Comparison of Peristat Online Perimetry with the Humphrey Perimetry in a Clinic-Based Setting

Comparing a Head-Mounted Smartphone Visual Field Analyzer to Standard Automated Perimetry in Glaucoma: A Prospective Study

PRCIS

Wang et al compare an FDA-registered head-mounted smartphone device (PalmScan VF2000) with standard automated perimetry (SAP) in glaucoma patients and find that the head-mounted device may not fully recapitulate SAP testing.

PURPOSE

This study prospectively compared visual field testing using the PalmScan VF2000 Visual Field Analyzer, a head-mounted smartphone device, with standard automated perimetry (SAP).

METHODS

Patients with glaucoma undergoing Humphrey Field Analyzer SAP testing were asked to complete in-office PalmScan testing using a Samsung S5 smartphone in a virtual reality-style headset. Glaucoma severity was defined as SAP mean deviation (MD) >-6 dB for mild, between -6 and -12 dB for moderate, and <-12 dB for severe. Global parameters MD and pattern SD from PalmScan and SAP were compared using t -tests and Bland-Altman analyses. Bland-Altmann analyses of PalmScan and SAP MD were conducted for the superonasal, superotemporal, inferonasal, and inferotemporal visual field quadrants. The repeatability of PalmScan was assessed using Spearman's correlations and intraclass correlation coefficients (ICCs).

RESULTS

Fifty-one patients (51 eyes) completed both SAP and PalmScan testing and met the criteria for analysis. Compared with SAP, global MD and pattern SD measurements from PalmScan differed by an average of +0.62±0.26 dB (range: -3.25 to +4.60 dB) and -1.00±0.24 dB (range: -6.03 to +2.77 dB), respectively, while MD scores from individual visual field quadrants differed by as much as -6.58 to +11.43 dB. The agreement between PalmScan and SAP in classifying glaucoma severity was 86.3% across all eyes. PalmScan and SAP identified the same quadrant as having the worst visual field defect in 66.7% of eyes.

CONCLUSIONS

Despite advantages in cost and accessibility, the PalmScan head-mounted perimetry device may not be able to fully recapitulate SAP testing.

Novel Technologies in Artificial Intelligence and Telemedicine for Glaucoma Screening

PURPOSE

To provide an overview of novel technologies in telemedicine and artificial intelligence (AI) approaches for cost-effective glaucoma screening.

METHODS/RESULTS

A narrative review was performed by summarizing research results, recent developments in glaucoma detection and care, and considerations related to telemedicine and AI in glaucoma screening. Telemedicine and AI approaches provide the opportunity for novel glaucoma screening programs in primary care, optometry, portable, and home-based settings. These approaches offer several advantages for glaucoma screening, including increasing access to care, lowering costs, identifying patients in need of urgent treatment, and enabling timely diagnosis and early intervention. However, challenges remain in implementing these systems, including integration into existing clinical workflows, ensuring equity for patients, and meeting ethical and regulatory requirements. Leveraging recent work towards standardized data acquisition as well as tools and techniques developed for automated diabetic retinopathy screening programs may provide a model for a cost-effective approach to glaucoma screening.

CONCLUSION

Leveraging novel technologies and advances in telemedicine and AI-based approaches to glaucoma detection show promise for improving our ability to detect moderate and advanced glaucoma in primary care settings and target higher individuals at high risk for having the disease.

Repeatability of Online Circular Contrast Perimetry Compared to Standard Automated Perimetry

PRCIS

Online circular contrast perimetry provides visual field assessment on any computer or tablet with no extra hardware. It has good test repeatability and reliability that is comparable with standard automated perimetry. It holds promise for use in disease screening and surveillance to expand the provision of glaucoma care.

PURPOSE

To evaluate the repeatability of online circular contrast perimetry (OCCP) compared to standard automated perimetry (SAP) in normal participants and patients with stable glaucoma over 18 weeks.

