Self-examination low-cost full-field OCT (SELFF-OCT) for patients with various macular diseases

[Digital remote monitoring of chronic retinal conditions-A clinical future tool? : Remote monitoring of chronic retinal conditions]

BACKGROUND

In view of the predicted increase in incidence and prevalence of chronic retinal diseases and undersupply of care in the population, telemedicine could contribute to reducing access barriers to healthcare and improving the results of treatment.

OBJECTIVE

A literature review on remote monitoring of chronic retinal diseases was carried out.

MATERIAL AND METHODS

The medical literature was searched for publications on remote monitoring of chronic retinal diseases. The results were compiled in a narrative overview.

RESULTS

The four main topics in the literature are: validation studies, implementation strategies, acceptance/target group analyses and health economic analyses. Remote monitoring systems are based on visual function tests, imaging or patient reports and have been particularly investigated in age-related macular degeneration (AMD) and diabetic eye disease (DED). Studies indicate positive effects regarding an optimization of clinical care and a favorable safety profile but randomized controlled trials are lacking for the majority of monitoring tools.

CONCLUSION

Remote monitoring could complement existing care structures for patients with chronic retinal diseases, especially AMD and DED. Promising systems are based on hyperacuity or optical coherence tomography, while patient-reported data are not commonly used; however, there is currently insufficient evidence justifying the use of remote monitoring systems in chronic retinal diseases in Europe and more research on the validation of remote monitoring systems is needed.

From real world data to real world evidence to improve outcomes in neuro-ophthalmology

Real-world data (RWD) can be defined as all data generated during routine clinical care. This includes electronic health records, disease-specific registries, imaging databanks, and data linkage to administrative databases. In the field of neuro-ophthalmology, the intersection of RWD and clinical practice offers unprecedented opportunities to understand and treat rare diseases. However, translating RWD into real-world evidence (RWE) poses several challenges, including data quality, legal and ethical considerations, and sustainability of data sources. This review explores existing RWD sources in neuro-ophthalmology, such as patient registries and electronic health records, and discusses the challenges of data collection and standardisation. We focus on research questions that need to be answered in neuro-ophthalmology and provide an update on RWE generated from various RWD sources. We review and propose solutions to some of the key barriers that can limit translation of a collection of data into impactful clinical evidence. Careful data selection, management, analysis, and interpretation are critical to generate meaningful conclusions.

Exploring single-mode VCSEL wavelength tuning for low-cost 3D optical coherence tomography and OCT angiography

Low-cost optical coherence tomography has recently emerged as a growing field due to the increased need for general availability of OCT devices outside of the clinics. One of the main obstacles in creating low-cost SS-OCT systems is the price of the laser. In this work, we study the influence of different tuning parameters (e.g., frequency, duty cycle, modulation curve, temperature) on the resulting bandwidth of the previously proposed low-cost single-mode thermally-tunable vertical-cavity surface-emitting laser (VCSEL) source at 850 nm. With optimal parameters, the laser achieves a tuning bandwidth of 10.2 nm at a 50 kHz A-scan rate. In addition, we show the first 3D rendered volume scans of both anterior and posterior segment using a custom VCSEL-based low-cost OCT setup. With the help of deep-learning-based denoising, it was possible to critically reduce the noise in single scans. Moreover, by investigating the phase stability, it became apparent that phase stability between sweeps increases with rising modulation frequencies, making the auxiliary interferometer obsolete. Thus, the system's 50 kHz tuning regimen is also suitable for functional extensions such as OCT angiography.

Evaluation of a self-imaging OCT for remote diagnosis and monitoring of retinal diseases

OBJECTIVES

To evaluate the feasibility and accuracy of a portable, self-imaging optical coherence tomography (OCT) for measuring central subfield thickness (CST) and achieving diagnostic concordance for retinal lesions compared with clinic-based spectral-domain OCT (SD-OCT).

METHODS

This comparative, cross-sectional study was conducted between August 2020 and February 2021. Two groups of adult participants were recruited: (1) a selected cohort of 160 participants with confirmed diagnosis and (2) a consecutive cohort of 315 participants recruited randomly. All participants underwent self-imaging OCT examination, as well as standard OCT examination. CST was automatically calculated for comparisons between the two OCT devices. Diagnostic concordance for retinal lesions and the success rate of self-imaging were assessed within the consecutive cohort.

