Predicting Global Test-Retest Variability of Visual Fields in Glaucoma

Diagnostic performance of pupil perimetry in detecting hemianopia under standard and virtual reality viewing conditions

PURPOSE

To determine the diagnostic performance and reliability of two pupil perimetry (PP) methods in homonymous hemianopia.

METHODS

This cross-sectional monocenter cohort study performed gaze-contingent flicker PP (gcFPP) and a virtual reality version of gcFPP (VRgcFPP) twice on separate occasions in all patients suffering from homonymous hemianopia due to neurological impairment. The main outcomes were (1) test accuracy and (2) test-retest reliability: (1) was measured through area under the receiver operating characteristics curve (AUC) calculation of (VR)gcFPP results with comparators being SAP and healthy controls, respectively; (2) was evaluated by comparing tests 1 and 2 of both methods within patients.

RESULTS

Both gcFPP and VRgcFPP were performed in 15 patients (12 males, MAge = 57, SDAge = 15) and 17 controls (6 males, MAge = 53, SDAge = 12). Mean test accuracy was good in separating damaged from intact visual field regions (gcFPP: Mauc = 0.83, SDauc = 0.09; VRgcFPP: Mauc = 0.69, SDauc = 0.13) and in separating patients from controls (gcFPP: Mauc = 0.92, SDauc = 0.13; VRgcFPP: Mauc = 0.96, SDauc = 0.15). A high test-retest reliability was found for the proportion intact versus damaged visual field (gcFPP: r = 0.95, P < .001, VRgcFPP: r = 1.00, P < .001).

CONCLUSIONS

Overall, these results can be summarized as follows: (1) the comparison of pupil response amplitudes between intact versus damaged regions per patient indicate that gcFPP allows for cleaner imaging of intact versus damaged visual field regions than VRgcFPP, (2) the comparisons of average differences in intact versus damaged amplitudes between patients and controls demonstrate high diagnostic performance of both gcFPP and VRgcFPP, and (3) the test-retest reliabilities confirm that both gcFPP and VRgcFPP reliably and consistently measure defects in homonymous hemianopia. KEY  MESSAGES: What is known Standard automated perimetry is the current gold standard for visual field examination, but not always suited for the evaluation of the VF in neurologically impaired patients. Pupil perimetry consists of the measurement of pupillary responses to light stimuli as a measure of visual sensitivity. What is new This study reports the highest diagnostic accuracy of pupil perimetry so far in patients with homonymous hemianopia. Gaze-contingent flicker pupil perimetry reliably and consistently measures defects in homonymous hemianopia under standard and virtual reality viewing conditions.

Repeatability of a Virtual Reality Headset Perimeter in Glaucoma and Ocular Hypertensive Patients

Purpose

The VisuALL S is an automated, static threshold, virtual reality-based perimeter for mobile evaluation of the visual field. We examined same-day and 3-month repeatability.

Methods

Adult participants with a diagnosis of glaucoma or ocular hypertension underwent two VisuALL 24-2 Normal T- Full threshold strategy tests at baseline and one additional exam at 3 months for each eligible eye. Spearman, intraclass correlation coefficients (ICCs), and Bland-Altman plots were used to assess the correlation of individual point sensitivities and mean deviation (MD) among three tests.

Results

Eighty-eight eyes (44 participants) were included. Average age was 68.1 ± 14.3 years, and 60.7% were male. VisuALL MD was highly correlated between tests (intravisit: r = 0.89, intervisit: r = 0.82; P < 0.001 for both). Bland-Altman analysis showed an average difference in intravisit MD of -0.67 dB (95% confidence interval [CI], -6.04 to 4.71 dB) and -0.15 dB (95% CI, -8.04 to 7.73 dB) for intervisit exams. Eight-five percent of pointwise intravisit ICCs were above 0.75 (range, 0.63 to 0.93), and 65% of pointwise intervisit ICCs were above 0.75 (range, 0.55 to 0.91).

Conclusions

VisuALL demonstrated high correlation of MD between tests and good repeatability for individual point sensitivities among three tests in 3 months, except at the points around the blind spot and superiorly.

Translational Relevance

The preliminary reproducibility results for VisuALL are encouraging. Its portable design makes it a potentially useful tool for patients with glaucoma, enabling more frequent assessments both at home and in clinical settings.