METHODS

Thirty-six participants (13 normal controls and 23 patients with open angle glaucoma) were recruited. OCCP and SAP perimetry tests were performed twice at baseline, then at 6, 12, and 18 weeks. Global perimetric indices were compared between perimetry types and analyzed for short-term and intermediate-term repeatability.

RESULTS

There were no statistically significant changes over time for both OCCP and SAP across all groups for mean deviation (MD), pattern standard deviation, and visual index/visual field index ( P >0.05). Test-retest intraclass correlation coefficients (ICCs) for OCCP MD were excellent at baseline (0.98, 95% CI: 0.89-0.99) and good at 18 weeks (0.88, 95% CI: 0.51-0.98). SAP test-retest ICCs were excellent at baseline (0.94, 95% CI: 0.70-0.99) and 18 weeks (0.97, 95% CI: 0.84-0.99). Inter-test ICCs were good, ranging from 0.84 to 0.87. OCCP testing time was shorter than SAP (5:29 ± 1:24 vs. 6:00 ± 1:05, P <0.001). OCCP had similar false-positive (3.84 ± 3.32 vs. 3.66 ± 4.53, P =0.48) but lower false-negative (0.73 ± 1.52 vs. 4.48 ± 5.00, P <0.001) and fixation loss responses (0.91 ± 1.32 vs. 2.02 ± 2.17, P <0.001).

CONCLUSIONS

OCCP allows visual field assessment on any computer screen with no additional hardware. It demonstrated good repeatability and reliability with similar performance indices to SAP in both the short term and intermediate term. OCCP has the potential to be utilized as a glaucoma screening and surveillance tool for in-clinic and at-home testing, expanding the provision of care.

Development and Validation of an Internet-Based Remote Perimeter (Perimouse)

Purpose

We sought to validate the feasibility of Perimouse, an internet-based remote perimeter that allows for natural fixation and can be performed on most computers via a web page.

Methods

In this cross-sectional study, Perimouse evaluated the visual field of 45 healthy people and 27 patients with primary open-angle glaucoma on a laptop. Participants used a mouse cursor to locate new dots on the screen that were determined by preset saccade vectors. A "click and confirm" strategy was used to eliminate the unwanted visual search. Dot brightness was either fixed at 12 dB in the suprathreshold program (screening program) or variable in the threshold program. We compared Perimouse outcomes with the Humphrey Field Analyzer (HFA) 24-2 Swedish Interactive Testing Algorithm standard program.

Results

In the screening program, Perimouse showed moderate to high concordance with HFA. The intraclass coefficient ranged from 0.58 to 0.86 in different areas of Garway-Heath mapping. In the threshold program, normal subjects had threshold ranging from 19 to 16 dB, presenting sensitivity changes according to the "hill of vision". The test-retest difference was 0.09 dB. Habitual spectacle correction and environmental luminance (2-337 lux) had little impact on the central or peripheral threshold (P > 0.05). The correlation between Perimouse and HFA threshold sensitivity was strong (R = 0.950), although Perimouse mean defect was 4.40 dB higher than the HFA mean defect.

Conclusions

Perimouse is a reliable visual field test that correlates strongly with HFA. It shows potential for population screening and monitoring visual field defects.

Translational Relevance

Perimouse assesses the visual field using saccade vectors without eye trackers, enhancing its accessibility via a web page.

Recent developments of telemedicine in glaucoma

PURPOSE OF REVIEW

Telemedicine has an increasingly significant role in the fields of ophthalmology and glaucoma. This review covers recent advancements in the development and optimization of teleglaucoma techniques and applications.

RECENT FINDINGS

Glaucoma monitoring and diagnosis via remote tonometry, perimetry, and fundus imaging have become a possibility based on recent developments. Many applications work in combination with smart devices, virtual reality, and artificial intelligence and have been tested in patient populations against conventional "reference-standard" measurement tools, demonstrating promising results. Of note, there is still much progress to be made in teleglaucoma and telemedicine at large, such as accessibility to internet, broadband, and smart devices, application affordability, and reimbursement for remote services. However, continued development and optimization of these applications suggest that the implementation of remote monitoring will be a mainstay for glaucoma patient care.