RESULTS

In the selected cohort, self-imaging OCT images yielded consistent CST with SD-OCT, with a mean difference of 0.1±7.7 µm for normal eyes, 4.9±10.6 µm for macular oedema, -1.3±9.5 µm for choroidal neovascularisation, 5.0±7.8 µm for epiretinal membrane. The self-imaging OCT also demonstrated good repeatability, with a mean test-retest difference in CST of 0.7±3.9 µm and limits of agreement ranging from -6.9 to 8.3 µm. Additionally, within the consecutive cohort, interdevice κ values ranged for detecting various retinal lesions ranged from 0.8 to 1.0, except in the cases of retinal detachment (κ=0.5). All eyes (100%) in the selected cohort and 242 eyes (76.8%) in the consecutive cohort successfully completed self-imaging. Participants spent less time on self-imaging compared with SD-OCT operated by a technician (66.7±20.1 vs 73.3±32.5, p<0.01). A majority of participants (90%) found the self-imaging process 'easy' and 'comfortable'.

CONCLUSIONS AND RELEVANCE

This study demonstrates that our self-imaging OCT and clinical-used SD-OCT are highly consistent not only in measuring the CST but also in identifying most retinal lesions.

Home Optical Coherence Tomography Monitoring for Neovascular Age-Related Macular Degeneration: Transformative Technology or Cool Toy?

The pending introduction of home-based optical coherence tomography (OCT) in managing neovascular age-related macular degeneration (nAMD) has sparked interesting debates. Advocates assert that home-based OCT will revolutionize care of patients with nAMD, while skeptics question its real-world viability and point out its potential drawbacks. This article delves into the dichotomy, presenting the "pro" argument highlighting the transformative potential of home OCT and the "con" perspective, which scrutinizes the limitations and challenges to adapting the technology to the real-world setting. By exploring both sides of the discourse, we aim to address the promises and complexities surrounding the role of home OCT in the management of nAMD.

Optical coherence tomography in the management of diabetic macular oedema

Diabetic macular oedema (DMO) is the major cause of visual impairment in people with diabetes. Optical coherence tomography (OCT) is now the most widely used modality to assess presence and severity of DMO. DMO is currently broadly classified based on the involvement to the central 1 mm of the macula into non-centre or centre involved DMO (CI-DMO) and DMO can occur with or without visual acuity (VA) loss. This classification forms the basis of management strategies of DMO. Despite years of research on quantitative and qualitative DMO related features assessed by OCT, these do not fully inform physicians of the prognosis and severity of DMO relative to visual function. Having said that, recent research on novel OCT biomarkers development and re-defined classification of DMO show better correlation with visual function and treatment response. This review summarises the current evidence of the association of OCT biomarkers in DMO management and its potential clinical importance in predicting VA and anatomical treatment response. The review also discusses some future directions in this field, such as the use of artificial intelligence to quantify and monitor OCT biomarkers and retinal fluid and identify phenotypes of DMO, and the need for standardisation and classification of OCT biomarkers to use in future clinical trials and clinical practice settings as prognostic markers and secondary treatment outcome measures in the management of DMO.

Teleophthalmology and retina: a review of current tools, pathways and services

Telemedicine, the use of telecommunication and information technology to deliver healthcare remotely, has evolved beyond recognition since its inception in the 1970s. Advances in telecommunication infrastructure, the advent of the Internet, exponential growth in computing power and associated computer-aided diagnosis, and medical imaging developments have created an environment where telemedicine is more accessible and capable than ever before, particularly in the field of ophthalmology. Ever-increasing global demand for ophthalmic services due to population growth and ageing together with insufficient supply of ophthalmologists requires new models of healthcare provision integrating telemedicine to meet present day challenges, with the recent COVID-19 pandemic providing the catalyst for the widespread adoption and acceptance of teleophthalmology. In this review we discuss the history, present and future application of telemedicine within the field of ophthalmology, and specifically retinal disease. We consider the strengths and limitations of teleophthalmology, its role in screening, community and hospital management of retinal disease, patient and clinician attitudes, and barriers to its adoption.

