel:
Well, I think the one of the keys is, you know, ultimately, the patients, right? Their experience with them. They had high levels of logMAR visual acuity as well as the vision at those 3 distances: distance, intermediate, and near, but also the benefit of what it means to practitioners, right? Because ultimately, the practitioners want to have a high level of satisfaction among their wearers. And so it really highlighted that regardless of the pupil size, the lens really kind of delivers. And that's kind of one of those nagging questions among clinicians is: What happens with my patients that might have a smaller pupil size than a larger pupil size when they're wearing a center near multifocal lens? So this really highlighted the fact that clinicians will have great results as well as their contact lens wearers.

Kaiser Maharjan:
Fantastic. And is there anything else that you want to mention that we haven't touched on?

Reindel:
I think, again, that we all have to be cognizant of some of the challenges that presbyopic patients go through, right? Regardless of our age, as clinicians, we have to know that what are the factors that contributed to contact lens success, and how sophisticated some of the multifocal lenses have become when they take into account these various things such as pupil size, higher-order aberrations, and residual accommodation.

Kaiser Maharjan:
All right, well fantastic. Thank you again for taking the time to chat with me, Dr. Reindel. I really appreciate it.

Reindel:
It's my pleasure, Emily. Great to chat with you as well.