SUMMARY

Especially since the beginning of the COVID-19 pandemic, remote patient care has taken on an important role in medicine and ophthalmology. Remote versions of tonometry, perimetry, and fundus imaging may allow for a more patient-centered and accessible future for glaucoma care.

Online Circular Contrast Perimetry via a Web-Application: Establishing a Normative Database for Central 10-Degree Perimetry

Purpose

To establish a normative database using a central 10-degree grid pattern for the online circular contrast perimetry (OCCP) application.

Participants

Fifty participants with mean age 65 ± 13 years were selected for this study. One eye from each participant that met inclusion criteria was randomly included in the cohort.

Methods

The web-application delivered online 52-loci perimetry in a central 10-degree pattern using circular flickering targets. These targets consist of concentric sinusoidal alternating contrast rings. Users were guided by the application to the correct viewing distance and head position using in-built blind spot localization and webcam monitoring. A spinning golden star was used as the fixation target and patients performed the test in a darkened room following standard automated perimetry (SAP).

Results

The reliability rates and global indices for OCCP were similar to SAP. OCCP mean sensitivity reduced with age at a similar rate to SAP. Mean sensitivity per loci of 10-degree OCCP was greater than SAP by 1.24 log units (95% CI 1.23 to 1.26) and obeyed a physiological hill of vision. Small differences existed in mean sensitivities between OCCP and SAP which increased with increasing spot eccentricity. Mean deviation (MD) displayed good agreement between the two tests.

Conclusion

Central 10-degree online circular contrast perimetry via a computer-based application has comparable perimetric results to standard automated perimetry in a normal cohort.

Online Circular Contrast Perimetry: A Comparison to Standard Automated Perimetry

PURPOSE

The aim was to validate and compare the diagnostic accuracy of a novel 24-degree, 52-loci online circular contrast perimetry (OCCP) application to standard automated perimetry (SAP).

DESIGN

Prospective cohort study.

METHODS

Two hundred and twenty participants (125 normal controls, 95 open angle glaucoma patients) were included. Agreement, correlation, sensitivity, specificity, and area under receiver operating curves (AUC) were compared for parameters of OCCP, SAP, and optical coherence tomography (OCT) for the retinal nerve fiber layer and macular ganglion cell complex inner plexiform layer.

RESULTS

Pointwise sensitivity for OCCP was greater than SAP by 1.02 log units (95% CI: 0.95-1.08); 95% limits of agreement 0.860 to 1.17. Correlation and agreement for global indices and regional zones between OCCP and SAP were strong. OCCP mean deviation (MD) AUC was 0.885±0.08, similar to other instruments' parameters with the highest AUC: SAP MD (0.851±0.08), OCT retinal nerve fiber layer inferior thickness (0.908±0.07), OCT ganglion cell complex inner plexiform layer inferior thickness (0.849±0.08), P>0.05. At best cutoff, OCCP MD sensitivity/specificity were comparable to SAP MD (90/74 vs 94/65%).

CONCLUSIONS

OCCP demonstrates similar perimetric sensitivities to SAP and similar AUC to SAP and OCT in distinguishing glaucoma patients from controls. OCCP holds promise as a glaucoma surveillance and screening tool, with the potential to be utilized for in-clinic and at-home perimetry and expand community testing.

Personal Computer-Based Visual Field Testing as an Alternative to Standard Automated Perimetry

