The coronavirus disease–2019 (COVID-19) pandemic introduced unprecedented obstacles in the care of retinal diseases, including reduced access to screening, monitoring, and direct medical/surgical intervention. Amidst the global emergency, large advancements in ophthalmic models of care were expedited and widely adopted to address the new onset of barriers to essential eye care. Within the field of retina, telemedicine and self-monitoring technology provided innovative solutions for patients and providers while taking into account public health safety. These advances include optimizing patient triage with telescreening and at-home monitoring of vision impairment with mobile devices.1–3 These robust advancements also offer optimized workflow and technology for care of retinal diseases following the pandemic. In this article we review longstanding, practical changes that are likely to become integrated into the standard retinal models of care in the post–COVID-19 era. We also discuss future implications from this accelerated rise of retinal telehealth including artificial intelligence, Internet of Things (IoT), and blockchain cybersecurity for increased health data transfer (Fig. 1).
A literature search was conducted for this article to concisely review digital advances in retina that have been developed/highlighted during the COVID-19 pandemic that have practical applications for the future standard of care. This literature search occurred between July 2021 and August 2021 and was conducted to identify articles within the scholarly databases of PubMed and ScienceDirect. Search terms included “Retina”; “Telemedicine”; “COVID-19”; “Virtual Clinic”; “Tele-ophthalmology”; “Ophthalmology”; “Mobile App”; “Vision Assessment”; “At-home Screening”; “Monitoring”; “Virtual Reality”; “Optical Coherence Tomography”; “Blockchain”; “Internet of Things”; “Artificial Intelligence”; “Machine Learning”; “Digital Advances”; “Triage”; “Lockdown”; “Pandemic”; “Diabetic Retinopathy”; “Age-related Macular Degeneration.” These individual terms were searched either independently or combined to form the scholarly search for this article.
Retina and Telemedicine During COVID-19
At the onset of the COVID-19 outbreak, there was an immediate need for a system to triage ophthalmic patients based on severity to effectively manage resources and reduce burden load.4 Prior to the pandemic, telecommunication in ophthalmology commonly took place through the “Store-and-Forward” technique, an asynchronous mode of communication where information (eg, retina image) was sent and reviewed later.5 As in-person clinic visits became limited, synchronous, bi-directional teleophthalmology appointments became more common and implementation of telescreening allowed for effective triaging for in-person visits.5,6 Chen and colleagues reported that nearly all patients at an eye emergency service who underwent a novel teleophthalmology triage system during COVID-19 expressed high levels of satisfaction when asked about immediate access for advice, waiting times, and reduction of COVID-19 exposure. The study also reported an average reduction of 43 minutes from arrival to treatment, and >1% of triage decisions were deemed inappropriately managed.6 Retina emergencies such as retinal detachment often require emergent retina specialist evaluation and surgery to prevent permanent vision loss. The implementation of telescreening for ocular emergencies as seen during the COVID-19 outbreak appears to be an effective method for reducing time to care, thus, seemingly advantageous for retinal emergencies requiring immediate intervention. In addition to efficient care, the high levels of patient satisfaction reported by Chen et al6 are encouraging for deploying this digital model of care in the post–COVID-19 era. Additional studies may be helpful to further optimize and validate the implementation of telescreening for retinal emergencies.
