Comparison of the Performance of a Novel, Smartphone-based, Head-mounted Perimeter (GearVision) With the Humphrey Field Analyzer

Development and evaluation of Order of Magnitude (OM): a virtual reality-based visual field analyzer for glaucoma detection

PURPOSE

This study introduces the Order of Magnitude (OM), a cost-effective, indigenous, virtual reality-based visual field analyzer designed for detecting glaucomatous visual field loss.

METHODS

The OM test employs a two-step supra-thresholding algorithm utilizing stimuli of 0.43°diameter (equivalent to Goldmann size III) at low and high thresholds. A comparative analysis was conducted against the Humphrey visual field (HVF) test, considered the gold standard in clinical practice. Participants, including those with glaucoma and normal individuals, underwent comprehensive eye examinations alongside the OM and HVF tests between April and October 2019. Diagnostic sensitivity and specificity of the OM test were assessed against clinical diagnoses made by specialists.

RESULTS

We studied 157 eyes (74 glaucomatous, 83 control) of 152 participants. Results demonstrated a high level of reliability for both OM and HVF tests, with no significant difference observed (P = 0.19, Chi-square test). The sensitivity and specificity of the OM test were found to be 93% (95% CI 86-100%) and 83% (95% CI 72.4-93%), respectively, while the HVF test showed sensitivity and specificity of 98% (95% CI 93.9-100%) and 83% (95% CI 73.9-92.8%), respectively.

CONCLUSION

These findings suggest that the OM test is non-inferior to the reference standard HVF test in identifying glaucomatous visual field loss.

Smartphone Eye Examination: Artificial Intelligence and Telemedicine

Background: The current medical scenario is closely linked to recent progress in telecommunications, photodocumentation, and artificial intelligence (AI). Smartphone eye examination may represent a promising tool in the technological spectrum, with special interest for primary health care services. Obtaining fundus imaging with this technique has improved and democratized the teaching of fundoscopy, but in particular, it contributes greatly to screening diseases with high rates of blindness. Eye examination using smartphones essentially represents a cheap and safe method, thus contributing to public policies on population screening. This review aims to provide an update on the use of this resource and its future prospects, especially as a screening and ophthalmic diagnostic tool. Methods: In this review, we surveyed major published advances in retinal and anterior segment analysis using AI. We performed an electronic search on the Medical Literature Analysis and Retrieval System Online (MEDLINE), EMBASE, and Cochrane Library for published literature without a deadline. We included studies that compared the diagnostic accuracy of smartphone ophthalmoscopy for detecting prevalent diseases with an accurate or commonly employed reference standard. Results: There are few databases with complete metadata, providing demographic data, and few databases with sufficient images involving current or new therapies. It should be taken into consideration that these are databases containing images captured using different systems and formats, with information often being excluded without essential detailing of the reasons for exclusion, which further distances them from real-life conditions. The safety, portability, low cost, and reproducibility of smartphone eye images are discussed in several studies, with encouraging results. Conclusions: The high level of agreement between conventional and a smartphone method shows a powerful arsenal for screening and early diagnosis of the main causes of blindness, such as cataract, glaucoma, diabetic retinopathy, and age-related macular degeneration. In addition to streamlining the medical workflow and bringing benefits for public health policies, smartphone eye examination can make safe and quality assessment available to the population.

Participant Experience Using Novel Perimetry Tests to Monitor Glaucoma Progression

PRCIS

Participant surveys taken after using tablet-based and smart visual function analyzer (SVFA) perimetry tests suggest that patients may prefer novel perimetry tests over traditional visual field machines.

PURPOSE

Compare patient experience using the IMOvifa SVFA and the tablet-based Melbourne Rapid Fields visual field (VF) tests to the Humphrey Field 24-2 Swedish Interactive Threshold Algorithm Standard.

PATIENTS AND METHODS

Prospective observational cohort study on adult participants with diagnoses of glaucoma suspect, ocular hypertension, or glaucoma. Participants attended 2 study visits ~3 months apart. During the first visit, participants were trained to use the 2 novel perimeters, took 1 test on both new devices and the Humphrey Field Analyzer, then were surveyed. Participants received tablets and performed weekly tablet VF tests at home between study visits. At the final study visit, participants re-took the VF tests and completed the same surveys.

RESULTS

Eighty-one participants were surveyed twice. At the baseline survey, participants preferred the SVFA (71.7%) and tablet tests (69.2%) over the Humphrey VF. Most were willing to perform weekly monitoring at home on the SVFA (69.1%) and tablet (75.4%). Participants generally had a "very good" overall experience when testing on the SVFA (71.6%) and tablet (90.1%). At the final visit, fewer participants were willing to test on the tablet daily (23.5% to 9.9%; P = 0.02 for change) and more were willing to test monthly (18.5% to 33.3%; P = 0.03 for change).

CONCLUSION

Users reported a preference for novel VF devices. Overall participant experience using these devices was positive, supporting the feasibility of home monitoring of VFs from an experience perspective.