Introduction Standard automated perimetry (SAP) is the gold standard of visual field assessment in patients with neuro-ophthalmic conditions. Glaucoma is a progressive optic neuropathy characterized by damage to the ganglion cell complex with corresponding visual field defects and intraocular pressure (IOP) being the only modifiable ocular risk factor. Recent advances in technology have paved the way for remote screening and monitoring of visual field defects with the aid of a computer or tablet-based software. One such personal computer (PC)-based software is 'Specvis', which has shown promising reliability as compared to SAP. The primary objective of this study was to compare Specvis and Humphrey Field Analyzer (HFA) visual field reports in the graphical domain while secondary objectives were to estimate the ease of use of Specvis in comparison to HFA and comparison of test duration between Specvis and HFA.  Materials and methods This was a cross-sectional validation study performed at a tertiary care ophthalmology institute in Rawalpindi, Pakistan. Subjects presenting to the outpatient department were recruited based on consecutive sampling technique and were divided into healthy and diseased groups. Basic data collection instrument after informed consent was filled with demographic data, ophthalmic data, disease condition, and attached with analysis reports of both HFA and Specvis for assessment by three senior ophthalmology consultants independently. A total of 218 eyes of 109 subjects were included in this pilot study. SAP was done on the VF 30-2 program using HFA 3. The same patient then performed the visual field assessment on a PC with Specvis installed and settings adjusted to match the VF 30-2 program of HFA as closely as possible. Visual fields of a subject obtained from HFA and Specvis were then coupled and sent to three different senior ophthalmologists. The assessment was done by comparing the greyscale visual field printouts in the graphical domain and scored based on a 5-point Likert scale which were then analyzed for inter-observer reliability. After each test, all subjects were asked to rate the difficulty level of performing the test on HFA and Specvis based on a 5-point Likert scale. The duration of the test performed on HFA and Specvis was also noted for comparison. Results We observed male preponderance in our study participants (n=128, 58.72%). The majority of the participants were non-diseased (n=170, 77.98%) while advanced glaucoma was the commonest disease in the diseased group (n = 22, 10.09%). The mean age of the participants was 40.71 (SD=15.24). The observations for the HFA test duration had an average of 213.33 seconds (SD=33.49, Min=174.00, Max=314.00) while the Specvis test duration had an average of 267.36 seconds (SD=35.98, Min=228.00, Max=370.00). A significant positive correlation was observed between score 1, score 2, and score 3 given by the three ophthalmologists. A significant negative correlation was observed between ease of using HFA and age, with a correlation of -.28. A significant negative correlation was also observed between ease of using Specvis and age. Conclusion Specvis, a computer-based free open-source software used in our study, can give promising results in diagnosing as well as monitoring the progression of visual field defects. It can act as a significantly cost-effective and readily available bridge between visual field examination by confrontation method and SAP.

Circular Contrast Perimetry via Web Application: A Patient Appraisal and Comparison to Standard Automated Perimetry

Purpose

The purpose of the study was to compare a novel, 24°, 52-locus online circular contrast perimetry (OCCP) application against standard automated perimetry (SAP) in terms of both diagnostic accuracy and patient attitudes.

Design

This was a cross-sectional study.

Subjects

Ninety-five participants (42 controls and 53 open-angle glaucoma patients) were included.

Methods

Participants performed both perimetry tests and then completed an online survey. Subjective feedback responses were collected.

Main Outcome Measures

Agreement, sensitivity, specificity, and area under receiver operating curves (AUCs) were compared for the parameters of OCCP, SAP, and OCT for the retinal nerve fiber layer (RNFL) and macular ganglion cell complex inner plexiform layer (GCC + IPL). Participant attitudes toward the OCCP test versus the SAP test, in both glaucoma patients and controls, were compared. Rasch analysis assessed the psychometric properties of the survey and intergroup variability.

Results

The AUC for OCCP mean deviation (MD) was 0.959 ± 0.02. Compared with other instruments' parameters with the highest AUC, it was superior to SAP MD (0.871 ± 0.04, P = 0.03) and OCT GCC + IPL (0.871 ± 0.04, P = 0.03) and similar to OCT RNFL inferior thickness (IT) (0.917 ± 0.03, no significance). Online circular contrast perimetry pointwise sensitivity was less than SAP by 4.30 dB (95% confidence interval = 4.02-4.59); 95% limits of agreement ranged from -6.28 to -2.33 dB. At the best cutoff, the OCCP MD had a sensitivity of 98% and specificity of 85% for detecting glaucoma. Cohen's kappa demonstrated good agreement with SAP MD (0.69) and OCT RNFL IT (0.62) and moderate agreement with OCT GCC + IPL IT (0.57). Participants preferred OCCP across most survey parameters (P < 0.0001). Rasch analysis demonstrated no differential item functioning for clinical group, gender, or age.