Artificial intelligence for home monitoring devices

PURPOSE OF REVIEW

Home monitoring in ophthalmology is appropriate for disease stages requiring frequent monitoring or rapid intervention, for example, neovascular age-related macular degeneration (AMD) and glaucoma, where the balance between frequent hospital attendance versus risk of late detection is a constant challenge. Artificial intelligence approaches are well suited to address some challenges of home monitoring.

RECENT FINDINGS

Ophthalmic data collected at home have included functional (e.g. perimetry), biometric (e.g. intraocular pressure), and imaging [e.g. optical coherence tomography (OCT)] data. Potential advantages include early detection/intervention, convenience, cost, and visual outcomes. Artificial intelligence can assist with home monitoring workflows by handling large data volumes from frequent testing, compensating for test quality, and extracting useful metrics from complex data. Important use cases include machine learning applied to hyperacuity self-testing for detecting neovascular AMD and deep learning applied to OCT data for quantifying retinal fluid.

SUMMARY

Home monitoring of health conditions is useful for chronic diseases requiring rapid intervention or frequent data sampling to decrease risk of irreversible vision loss. Artificial intelligence may facilitate accurate, frequent, large-scale home monitoring, if algorithms are integrated safely into workflows. Clinical trials and economic evaluations are important to demonstrate the value of artificial intelligence-based home monitoring, towards improved visual outcomes.

Safety and efficacy of an artificial intelligence-enabled decision tool for treatment decisions in neovascular age-related macular degeneration and an exploration of clinical pathway integration and implementation: protocol for a multi-methods validation study

INTRODUCTION

Neovascular age-related macular degeneration (nAMD) management is one of the largest single-disease contributors to hospital outpatient appointments. Partial automation of nAMD treatment decisions could reduce demands on clinician time. Established artificial intelligence (AI)-enabled retinal imaging analysis tools, could be applied to this use-case, but are not yet validated for it. A primary qualitative investigation of stakeholder perceptions of such an AI-enabled decision tool is also absent. This multi-methods study aims to establish the safety and efficacy of an AI-enabled decision tool for nAMD treatment decisions and understand where on the clinical pathway it could sit and what factors are likely to influence its implementation.

METHODS AND ANALYSIS

Single-centre retrospective imaging and clinical data will be collected from nAMD clinic visits at a National Health Service (NHS) teaching hospital ophthalmology service, including judgements of nAMD disease stability or activity made in real-world consultant-led-care. Dataset size will be set by a power calculation using the first 127 randomly sampled eligible clinic visits. An AI-enabled retinal segmentation tool and a rule-based decision tree will independently analyse imaging data to report nAMD stability or activity for each of these clinic visits. Independently, an external reading centre will receive both clinical and imaging data to generate an enhanced reference standard for each clinic visit. The non-inferiority of the relative negative predictive value of AI-enabled reports on disease activity relative to consultant-led-care judgements will then be tested. In parallel, approximately 40 semi-structured interviews will be conducted with key nAMD service stakeholders, including patients. Transcripts will be coded using a theoretical framework and thematic analysis will follow.

ETHICS AND DISSEMINATION

NHS Research Ethics Committee and UK Health Research Authority approvals are in place (21/NW/0138). Informed consent is planned for interview participants only. Written and oral dissemination is planned to public, clinical, academic and commercial stakeholders.

Perspectives on the Home Monitoring of Macular Disease

Recent advancements in imaging technology have led to increasing interest in home monitoring of macular disease. The prevalence of macular disease is projected to rise considerably over time, leading to a significant burden on hospital services for age-related macular degeneration and diabetic macular edema. Home monitoring has the potential to augment conventional hospital assessment and so enable improved access to clinical care for low- and moderate-risk patients, while also allowing sensitive detection of early signs of disease that may require prompt intervention. Despite this, there are significant considerations before large-scale implementation could be possible. These are related to both the current availability of home monitoring technology and the logistical barriers to its widespread introduction. Access to home monitoring is also likely to be more challenging in lower-income communities and countries, with subsequent implications for health inequality that will need to be considered and addressed appropriately.

Analysis of the Long-term Visual Outcomes of ForeseeHome Remote Telemonitoring: The ALOFT Study

PURPOSE

To evaluate long-term visual acuity (VA) and performance of a monitoring strategy with a self-operated artificial-intelligence-enabled home monitoring system in conjunction with standard care for early detection of neovascular age-related macular degeneration (nAMD).

DESIGN

Retrospective review.

