Visual field testing undergoes modern transformation via wearable technology

Image Credit: AdobeStock/Mangostar

For the past 3 decades, visual field testing has remained relatively stagnant, with the bowl perimeter occupying a central role in the examination rooms of eye care providers worldwide. Despite advancements in various fields, this cornerstone technology has seen little innovation. However, recent breakthroughs in microdisplays, battery longevity, and wearable devices have sparked a revolution in visual diagnostics. Among these is Radius XR, which offers a wearable, mobile headset and a diagnostic platform that combines accuracy, efficiency, portability, and patient comfort.

Notably, Radius XR‘s recent achievement, which was featured in the Association for Research in Vision and Ophthalmology’s Translational Vision Science and Technology (TVST) journal,¹ underscores its advantages compared with other headset-based virtual reality perimeters on the market. The study revealed statistical noninferiority to current clinical standards for sensitivities at individual test locations, statistical noninferiority in glaucoma staging using Medicare definitions, and a high correlation of 0.94 in mean deviation (MD). It is also important to note that, unlike with other perimeters, the background luminance of this platform measures vision within the photopic range, which is the standard within existing visual field platforms. This allows for consistent clinical training and comparison to patients’ prior examinations, as normative databases and MD/pattern standard deviation plots are based on the photopic range. (Complete details regarding the clinical study are found in the associated supplement.)

My journey to integrating this platform began similarly to that of many of my colleagues. Our practice’s older bowl perimeters started to break down, and we were confronted with costly repair quotes, travel, and downtime when contacting the manufacturer for repair. Furthermore, we learned that our units had been made obsolete, leaving us with the only option to buy a new tabletop device. Meanwhile, our patients continued to express angst and dissatisfaction with the repeated exams. Buy-in for a new platform came quickly from 2 key constituency groups: staff and patients. Both groups were on board quickly as we implemented Radius XR testing in our 4 centers throughout Sonoma County, California. What follows are a few pearls of what to expect when introducing this technology into your practice, with specific examples of how it can provide an enhanced experience for both staff and patients.

Steve R. Sarkisian Jr, MD (center), and Kelsey O’Neil, diagnostics regional business manager, South, at Glaukos Corporation, after a successful implementation visit with Brian Murphey, global vice president of sales, Radius XR.

The portable vision diagnostic and patient engagement system combines medical-grade hardware and patient education tools in a wearable spatial computing device. It provides a patient-guided exam process through a comfortable, user-friendly, lightweight (6 oz), medical-grade headset (Figure 1). The system can be used for early detection as a screening device and as part of one’s glaucoma management strategy by monitoring progression using traditional threshold testing strategies, thereby effectively combining 2 legacy machines.

My colleagues and I run a busy multispecialty practice, and we all love the streamlined and efficient workflow integration. As a glaucoma specialist, it is essential that I can count on a testing capability comparable to the standard of care. With the help of multiple colleagues around the United States and Radius XR’s chief vision scientist, Chris Bradley, PhD—research associate at the Wilmer Eye Institute at Johns Hopkins University School of Medicine in Baltimore, Maryland—the aforementioned validation study published in TVST,¹ which is summarized in the attached supplement, demonstrated parity from a statistical and clinical approach.

Unlike other repurposed gaming headsets on the market, the Radius XR is a purpose-built, medical-grade precision instrument. In conjunction with the hardware, the perimetry module is poised to become the new standard of care. Although the adoption of Radius XR continues to grow around the western hemisphere, the company’s core values and goals remain at the forefront: listening to customers’ feedback, facilitating regular clinical updates with new exams, and growing the library of educational videos from world-class specialists and key opinion leaders (KOLs).

Radius XR continues to invest in scientific validation. At this writing, multiple clinical trials are ongoing at premier teaching institutions and private practices around the United States, and novel validated progression analysis software is on the way. The scientific rigor in developing the platform and an open-science approach in implementing over-the-air updates ensure this multifaceted tool will continue to evolve as an indispensable device for best-in-class patient care.

From the minute the patient checks in, the front staff can start the experience with a Radius XR unit. For example, we could start with a “welcome to the practice” video that introduces the practice and the doctor the patient will see. We then could run the visual field test before the patient returned for the clinical intake workup. This single change in protocol has improved the flow of my practice, especially on days with 50 to 60 patients flowing through the clinic. Our clinic’s secret sauce includes me seeing follow-up patients only once during their journey in the office, or twice (pre- and post dilation) for a new glaucoma evaluation. This streamlining necessitates having all the ancillary data available for me to review at the encounter. For this to happen, we generally perform the visual field testing up front, prior to patients going into the exam lane, and then have them watch an educational video in the headset while waiting to see me.