Conclusions

With similar diagnostic metrics to SAP, OCCP offers an improved user experience with the potential to increase the provision of care and improve disease surveillance outcomes.

Spotlight on iPad Visual Field Tests Efficacy

Tablet based perimetry has the potential to be used as a low-cost, portable method for glaucoma screening. With the advent of tablets with large dynamic luminance range and high spatial resolution, perimetry applications can test visual field locations within the central 30 degrees, just like bowl perimetry. Tablet perimetry has garnered interest in this COVID era as it can be promptly done in the waiting room or even from the comfort of home. The current review focuses on evaluating glaucoma detection sensitivities, diagnostic abilities and correlation of each parameter and examination time of the iPad based perimetry applications with those of HFA.

Home-Based Perimetry for Glaucoma: Where Are We Now?

PURPOSE

To systematically summarize the current literature on home-based perimeters for glaucoma.

METHODS

A systematic review was conducted in accordance with the PRISMA-DTA checklist. Studies reporting portable perimeters designed for home use were retrieved from electronic databases and handsearching of reference lists of relevant publications. Studies reporting diagnostic accuracy data were evaluated with the QUADAS-2 tool and using standard automated perimetry as the reference standard. Other aspects of the technology such as detection of disease progression and patient acceptability were also included. Data were reported in a narrative and tabular format.

RESULTS

Of 18 included studies, 10 evaluated tablet-based perimeters, 4 evaluated web-based perimeters, and 4 evaluated head-mounted displays. Most studies used a clinic or laboratory setting. All studies reporting diagnostic accuracy data had high risk of bias in at least one domain. Across studies, sensitivity ranged from 54% in detecting mild to 91% in detecting moderate/severe glaucoma patients from controls, while specificity was between 50% and 100% for any form of glaucoma. The reported acceptability was high but had high risk of bias.

CONCLUSION

Several promising technologies designed for home-based perimetry have been reported. Current studies used a controlled setting in highly selected populations. There is uncertainty on the performance and value of home-based perimetry for glaucoma. Additional efforts are required to elucidate the ability of the home-based perimeters to detect glaucoma and disease progression in real life situations.

Online circular contrast perimetry via a web-application: optimising parameters and establishing a normative database

PURPOSE

To establish a normative database and optimise parameters for personal-computer based perimetry via a web-application using circular contrast targets.

METHODS

Online 24-degree 52-loci perimetry was delivered through a web-application using circular flickering contrast targets. Embedding contrast differentials within targets allows calculation of relative decibel (rdB) per 256-bit greyscale level differential. Target light-band maximum brightness colour was fixed, while the dark-band varied to achieve the desired rdB level. A staircase system was used with two reversals ranging from 0 to 36 rdB levels. Blind spot localisation at the start of the test was used to optimise viewing distance and subsequently count fixation losses. Gaze was maintained on a spinning golden star which moves mid-test to maximise sampling area. Patients performed the test to each eye separately using a computer in a darkened room at 40-45 cm.

RESULTS

158 eyes of 101 patients completed the Online Circular Contrast Perimetry (OCCP) test. Mean age was 62.9 ± 14.3 years old. Mean sensitivity reduced with age, at 1.0 relative decibel per decade. Mean sensitivity per locus correlated with standard automated perimetry (SAP) in a physiological hill of vision, with an average difference of 4.02 decibels (95% confidence interval (CI) = 3.77-4.27, p < 0.001) and good agreement between tests.

CONCLUSIONS

Online circular contract perimetry provides accurate perimetric testing with comparable results to standard automated perimetry.

Diagnostic Performance of the PalmScan VF2000 Virtual Reality Visual Field Analyzer for Identification and Classification of Glaucoma

Purpose

To evaluate the diagnostic test properties of the Palm Scan VF2000Ⓡ Virtual Reality Visual Field Analyzer for diagnosis and classification of the severity of glaucoma.