Retina and Ocular Imaging–Based Models of Care During COVID-19
One of the major limitations of telemedicine in retina is the need to obtain anatomical evaluation of the macular and retina to make treatment decisions. Prepandemic, various institutions have already developed imaging-based “virtual” clinics, with asynchronous review of imaging results and telemedicine-based communication of findings to patients.7–9 These virtual imaging clinics often deploy optical coherence tomography (OCT) with standard or ultra-widefield fundus photography to provide the imaging input required to manage diseases from diabetic retinopathy and macular edema to age-related macular degeneration (AMD). Although these imaging clinics still require the patient to travel out of their homes for imaging, it has the potential to reduce crowding and waiting times in hospitals thereby improving social distancing and reducing the risk of infection. In addition, health care systems can potentially site these imaging centers in the community, reducing the travel requirements for patients.10,11 As such the adoption of these ocular imaging–based models of care have accelerated during the COVID-19 pandemic. In the Singapore National Eye Centre experience, our virtual imaging retina observation clinics had good patient satisfaction and reduced patients during overtime by more than 50% (Fig. 2). The introduction of mobile app–based visual acuity test which patients can perform at–home can further reduce the time in clinic, and potentially enable more effective telemedicine consultation in retina.
Retina and At-Home Monitoring and Screening
During the pandemic lockdown, patients with pre-existing retinal diseases faced a disruption in their routine monitoring.12 Optimal monitoring of retinal diseases typically requires in-person visits with a retina specialist which was largely attenuated during the pandemic. However, digital technology allowed for the remote monitoring for patients scheduled for retina clinic visits during the lockdown period.11,12 Teo et al12 reported the deployment of a mobile phone application (Alleye) for retina patients to self-monitor their retinal health to identify pathologic macular features. The Alleye application gave accessible instructions and alignment hyperacuity tasks for patients to complete on their mobile device to test the macula and related visual function.11 Patient diagnoses in the study included neovascular/non-neovascular AMD, diabetic retinopathy, diabetic macular edema, and retinal vein occlusions. Patients with poorer visual acuity were found to have increased participation and the mobile application was able to detect disease progression or reactivation in 5 patients (1.6%). The authors of the study concluded that self-monitoring for pre-existing retinal diseases demonstrates promise in the post–COVID-19 era.12 Self-visual acuity testing on mobile devices was also utilized and studied during the pandemic.13 Samanta et al13 reported that Peek Acuity, a smartphone application, did not perform worse than Snellen charts. In addition to mobile device monitoring, wearable digital technology was utilized during COVID-19, including oculokinetic perimetry for visual field testing with virtual reality technology.14 The pandemic also highlighted pre-existing, at-home monitoring technology, such as Notal Vision Home OCT to monitor exudative AMD.11 This technology combines at-home monitoring with artificial intelligence technology to monitor and map intraretinal and subretinal fluid.15 Notal Vision also has a home monitoring device called ForeseeHome, which allows for daily testing of patients with intermediate AMD. The device has patients interact with a clicker to map out visual distortions; results that deviate from baseline are sent to the patient’s physician, thus providing meticulous screening for subtle changes in AMD activity.11 This self-operated technology reduces the need for frequent in-person OCT examinations, providing a large advantage to retinal care during the pandemic. The utilization of self-monitoring technology combined with artificial intelligence has revolutionized eye care and will likely be a standard in optimal retinal care in the post–COVID-19 era (Fig. 3). Longitudinal studies focused on the follow-up rates following the implementation of self-monitoring technology in retina will help further characterize the impact of these advances.
Retina, Artificial Intelligence, and IoT
As noted with Notal Vision Home OCT, artificial intelligence is being integrated with at-home monitoring technology for identifying and mapping intraretinal and subretinal fluid.15 In the aforementioned study with a novel teleophthalmology triage system, the authors concluded that the integration of artificial intelligence may be the longstanding solution to managing eye emergencies amidst further waves of infection during the pandemic.6 Artificial intelligence has been rapidly adopted in the field of retina; this is evidenced by the diabetic retinopathy diagnostic system IDx-DR, the first AI diagnostic system approved by the US Food and Drug Administration.16 This landmark event for in 2018 broadened the potential for artificial intelligence to be utilized in health care. Within artificial intelligence, machine learning models often require large amounts of data for proper algorithm training.17 While diverse in function, the broad principle of machine learning can often be described as constructing and establishing algorithms that can be then applied to novel scenarios to autonomously provide successful outputs based on the framework and purpose of the algorithm.17 The large utilization of imaging in the field of ophthalmology allows for strong algorithm training for various machine learning classes due to sizable datasets. These machine learning techniques have high clinical relevance in ophthalmology including image enhancement,18 automated detection,16 and artifact identification19 which may contribute to more effective screening and/or earlier intervention of ophthalmic diseases. The revolutionary advent of machine learning in ophthalmology demonstrates how this technology will continue toward optimizing clinical care. However, several pertinent considerations have arisen with this powerful technology that must be addressed. As machine learning frameworks are built upon datasets, the representation of datasets must be taken into close consideration.20 Under-representation of diseases and people groups may worsen pre-existing health care disparities, thus highlighting the importance of diversity in machine learning. Zou and Schiebinger20 propose various short-term and long-term approaches to reduce bias in machine learning with the goal of optimizing this powerful technology to be inclusive and representative.