Reliability of Visual Field Testing in a Telehealth Setting Using a Head-Mounted Device: A Pilot Study

PRCIS

Monitoring visual fields (VFs) through virtual reality devices proved to have good inter-test and test-retest reliability, as well as easy usability, when self-administered by individuals with and without VF defects in a remote setting.

PURPOSE

To assess the reliability of remote, self-administered VF monitoring using a virtual reality VF (VRVF) device in individuals without ocular disease and with stable VF defects.

MATERIALS AND METHODS

Individuals without ocular disease and with stable defects were recruited. All participants had a baseline standard automated perimetry (SAP) test. Participants tested remotely on a VRVF device for 4 weeks (examinations V 1 , V 2 , V 3 , and V 4 ), with the last 3 unassisted. The mean sensitivities of VRVF results were compared with each other and to SAP results for reliability.

RESULTS

A total of 42 eyes from 21 participants were tested on the VRVF device. Participants tested consistently although external factors impacted outcomes. VRVF results were in reasonable agreement with the baseline SAP. Examinations performed by the cohort with stable defects evinced better agreement with SAP examinations (V2, P = 0.79; V3, P = 0.39; V4, P = 0.35) than those reported by the cohort without ocular disease (V2, P = 0.02; V3, P = 0.15; V4, P = 0.22), where the null hypothesis is that the instruments agree. Fixation losses were high and variable in VRVF examinations compared with those of SAP, particularly in certain test takers. Participants considered the device comfortable and easy to use.

CONCLUSIONS

Self-administered, remote VF tests on a VRVF device showed satisfactory test-retest reliability, good inter-test agreement with SAP, and acceptability by its users. External factors may impact at-home testing and age and visual impairment may hinder fixation. Future studies to expand the sample size and understand inconsistencies in fixation losses are recommended.

Predicting 60-4 visual field tests using 3D facial reconstruction

BACKGROUND

Despite, the potential clinical utility of 60-4 visual fields, they are not frequently used in clinical practice partly, due to the purported impact of facial contour on field defects. The purpose of this study was to design and test an artificial intelligence-driven platform to predict facial structure-dependent visual field defects on 60-4 visual field tests.

METHODS

Subjects with no ocular pathology were included. Participants were subject to optical coherence tomography, 60-4 Swedish interactive thresholding algorithm visual field tests and photography. The predicted visual field was compared with observed 60-4 visual field results in subjects. Average and point-specific sensitivity, specificity, precision, negative predictive value, accuracy, and F1-scores were primary outcome measures.

RESULTS

30 healthy were enrolled. Three-dimensional facial reconstruction using a convolution neural network (CNN) was able to predict facial contour-dependent 60-4 visual field defects in 30 subjects without ocular pathology. Overall model accuracy was 97%±3% and 96%±3% and the F1-score, dependent on precision and sensitivity, was 58%±19% and 55%±15% for the right eye and left eye, respectively. Spatial-dependent model performance was observed with increased sensitivity and precision within the far inferior nasal field reflected by an average F1-score of 76%±20% and 70%±29% for the right eye and left eye, respectively.

CONCLUSIONS

This pilot study reports the development of a CNN-enhanced platform capable of predicting 60-4 visual field defects in healthy controls based on facial contour. Further study with this platform may enhance understanding of the influence of facial contour on 60-4 visual field testing.

Comparison of Perimetric Outcomes from a Tablet Perimeter, Smart Visual Function Analyzer, and Humphrey Field Analyzer

PURPOSE

The tablet-based Melbourne Rapid Fields (MRF) visual field (VF) test and the IMOvifa Smart Visual Function Analyzer (SVFA) are portable perimeters that may allow for at-home monitoring and more frequent testing. We compared tablet and SVFA results with outputs from the Humphrey Field Analyzer (HFA) 24-2 Swedish Interactive Threshold Algorithm Standard program.

DESIGN

Observational cross-sectional study.

SUBJECTS

Adult participants with a diagnosis of glaucoma, suspected glaucoma, or ocular hypertension seen in the Massachusetts Eye and Ear glaucoma clinic were enrolled. All participants were reliable and experienced HFA testers.

METHODS

Participants were tested with the SVFA and HFA. The study staff also trained participants on the MRF tablet with instructions to take weekly tests at home for 3 months. Visual field results from the 3 devices were compared.

MAIN OUTCOME MEASURES

Mean deviation (MD), pattern standard deviation (PSD), reliability parameters, and point sensitivity.