Methods

This study was a prospective cross-sectional analysis of 166 eyes from 97 participants. All of them were examined by the HumphreyⓇ Field Analyzer (used as the gold standard) and the Palm Scan VF 2000Ⓡ Virtual Reality Visual Field Analyzer on the same day by the same examiner. We estimated the kappa statistic (including 95% confidence interval [CI]) as a measure of agreement between these two methods. The diagnostic test properties were assessed using sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

Results

The sensitivity, specificity, PPV, and NPV for the Virtual Reality Visual Field Analyzer for the classification of individuals as glaucoma/non-glaucoma was 100%. The general agreement for the classification of glaucoma between these two instruments was 0.63 (95% CI: 0.56-0.78). The agreement for mild glaucoma was 0.76 (95% CI: 0.61-0.92), for moderate glaucoma was 0.37 (0.14-0.60), and for severe glaucoma was 0.70 (95% CI: 0.55-0.85). About 28% of moderate glaucoma cases were misclassified as mild and 17% were misclassified as severe by the virtual reality visual field analyzer. Furthermore, 20% of severe cases were misclassified as moderate by this instrument.

Conclusion

The instrument is 100% sensitive and specific in detection of glaucoma. However, among patients with glaucoma, there is a relatively high proportion of misclassification of severity of glaucoma. Thus, although useful for screening of glaucoma, it cannot replace the HumphreyⓇ Field Analyzer for the clinical management in its current form.

Screening for Glaucomatous Visual Field Defects in Rural Australia with an iPad

Aim and objective

Developing improved methods for early detection of visual field defects is pivotal to reducing glaucoma-related vision loss. The Melbourne Rapid Fields screening module (MRF-S) is an iPad-based test, which allows suprathreshold screening with zone-based analysis to rapidly assess the risk of manifest glaucoma. The versatility of MRF-S has potential utility in rural areas and during infectious pandemics. This study evaluates the utility of MRF-S for detecting field defects in non-metropolitan settings.

Materials and methods

This was a prospective, multicenter, cross-sectional validation study. Two hundred and fifty-two eyes of 142 participants were recruited from rural sites through two outreach eye services in Australia. Participants were tested using MRF-S and compared with a reference standard; either Zeiss Humphrey Field Analyzer or Haag-Streit Octopus performed at the same visit. Standardized questionnaires were used to assess user acceptability. Major outcome measures were the area under the curve (AUC) for detecting mild and moderate field defects defined by the reference tests, along with corresponding performance characteristics (sensitivity, specificity).

Results

The mean test duration for MRF-S was 1.88 minutes compared with 5.92 minutes for reference tests. The AUCs for mild and moderate field defects were 0.81 [95% confidence interval (CI): 0.75–0.87] and 0.87 (95% CI: 0.83–0.92), respectively, indicating very good diagnostic accuracy. Using a risk criterion of 55%, MRF-S identified moderate field defects with a sensitivity and specificity of 88.4 and 81.0%, respectively.

Conclusion and clinical significance

The MRF-S iPad module can identify patients with mild and moderate field defects while delivering favorable user acceptability and short test duration. This has potential application within rural locations and amidst infectious pandemics.

How to cite this article

Chia MA, Trang E, Agar A, et al. Screening for Glaucomatous Visual Field Defects in Rural Australia with an iPad. J Curr Glaucoma Pract 2021;15(3):125–131.

Telehealth and Screening Strategies in the Diagnosis and Management of Glaucoma

Telehealth has become a viable option for glaucoma screening and glaucoma monitoring due to advances in technology. The ability to measure intraocular pressure without an anesthetic and to take optic nerve photographs without pharmacologic pupillary dilation using portable equipment have allowed glaucoma screening programs to generate enough data for assessment. At home, patients can perform visual acuity testing, web-based visual field testing, rebound tonometry, and video visits with the physician to monitor for glaucomatous progression. Artificial intelligence will enhance the accuracy of data interpretation and inspire confidence in popularizing telehealth for glaucoma.