Figure 2 of 3.Two of my North Bay Eye Associates patients taking the Radius XR visual field test (left, in a dilating area; right, in the waiting room).

Completing visual fields before patients enter the exam lane allows us to keep those exam lanes available, which otherwise can be a rate-limiting factor to patient flow. How you integrate the technology into your own clinic’s workflow may differ; the flexibility of where, when, and how you use it in your practice is up to you. Staff and patients can engage with the platform in a lane, in the waiting room, or in the dilating area without needing a dedicated space or room (Figures 2 and 3).

Figure 3 of 3.Two of my North Bay Eye Associates patients taking the Radius XR visual field test (left, in a dilating area; right, in the waiting room).

In addition, the ability to provide basic information through the headset allows for more substantive conversation when you discuss a condition or a proposed treatment option with the patient. For example, having a video available in the video library of yourself or one of the KOLs explaining a novel therapeutic option like travoprost intracameral implant (iDose TR; Glaukos) or a microinvasive implant (iStent infinite; Glaukos) while the patient undergoes pupil dilation saves a substantial amount of
time. It also jump-starts the informed consent process, as patients can ask more educated and focused questions during your time together.

Making a personalized video is simple. For example, you could create an educational posterior vitreous detachment (PVD) video. That way, when an emergency patient with a PVD walks through the door at 5 pm, the condition can be explained with an educational video while the patient is dilating. Meanwhile, I can use that extra time to quickly catch up on my emails and other end-of-the-day tasks rather than giving a tired explanation of the situation.

I’ve found that patients are pleased when we run visual fields with the platform—and happy patients make for happy staff. Additionally, some doctors are now implementing out-of-office testing, including tonometry and visual fields, then reviewing the results with a virtual visit. Remote patient monitoring codes are now available, making this model financially viable for practices.

Figure 4. North Bay Eye Associates’ lead diagnostic technician Vanessa Mann demonstrates the ability to initiate and monitor 2 tests simultaneously.

(All photos courtesy of Jason Bacharach, MD.)

Another benefit is that a less-seasoned technician can administer the testing or start the educational videos for the patient. For Humphrey visual fields, there can be a learning curve for technicians to understand the innuendos of positioning, monitoring, and encouragement. In contrast, the learning curve for technicians is swift for the unit. Once technicians become facile, they can run multiple tests simultaneously (Figure 4). The system’s in-clinic dashboard allows them to monitor, control, and observe the live status of all devices within the clinic. Indeed, for our staff and clinic workflow, the adoption of Radius XR has been a major step forward.

For the patient, headset-based visual field tests have also been a game changer. A visual field machine tucked into a dark field room has traditionally been a mainstay in most offices. These rooms tend to be confined to save floor space, and they usually require a walk to take the test. Some practices even have the field machine in a separate office, requiring the patient to transit between offices regardless of the weather outside. This means that patients with mobility issues must navigate to the field machine as well as into the field machine. In turn, test results are invariably less reliable if the patient is not comfortable. False negatives or positives, fixation losses, or rim artifacts (eg, due to the patient falling back from the mounted lens in the unit) are common. There also can be an intimidation factor for patients when required to place their heads into an antiquated contraption like a bowl perimeter. Many patients are claustrophobic, which can further compromise the test.

Lastly, the COVID-19 pandemic has highlighted the importance of good practice hygiene, and cleaning bowl perimeters can be a significant issue. Cleaning can damage the bowl’s surface, rendering the background luminance imperfect and permanently damaged; patients also have questioned the sterility of the environment. In contrast, this novel portable vision system has a replaceable biocompatible light seal that encounters the patient’s skin and can be replaced between patients or sterilized using standard cleaning protocols. Instead of seeing social media posts about wait times and cumbersome visual field tests, we see posts of patients smiling with the goggles on, stating how fantastic their experience was in the office.

All in all, the enthusiasm and buy-in of the key constituents of staff and patients have been tremendous. From ease and flexibility of scheduling visual fields to the reduction of clinical bottlenecks in the practice, we could not fathom returning to routine use of fixed bowl perimetry. The patients at North Bay Eye Associates love using the headset. It provides an immersive experience, transporting them out of the hustle and bustle of a busy practice setting and into a personalized, educational, ergonomically comfortable visual field platform with dependable gold-standard accuracy I can trust.

Reference:

1. Bradley C, Ahmed IIK, Samuelson TW, et al. Validation of a wearable virtual reality perimeter for glaucoma staging, The NOVA Trial: Novel virtual reality field assessment. Transl Vis Sci Technol. 2024;13(3):10. doi:10.1167/tvst.13.3.10