SUBJECTS

Patients with dry-age-related macular degeneration from 5 referral clinics.

METHODS

Clinical data of patients monitored with ForeseeHome (FSH) device from August 2010 to July 2020 were reviewed.

MAIN OUTCOME MEASURES

Visual acuity at baseline, VA at diagnosis of nAMD for eyes that converted while monitored, and VA from the final study follow-up, weekly frequency of use, duration of monitoring, modality of conversion diagnosis (system alert vs. detection by other standard care means), and duration and number of treatments since conversion to final study follow-up were collected.

RESULTS

We reviewed 3334 eyes of 2123 patients with a mean (standard deviation [SD]) age of 74(8) years, monitored for a mean (SD) duration of 3.1 (2.4) years, with a total of 1 706 433 tests in 10 474 eye-monitoring years. The mean (SD) weekly use per patient was 5.2 (3.4), and it was persistent over the usage period. Two hundred eighty-five eyes converted while monitored at an annual rate of 2.72% and were treated with a mean (SD) 17.3 (16.5) injections over a mean (SD) 2.7 (2.0) years, with 6.4 (3.1) injections per year for eyes treated for > 1 year. The median VAs at baseline and at final follow-up for eyes that did not convert were 20/27 and 20/34 with a median change of 0.0 letters. The median VAs at baseline, conversion, and final follow-up for eyes that converted during the monitoring period were 20/30, 20/39, and 20/32 with a median change from baseline to conversion, baseline to recent, and conversion to recent of -4, -4, and 0 letters, respectively. Fifty-two percent of conversions detected had a system alert before conversion. Forty-eight percent of patients were detected by symptoms or routine visit. Patients experienced a non-nAMD alert on average every 4.6 years. At conversion and at final follow-up, the proportion (95% CI) of eyes that maintained ≥ 20/40 was 84% (78% to 88%) and 82% (76% to 86%), respectively.

CONCLUSIONS

Patients in the FSH monitoring program showed excellent long-term VA years after conversion to nAMD.

The Development and Clinical Application of Innovative Optical Ophthalmic Imaging Techniques

The field of ophthalmic imaging has grown substantially over the last years. Massive improvements in image processing and computer hardware have allowed the emergence of multiple imaging techniques of the eye that can transform patient care. The purpose of this review is to describe the most recent advances in eye imaging and explain how new technologies and imaging methods can be utilized in a clinical setting. The introduction of optical coherence tomography (OCT) was a revolution in eye imaging and has since become the standard of care for a plethora of conditions. Its most recent iterations, OCT angiography, and visible light OCT, as well as imaging modalities, such as fluorescent lifetime imaging ophthalmoscopy, would allow a more thorough evaluation of patients and provide additional information on disease processes. Toward that goal, the application of adaptive optics (AO) and full-field scanning to a variety of eye imaging techniques has further allowed the histologic study of single cells in the retina and anterior segment. Toward the goal of remote eye care and more accessible eye imaging, methods such as handheld OCT devices and imaging through smartphones, have emerged. Finally, incorporating artificial intelligence (AI) in eye images has the potential to become a new milestone for eye imaging while also contributing in social aspects of eye care.

Self-Examination Low-Cost Full-Field Optical Coherence Tomography (SELFF-OCT) for neovascular age-related macular degeneration: a cross-sectional diagnostic accuracy study

OBJECTIVES

Self-Examination Low-Cost Full-Field Optical Coherence Tomography (SELFF-OCT) is a novel OCT technology that was specifically designed for home monitoring of neovascular age-related macular degeneration (AMD). First clinical findings have been reported before. This trial investigates an improved prototype for patients with AMD and focusses on device operability and diagnostic accuracy compared with established spectral-domain OCT (SD-OCT).

DESIGN

Prospective single-arm diagnostic accuracy study.

SETTING

Tertiary care centre (University Eye Clinic).

PARTICIPANTS

46 patients with age-related macular degeneration.

INTERVENTIONS

Patients received short training in device handling and then performed multiple self-scans with the SELFF-OCT according to a predefined protocol. Additionally, all eyes were examined with standard SD-OCT, performed by medical personnel. All images were graded by at least 2 masked investigators in a reading centre.

PRIMARY OUTCOME MEASURE

Rate of successful self-measurements.