Glaucoma care during the coronavirus disease 2019 pandemic

PURPOSE OF REVIEW

The current article reviews the impact of the coronavirus disease 2019 (COVID-19) pandemic on the delivery of ophthalmic, and specifically, glaucoma care.

RECENT FINDINGS

Literature from the review period includes case series demonstrating the presence of severe acute respiratory syndrome coronavirus 2 RNA in the conjunctival secretions of patients with laboratory-confirmed COVID-19. The global ophthalmology community published reports outlining the enhanced infection control measures undertaken by different institutions around the world to mitigate transmission of the novel coronavirus. Telemedicine has been increasingly implemented in glaucoma practices to reduce in-office patient volume. New data regarding the efficacy and feasibility of tools for home monitoring of intraocular pressure, virtual visual field testing, and remote disc photography are reviewed.

SUMMARY

COVID-19 has posed a global public health threat due to the severity of its contagion and associated morbidity and mortality. Glaucoma specialists have responded to the pandemic with innovative modifications to reduce viral transmission and optimize patient and staff safety in the office and operating room. The role of teleglaucoma has expanded and will continue to evolve as remote diagnostic devices undergo further refinement and validation.

Virtual Ophthalmology: Telemedicine in a COVID-19 Era

Purpose

To discuss the effects of the severe acute respiratory syndrome coronavirus 2 betacoronavirus on ambulatory ophthalmology practices, the value proposition of telemedicine, teleophthalmology implementation methodologies, and the accelerated future of telemedicine.

Design

Review of the current telehealth landscape including usage, policies, and techniques for ambulatory practice integration.

Methods

We provide author-initiated review of recent trends in telehealth, governmental recommendations for health care delivery during the COVID-19 pandemic, and a PubMed Central query for telemedicine in ophthalmology or teleophthalmology. In addition, the authors' comprehensive experience in telemedicine design and implementation is provided.

Results

We provide a summary describing the present state of telehealth, teleophthalmology modeling, care delivery, and the proposed impact of telehealth surges on the future of ophthalmology practice.

Conclusion

Recent patient and provider interest in telemedicine, the relaxation of regulatory restrictions, increased remote care reimbursement, and ongoing social distancing practices compel many ophthalmologists to consider virtualizing services.

COVID-19 pandemic from an ophthalmology point of view

Coronavirus disease 2019 (COVID-19) is caused by a highly contagious RNA virus termed as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Ophthalmologists are at high-risk due to their proximity and short working distance at the time of slit-lamp examination. Eye care professionals can be caught unaware because conjunctivitis may be one of the first signs of COVID-19 at presentation, even precluding the emergence of additional symptoms such as dry cough and anosmia. Breath and eye shields as well as N95 masks, should be worn while examining patients with fever, breathlessness, or any history of international travel or travel from any hotspot besides maintaining hand hygiene. All elective surgeries need to be deferred. Adults or children with sudden-onset painful or painless visual loss, or sudden-onset squint, or sudden-onset floaters or severe lid oedema need a referral for urgent care. Patients should be told to discontinue contact lens wear if they have any symptoms of COVID-19. Cornea retrieval should be avoided in confirmed cases and suspects, and long-term preservation medium for storage of corneas should be encouraged. Retinal screening is unnecessary for coronavirus patients taking chloroquine or hydroxychloroquine as the probability of toxic damage to the retina is less due to short-duration of drug therapy. Tele-ophthalmology and artificial intelligence should be preferred for increasing doctor-patient interaction.