The increased adoption of virtual imaging clinic with electronically documented imaging grading outcomes will enable and accelerate the development of artificial intelligence–based algorithms in retina.10 In the near future, this technology will likely create a digital ecosystem with the IoT network.21 IoT refers to a broad network of devices that are interconnected and exchange data through the internet. Recent health care innovations in IoT have focused on low-cost sensors and wearable technology; this large amount of data provided by IoT can also be utilized for training machine learning models.22 During COVID-19, IoT was utilized for multiple innovative solutions including early diagnosis and monitoring of infected patients.23,24 By 2030, connected IoT devices are predicted to reach around 500 billion21 With the early adoption of artificial intelligence in health care, the field of retina will likely utilize IoT technology to further integrate this digital ecosystem to provide highly monitored health care delivery of retinal diseases.
Future of Retinal Telehealth and Security
From triaging of acute retinal emergencies to monitoring of stable retinal diseases, digital health care in retina has shown itself to be highly effective and likely to grow in the coming years. Future developments also include the potential for detecting early disease progression such as detecting myopia progression in children to adulthood25 or early detection of eyes at risk of complications such as pathologic myopia.26 However, improvements in imaging and imaging analysis while developing a large, robust image databank for algorithm development and validation is required to achieve implementation into clinical practice.27 Another consideration for increasing digital technology in the standard of care is the security and privacy of personal health information. In technologies such as artificial intelligence and IoT, the transmission and utilization of personal data from multiple devices leads to the need for increased cybersecurity measures. One of the limitations to the overall adoption of IoT is the consideration for security when utilizing multiple devices for personal information from personal devices.28 This security aspect of transmitting personal information may also be seen in various other technologies/techniques that utilize at-home devices such as at-home imaging and assessments. However, these digital advances are likely to increase care in the future, thus the implementation of trustworthy cybersecurity measures are essential. Blockchain technology has been highlighted as the leading technology to provide trusted cybersecurity for the digital ecosystem in health care.21,29 Blockchain is a revolutionary technology that utilizes peer-to-peer networking among a network of computers and has been highlighted to address the security concerns of IoT.28 While the technology is under development for full adoption in the field of retina and health care as a whole, Tan et al29 reported a proof-of-concept blockchain platform that was constructed for secure data transfer for a study detecting myopic macular degeneration and high myopia with retinal images. With technology advancements seen in the COVID-19 era, blockchain technology is likely to be involved in the future of trusted cybersecurity with expanding digital health care delivery.
COVID-19 presented a multitude of challenges in the field of retina that were met with innovative digital advancements. The lessons learned from the pandemic will likely impact how retina health care delivery is practiced in the post–COVID-19 era. From strategic telescreening techniques of retinal emergencies to diverse at-home monitoring systems, the future of retina will continue to build upon these advancements. In addition, future technology including IoT and blockchain cybersecurity will likely be instrumental in the coming era of retina care. While the pandemic severely disrupted retinal health deliver to society, there is hope that the challenges that were addressed will optimally preserve eyesight for the future.
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