RESULTS

Overall, 79 participants (133 eyes) with a mean age of 61 ± 13 years (range, 26-79 years) were included; 59% of the participants were female, and the mean HFA MD was -2.7 ± 3.9 dB. The global indices of MD and PSD did not significantly vary between HFA and the 2 novel devices, except that the tablet VF reported a 0.6 dB higher PSD compared with HFA. However, tablet and SVFA sensitivities significantly differed from those of the HFA at 36 and 39 locations, respectively, out of 52 locations. Relative to HFA, the tablet overestimated light sensitivity in the nasal field while underestimating the temporal field. The SVFA generally underestimated light sensitivity, but its results were more similar to HFA results compared with the tablet.

CONCLUSIONS

Although average MD values from the 2 novel devices suggest that they provide similar results to the HFA, point-by-point comparisons highlight notable deviations. Differences in specific point sensitivity values were significant, especially between the tablet and the other 2 devices. These differences may in part be explained by differences in the devices' normative databases as well as how MD is calculated. However, the tablet had substantial differences based on location, indicating that the tablet design itself may be responsible for differences in local sensitivities.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Relationship between the Macular Microvasculature and Central Visual Field Sensitivity in Patients with Advanced Glaucoma

PURPOSE

To evaluate the relationship between central visual field sensitivity (cVFS) and the structural parameters in patients with advanced glaucoma.

DESIGN

Cross-sectional study.

METHODS

In total, 226 eyes of 226 patients with advanced glaucoma were classified into the "minor central defect" (mean deviation on 10-2 visual field test [MD10] > -10 dB) and "significant central defect" (MD10 ≤ -10 dB) groups. We examined the structural parameters using RTVue OCT and angiography, including the retinal nerve fiber layer, ganglion cell complex, peripapillary vessel density (VD), and superficial and deep macular VD (mVD). The assessment of cVFS included MD10 and the mean deviation of the central 16 points on the 10-2 VF test (MD16). We used Pearson correlation and segmented regression to assess the global and regional relationships between the structural parameters and cVFS.

MAIN OUTCOME MEASURES

Correlation between structural parameters and cVFS.

RESULTS

In the minor central defect group, the best global correlations existed between the superficial macular and parafoveal mVD and MD16 (r = 0.52 and 0.54, P < 0.001). In the significant central defect group, superficial mVD best correlated with MD10 (r = 0.47, P < 0.001). Segmented regression between superficial mVD and cVFS revealed no breakpoint was found as MD10 declined, but a breakpoint was identified at -5.95 dB for MD16, which was statistically significant (P < 0.001). The regional correlations between the grid VD and sectors of the central 16 points were significant (r = 0.20-0.53, P= 0.010 ∼P < 0.001).

CONCLUSIONS

The fair global and regional relationships between mVD and cVFS suggest that mVD may be beneficial for monitoring cVFS in patients with advanced glaucoma.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Combined Model of OCT Angiography and Structural OCT Parameters to Predict Paracentral Visual Field Loss in Primary Open-Angle Glaucoma

PURPOSE

To assess a model combining OCT angiography (OCTA) and OCT parameters to predict the severity of paracentral visual field (VF) loss in primary open-angle glaucoma (POAG).

DESIGN

Cross-sectional study.

PARTICIPANTS

Forty-four patients with POAG and 42 control subjects underwent OCTA and OCT imaging with a swept-source OCT device.

METHODS

The circumpapillary microvasculature was quantified for vessel density (cpVD) and flow (cpFlow) after delineation of Bruch's membrane opening and removal of large vessels. Retinal nerve fiber layer thickness (RNFLT) and Bruch's membrane opening-minimum rim width (BMO-MRW) were measured from structural OCT. Paracentral total deviation (PaTD) was defined as the average of the total deviation values within the central 10 degrees on Humphrey VF testing (24-2) for upper and lower hemifields. The OCT and OCTA parameters were measured in the affected hemisphere corresponding to the hemifield with lower PaTD for POAG patients. Models were created to predict affected PaTD based on RNFLT alone; RNFLT and BMO-MRW; OCTA alone; or RNFLT, BMO-MRW and OCTA parameters. The models were compared using coefficient of determination (r2) and Bayesian information criterion (BIC) score. Bayesian information criterion decrease of ≥6 indicates strong evidence for model improvement.

