FSH was FDA cleared for home monitoring in 2009. The AREDS2-HOME study compared visual acuity at the time of CNV diagnosis between 1,520 at-risk dry AMD patients who were randomized to the device plus standard of care (self-monitoring with Amsler grid and routine clinic visits) with a control group assigned to standard of care alone. Results demonstrated that among patients who tested with the device at least twice a week, 94% maintained visual acuity of 20/40 greater at diagnosis of wet AMD compared with 62% of eyes that used standard of care alone (P = .014).
The FSH relies on preferential hyperacuity perimetry (PHP). Hyperacuity is our ability as humans to perceive small differences in the relative spatial localization of two objects in space. During the FSH test, stimuli (a series of dots) are successively flashed in various locations along the central 14° of the macula. Most of the dots are aligned with each other and a few dots are intentionally misaligned, creating the perception of a wave or artificial distortion in an otherwise straight line.
If the patient has pathology, the retinal change (CNV) can cause a “competing” distortion. In this scenario, the patient will most likely perceive, and preferentially click, only the location of the greatest distortion. The algorithm recognizes if a patient clicks on the pathological distortion, isolates that area and then quantifies the distortion’s magnitude and location, comparing it to the patient’s baseline.
The FSH is designed to detect morphological changes in the macula that distort vision, including CNV. Other pathologies, however, such as vitreomacular traction, epiretinal membranes and drusen changes/remodeling can also distort vision and cause metamorphopsia. Therefore, not all alerts will lead to a CNV diagnosis. Suspected pathology must be confirmed promptly on a follow-up clinical examination with dilated eye exam, OCT and fluorescein angiogram. I look at a non-CNV alert as another opportunity for me to engage with my patients and reinforce their care. The rate of alerts in the real world is similar to what was observed in the HOME study, or about one alert per patient every 3.4 years.
Artificial intelligence and telemedicine
AI and telemedicine are poised to usher in massive changes in how health care is delivered. AI’s use in telemedicine can be seen in patient monitoring and intelligent assistance diagnosis as well as health care information technology, information analysis and collaboration, and simulation and training systems. AI and telemedicine are symbiotic, and together they can enable us to find diseases earlier, easier and cost-effectively.
By combining remote monitoring with machine learning, our standard of care will reach new and exciting heights and possibly even curtail health care costs. As a retinal specialist, it is truly an honor and privilege to be a leader in this field and be on the forefront of cutting-edge technologies to provide the best possible care for our patients.
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Disclosure: Mali reports he is a consultant, speaker and stock shareholder for Alimera Sciences, a consultant for and recipient of research funding from Allergan, a consultant and speaker for Genentech, a consultant, speaker and stock shareholder for and recipient of research funding from Regeneron, a consultant and speaker for and recipient of research funding from Notal Vision, a consultant and speaker for Sun Pharmaceutical Industries, and a consultant and speaker for Macular Degeneration Association.