Practice Guidelines for Ocular Telehealth-Diabetic Retinopathy, Third Edition

Contributors The following document and appendices represent the third edition of the Practice Guidelines for Ocular Telehealth-Diabetic Retinopathy. These guidelines were developed by the Diabetic Retinopathy Telehealth Practice Guidelines Working Group. This working group consisted of a large number of subject matter experts in clinical applications for telehealth in ophthalmology. The editorial committee consisted of Mark B. Horton, OD, MD, who served as working group chair and Christopher J. Brady, MD, MHS, and Jerry Cavallerano, OD, PhD, who served as cochairs. The writing committees were separated into seven different categories. They are as follows: 1.Clinical/operational: Jerry Cavallerano, OD, PhD (Chair), Gail Barker, PhD, MBA, Christopher J. Brady, MD, MHS, Yao Liu, MD, MS, Siddarth Rathi, MD, MBA, Veeral Sheth, MD, MBA, Paolo Silva, MD, and Ingrid Zimmer-Galler, MD. 2.Equipment: Veeral Sheth, MD (Chair), Mark B. Horton, OD, MD, Siddarth Rathi, MD, MBA, Paolo Silva, MD, and Kristen Stebbins, MSPH. 3.Quality assurance: Mark B. Horton, OD, MD (Chair), Seema Garg, MD, PhD, Yao Liu, MD, MS, and Ingrid Zimmer-Galler, MD. 4.Glaucoma: Yao Liu, MD, MS (Chair) and Siddarth Rathi, MD, MBA. 5.Retinopathy of prematurity: Christopher J. Brady, MD, MHS (Chair) and Ingrid Zimmer-Galler, MD. 6.Age-related macular degeneration: Christopher J. Brady, MD, MHS (Chair) and Ingrid Zimmer-Galler, MD. 7.Autonomous and computer assisted detection, classification and diagnosis of diabetic retinopathy: Michael Abramoff, MD, PhD (Chair), Michael F. Chiang, MD, and Paolo Silva, MD.

Telemedicine for Glaucoma: Guidelines and Recommendations

Background: Glaucoma is the leading cause of irreversible blindness worldwide. Access to glaucoma specialists is challenging and likely to become more difficult as the population ages. Introduction: Using telemedicine for glaucoma (teleglaucoma) has the potential to increase access to glaucoma care by improving efficiency and decreasing the need for long-distance travel for patients. Results: Teleglaucoma programs can be used for screening, diagnostic consultation, and long-term treatment monitoring. Key components of teleglaucoma programs include patient history, equipment, intraocular pressure measurement, pachymetry, anterior chamber imaging/gonioscopy, fundus photography, retinal nerve fiber layer imaging, medical record and imaging software, and skilled personnel. Discussion: Teleglaucoma has tremendous potential to improve patient access to high-quality cost-effective glaucoma care. Conclusions: We have reviewed some special considerations needed to address the complexity of providing guideline-concordant glaucoma care.

Home-based visual field test for glaucoma screening comparison with Humphrey perimeter

Purpose

To present a home-based visual field examination method using a PC monitor or virtual reality glasses and evaluate the reliability of the method by comparing the results with those of the Humphrey perimeter, in order to assess the possibility of glaucoma screening through the Internet.

Materials and methods

Software implementing a supra-threshold algorithm for the central 24° (52 points) of visual field at three threshold levels: 1) -4 db, 2) -8 db, and 3) -12 db, from the age-expected sensitivity was used for the purpose of testing. The software uses the web camera as a "virtual photometer" in order to detect room luminosity and allows self-testing using a computer monitor or virtual reality glasses using an Android smartphone with a 6-inch display. The software includes an expert system to analyze the visual field image and validate the reliability of the results. It also allows the physician to combine the results from two or more tests into a single test in order to achieve higher statistical accuracy of the final result. A total of ten patients, 20 eyes tested×52 points per eye=1,040 visual field test points, were compared point to point to those obtained using the Humphrey perimeter for the same patients, as they appeared randomly and consecutively at the glaucoma department within hours.

Results

Good receiver operating characteristic/area under the curve coefficient was found, ranging from 0.762 to 0.837 (P<0.001). Sensitivity ranged from 0.637 to 0.942, and specificity ranged from 0.735 to 0.497.

Conclusion

The home-based visual field test exhibits a reasonable receiver operating characteristic curve when compared to the Humphrey perimeter, without the need of specialized equipment. The test may be useful for glaucoma screening.