MAIN OUTCOME MEASURES

Performance of models containing OCT and OCTA parameters in predicting PaTD.

RESULTS

Patients with POAG and controls were similar in age and sex (65.9 ± 9.5 years and 38.4% male overall, P ≥ 0.56 for both). Average RNFLT, minimum RNFLT, average BMO-MRW, minimum BMO-MRW, cpVD, and cpFlow were all significantly lower (all P < 0.001) in the affected hemisphere in patients with POAG than in controls. In patients with POAG, the average mean deviation was -4.33 ± 3.25 dB; the PaTD of the affected hemifield averaged -4.55 ± 5.26 dB and correlated significantly with both OCTA and structural OCT parameters (r ≥ 0.43, P ≤ 0.004 for all). The model containing RNFLT, BMO-MRW, and OCTA parameters was superior in predicting affected PaTD (r2 = 0.47, BIC = 290.7), with higher r2 and lower BIC compared with all 3 other models.

CONCLUSIONS

A combined model of OCTA and structural OCT parameters can predict the severity of paracentral VF loss of the affected hemifield, supporting clinical utility of OCTA in patients with POAG with paracentral VF loss.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Perimetric Comparison Between the IMOvifa and Humphrey Field Analyzer

PRCIS

IMO visual function analyzer (IMOvifa), a binocular perimeter, has similar output to the Humphrey Field Analyzer (HFA), but reduced the measurement time.

PURPOSE

The purpose of this study is to evaluate the performance of IMOvifa, a perimeter that performs binocular visual field (VF) testing, and to compare its results with standard automated perimetry.

METHODS

All patients underwent HFA 24-2 SITA-Fast and IMOvifa 24-2 AIZE-Rapid on the same day. Mean deviation (MD), pattern SD (PSD), foveal threshold, and visual field index (VFI) were compared between the 2 perimeters using Wilcoxon signed-rank tests, Pearson correlation, and Bland-Altman plot. Measurement time for performing VF for both eyes was also collected for each device.

RESULTS

In this cross-sectional study, 138 eyes (including 25 healthy, 48 glaucoma suspects, and 65 primary open angle glaucoma) of 69 patients were evaluated. Measurement time was significantly faster for IMOvifa compared with HFA (256 vs. 419 s, P <0.001). No significant differences were seen in MD and VFI between HFA and IMOvifa (both P >0.05). Significant differences were seen in mean PSD 3.2 (2.7, 3.6) dB for HFA versus 4.1 (3.5, 4.6) for IMOvifa ( P <0.001), and foveal threshold 33.9 (33.1, 34.6) dB for HFA versus 30.6 (29.3, 31.9) dB for IMOvifa ( P <0.001). Pearson r was strong for MD ( r =0.90, P <0.001), PSD ( r =0.78, P <0.001), and VFI ( r =0.94, P <0.001). The mean difference (95% limits of agreement) was -0.1 (-3.8, 3.5) dB for MD, -0.4 (-3.4, 2.5) dB for PSD, and 0.1 (-8.9, 9.1) dB for VFI, respectively.

CONCLUSIONS

IMOvifa reduced measurement time by 39%. MD, PSD, and VFI values for IMOvifa showed good agreement with HFA SITA-Fast strategy. This perimeter reduced fatigue for both patient and examiner. Additional studies are needed to determine whether it will be useful for routine VF testing.

Improving event-based progression analysis in glaucomatous visual fields

Glaucoma is a progressive optic neuropathy with characteristic changes to the optic nerve head and the visual field (VF). Detecting progression of VF damage with Standard Automated Perimetry (SAP) is of paramount importance for clinical care. One common approach to detecting progression is to compare each new VF test to a baseline SAP test (event analysis). This comparison is made difficult by the test–retest variability of SAP, which increases with the level of VF damage, and the limited range of measurement, meaning that damage cannot be assessed below a certain level. We performed a prospective international multi-centre data collection of SAP data on 90 eyes from 90 people with glaucoma and different levels of VF damage over a short period of time (6 tests in 60 days). Data were collected using a fundus tracked perimeter (Compass, CenterVue). We used these data (minus the first test) to develop an improved event analysis that accounts for both the change in variability with damage and the lower bound on the measurement imposed by SAP. Using simulations, we show that our approach is more sensitive compared to previously developed methods, especially in the case of advanced glaucoma, while retaining similar specificity.