SECONDARY OUTCOME MEASURES

Sensitivity and specificity of SELFF-OCT versus SD-OCT for different biomarkers and necessity for antivascular endothelial growth factor (anti-VEGF) treatment.

RESULTS

In 86% of all examined eyes, OCT self-acquisition resulted in interpretable retinal OCT volume scans. In these patients, the sensitivity for detection of anti-VEGF treatment necessity was 0.94 (95% CI 0.79 to 0.99) and specificity 0.95 (95% CI 0.82 to 0.99).

CONCLUSIONS

SELFF-OCT was used successfully for retinal self-examination in most patients, and it could become a valuable tool for retinal home monitoring in the future. Improvements are in progress to reduce device size and to improve handling, image quality and success rates.

TRIAL REGISTRATION NUMBER

DRKS00013755, CIV-17-12-022384.

Evaluation of a self-imaging SD-OCT system designed for remote home monitoring

PURPOSE

To compare identification rates of retinal fluid of the Notal Vision Home Optical Coherence Tomography (OCT) device (NVHO) when used by people with age-related macular degeneration (AMD) to those captured by a commercial OCT.

METHODS

Prospective, cross-sectional study where patients underwent commercial OCT imaging followed by self-imaging with either the NVHO 2.5 or the NVHO 3 in clinic setting. Outcomes included patients' ability to acquire analyzable OCT images with the NVHO and to compare those with commercial images.

RESULTS

Successful images were acquired with the NVHO 2.5 in 469/531 eyes (88%) in 264/290 subjects (91%) with the mean (SD) age of 78.8 (8.8); 153 (58%) were female with median visual acuity (VA) of 20/40. In the NVHO 3 cohort, 69 eyes of 45 subjects (93%) completed the self-imaging. Higher rates of successful imaging were found in eyes with VA ≥ 20/320. Positive percent agreement/negative percent agreement for detecting the presence of subretinal and/or intraretinal fluid when reviewing for fluid in three repeated volume scans were 97%/95%, respectively for the NVHO v3.

CONCLUSION

Self-testing with the NVHO can produce high quality images suitable for fluid identification by human graders, suggesting the device may be able to complement standard-of-care clinical assessments and treatments.

Telemedicine for the Diagnosis and Management of Age-Related Macular Degeneration: A Review

Use of ophthalmic telemedicine for patients with age-related macular degeneration (AMD) has shown remarkable advances over recent years. The recent COVID pandemic accelerated this transition since in-person evaluation of elderly patients at high risk for advanced AMD and severe vision loss were also at higher risk for complications from COVID infection. To date, ophthalmic telemedicine has been successfully used in remote retinal consultation by general ophthalmologists for AMD management, hybrid testing visits with both in-office testing and remote evaluation, as well as early successes in home-based remote monitoring of patients with high-risk AMD. We therefore review the current literature and evidence base related to ophthalmic telemedicine for AMD.

Microscopic optical coherence tomography (mOCT) at 600 kHz for 4D volumetric imaging and dynamic contrast

Volumetric imaging of dynamic processes with microscopic resolution holds a huge potential in biomedical research and clinical diagnosis. Using supercontinuum light sources and high numerical aperture (NA) objectives, optical coherence tomography (OCT) achieves microscopic resolution and is well suited for imaging cellular and subcellular structures of biological tissues. Currently, the imaging speed of microscopic OCT (mOCT) is limited by the line-scan rate of the spectrometer camera and ranges from 30 to 250 kHz. This is not fast enough for volumetric imaging of dynamic processes in vivo and limits endoscopic application. Using a novel CMOS camera, we demonstrate fast 3-dimensional OCT imaging with 600,000 A-scans/s at 1.8 µm axial and 1.1 µm lateral resolution. The improved speed is used for imaging of ciliary motion and particle transport in ex vivo mouse trachea. Furthermore, we demonstrate dynamic contrast OCT by evaluating the recorded volumes rather than en face planes or B-scans. High-speed volumetric mOCT will enable the correction of global tissue motion and is a prerequisite for applying dynamic contrast mOCT in vivo. With further increase in imaging speed and integration in flexible endoscopes, volumetric mOCT may be used to complement or partly replace biopsies.

Prospective, Longitudinal Pilot Study

Purpose

Design

Participants

Methods

Main Outcome Measures

Results

Conclusions