Test-retest repeatability of the imo binocular random single-eye test and Humphrey monocular test in patients with glaucoma

PURPOSE

To evaluate the reproducibility of the imo binocular random single-eye test (BRSET) and Humphrey Field Analyzer (HFA) monocular test in patients with glaucoma.

STUDY DESIGN

Retrospective observational study.

METHODS

We measured the visual fields (VF) of patients with glaucoma using the BRSET and HFA. All tests were repeated two months later. Mean sensitivity (MS), mean deviation (MD), sensitivity at each test location, and reliability indices were compared between the test days. Wilcoxon signed-rank test, interclass correlation coefficient (ICC), correlation coefficients, and Bland-Altman plots were generated for analysis.

RESULTS

We analyzed the VFs of 46 patients with glaucoma. There were no test-retest differences for MS and MD, and ICCs were > 0.9 for MS and MD in both perimeters. Inter-test correlations for MS and MD were high. The limits of agreement (LoAs) (lower, upper limit) between test days for MS were (- 3.4, 4.0) for BRSET and (-3.3, 3.0) for HFA. The LoA for MD was (- 3.3, 3.8) for BRSET and (- 3.2, 2.9) for HFA. Sensitivity at each testing location was more variable between testing days for BRSET than for HFA. For reliability indices, LoAs between testing days were wider for BRSET than for HFA.

CONCLUSION

The imo BRSET showed similar reproducibility to HFA in MS and MD. However, sensitivity at each test location varied more for BRSET than for HFA. Further studies are needed to verify the reproducibility of the imo BRSET.

Comparison of a New Head Mount Virtual Reality Perimeter (C3 Field Analyzer) With Automated Field Analyzer in Neuro-Ophthalmic Disorders

BACKGROUND

Automated perimetry in neurologically disabled patients is a challenge. We have devised a patient-friendly virtual reality perimeter, the C3 field analyzer (CFA). We aim to assess the utility of this as a visual field-testing device in neuro-ophthalmic patients for screening and monitoring.

METHODS

Neuro-ophthalmic patients and controls were selected to participate in the study between September and December 2018. They randomly underwent either the CFA or automated field analyzer (HFA) first followed by the other in an undilated state. The CFA results were compared with the HFA, and the correlation of the pattern of the field defect was assessed by an independent masked physician.

RESULTS

In total, 59 eyes of 33 neuro-ophthalmic patients (cases) and another 95 normal individuals (controls) were enrolled. CFA was found to have greater proportion of reliable fields (81.4%) than HFA (59.3%) ( P = 0.009). There were less false negatives ( P < 0.001) and more false positives in CFA ( P < 0.001) among neuro-ophthalmic patients compared with controls. Among neuro-ophthalmology patients, the number of fixation losses was greater with CFA ( P < 0.001), whereas false negatives were greater in HFA ( P < 0.001). On assessing the pattern of the field defects, we found that there was almost 70% correlation of CFA with HFA. Moreover, in classical neurological fields such as hemianopia, the correlation was 87.5%.

CONCLUSIONS

The CFA seems to correlate well with HFA in classic neurological fields such as hemianopias and may serve as an alternative in patients unable to perform a standard automated perimetry. Further developments are currently underway to incorporate threshold testing.

Teleglaucoma Using a New Smartphone-Based Tool for Visual Field Assessment

PRCIS

COVID-19 underlines the importance of telemedical diagnostics. The smartphone-based campimetry (Sb-C) is a newly developed digital application allowing visual field testing using a head-mounted device and a smartphone. It enables visual field screening remotely from a clinic.

BACKGROUND

Sb-C is a newly developed tool for functional ophthalmic diagnosis. This study aimed to examine the comparability of the Sb-C and Octopus 900 to ensure ophthalmological care in times of social distancing.

METHODS

Total 93 eyes were included in the study. After an ophthalmological examination, the visual field was tested by the Octopus program G1 and by the smartphone-based campimeter. The Sb-C was performed using VR glasses and an iPhone 6. The software Sb-C was downloaded and installed as SmartCampiTracker app and is examining the 30-degree visual field with 59 test positions corresponding to the G pattern of Octopus G1. Sensitivities were recorded and saved on the app. In addition, test-retest reliability was tested on 6 ophthalmologically healthy participants.

RESULTS

The group comprised 48 women and 45 men (mean age: 62.52±12.2 y) including 19 controls, 17 patients with ocular hypertension, 11 preperimetric glaucomas, and 46 perimetric glaucomas. The mean sensitivity (MS) of all points of G1 perimetry was 23.13 dB (95% CI, 22.08-24.18). The MS of the Sb-C was 21.23 dB (95% CI, 20.37-22.08). The correlation between the mean MS measured by G1 perimetry and the Sb-C was strong ( r =0.815, P <0.05). The test-retest reliability showed a correlation of r =0.591 ( P <0.05) .

CONCLUSIONS

With some technical adjustments, the Sb-C shows promise for screening glaucoma and monitoring disease progression remotely from an ophthalmologic clinic.

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.