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.

The structure-function relationship between multifocal pupil perimetry and retinal nerve fibre layer in glaucoma.

BACKGROUND: Multifocal pupillographic objective perimetry (mfPOP) is a novel method for assessing functional change in diseases like glaucoma. Previous research has suggested that, in contrast to the pretectally-mediated melanopsin response of intrinsically photosensitive retinal ganglion cells, mfPOP responses to transient onset stimuli involve the extrastriate cortex, and thus the main visual pathway. We therefore investigate the correlation between peripapillary retinal nerve fibre layer (pRNFL) thickness and glaucomatous visual field changes detected using mfPOP. Parallel analyses are undertaken using white on white standard automated perimetry (SAP) for comparison. METHODS: Twenty-five glaucoma patients and 24 normal subjects were tested using SAP, 3 mfPOP variants, and optical coherence tomography (OCT). Arcuate clusters of the SAP and mfPOP deviations were weighted according to their contribution to published arcuate divisions of the retinal nerve fibre layer. Structure-function correlation coefficients (r) were computed between pRNFL clock-hour sector thickness measurements, and the local visual field sensitivities from both SAP and mfPOP. RESULTS: The strongest correlation was observed in the superior-superotemporal disc sector in patients with worst eye SAP MD < -12 dB: r = 0.93 for the mfPOP LumBal test (p < 0.001). Correlations across all disc-sectors were strongest in these same patients in both SAP and mfPOP: SAP r = 0.54, mfPOP LumBal r = 0.55 (p < 0.001). In patients with SAP MD ≥ -6 dB in both eyes, SAP correlations across all sectors were higher than mfPOP; mfPOP correlations however, were higher than SAP in more advanced disease, and in normal subjects. CONCLUSIONS: For both methods the largest correlations with pRNFL thickness corresponded to the inferior nasal field of more severely damaged eyes. Head-to-head comparison of mfPOP and SAP showed similar structure-function relationships. This agrees with our recent reports that mfPOP primarily stimulates the cortical drive to the pupils.

Improving the robustness of the Sequentially Optimized Reconstruction Strategy (SORS) for visual field testing.

Perimetry, or visual field test, estimates differential light sensitivity thresholds across many locations in the visual field (e.g., 54 locations in the 24-2 grid). Recent developments have shown that an entire visual field may be relatively accurately reconstructed from measurements of a subset of these locations using a linear regression model. Here, we show that incorporating a dimensionality reduction layer can improve the robustness of this reconstruction. Specifically, we propose to use principal component analysis to transform the training dataset to a lower dimensional representation and then use this representation to reconstruct the visual field. We named our new reconstruction method the transformed-target principal component regression (TTPCR). When trained on a large dataset, our new method yielded results comparable with the original linear regression method, demonstrating that there is no underfitting associated with parameter reduction. However, when trained on a small dataset, our new method used on average 22% fewer trials to reach the same error. Our results suggest that dimensionality reduction techniques can improve the robustness of visual field testing reconstruction algorithms.

Validation of a Wearable Virtual Reality Perimeter for Glaucoma Staging, The NOVA Trial: Novel Virtual Reality Field Assessment.

Purpose: Compare estimated sensitivities of SITA-Standard to the RATA-Standard algorithm of the Radius virtual reality perimeter (VRP), and measure concordance in glaucoma staging. Methods: One hundred adult glaucoma patients-half with suspect or mild glaucoma, and half with moderate or severe-from five clinics performed four 24-2 visual field tests during a single visit, two with the Humphrey Field Analyzer (HFA) and two with Radius, in randomized order: HRHR or RHRH. Only one eye was tested per participant. We used the Wilcoxon rank sum test with Bonferroni correction to compare distributions of estimated sensitivities across all 54 test locations over the 15 to 40 dB measurement range of the Radius. Weighted kappa measured concordance in glaucoma staging between two masked glaucoma experts using Medicare definitions of severity. Results: A total of 62 OD and 38 OS eyes were tested. Estimated sensitivities for SITA-Standard and RATA-Standard were not significantly different for OD, but were for OS-likely because of SITA-Standard OD and OS being significantly different in our sample, but not for RATA-Standard. Low agreement was observed between 15 to 22 dB. Concordance in glaucoma staging was high for both graders: kappa = 0.91 and kappa = 0.93. Average test duration was 298 seconds for RATA-Standard and 341 seconds for SITA-Standard. The correlation in mean deviation was 0.94. Conclusions: Estimated sensitivities of RATA-Standard are comparable to SITA-Standard between 23 to 40 dB with high concordance in glaucoma staging. Translational Relevance: Radius VRP is statistically noninferior to HFA when staging glaucoma using Medicare definitions.

Detección y caracterización de defectos del campo visual mediante perimetría Octopus en glaucoma congénito primario / Detection and characterisation of visual field defects using Octopus perimetry in congenital glaucoma

Detectar y caracterizar los defectos del campo visual (CV) mediante perimetría Octopus en pacientes con glaucoma congénito primario (GCP) y determinar la calidad y duración del CV. Material y métodos: Se incluyeron 88 ojos de 70 pacientes diagnosticados de GCP. Las evaluaciones se realizaron con un Octopus 900 y cada ojo se evaluó con el algoritmo de perimetría orientada por tendencias (G-TOP). Se recogieron datos cuantitativos de CV: datos de calidad (respuestas falsa positiva y negativa, y duración del tiempo) y resultados de desviación media (DM) y raíz cuadrada de la varianza de pérdida (sLV). También se recogieron datos cualitativos: presencia de defectos difusos y localizados, hemicampo afectado y grado de defectos utilizando la clasificación de Aulhorn y Karmeyer. Se analizaron las correlaciones entre los resultados perimétricos y las variables clínicas. Resultados: La mediana de edad fue de 11 (8-17) años. El 65,9% (58/88) de los ojos con GCP presentaban defectos de CV. Se observaron defectos difusos en 10/58 ojos (16,94%) (DM media=23,92 [DE: 2,52]) dB) y defectos localizados en 48/58 ojos (82,75%). El defecto más frecuente fue el escotoma incipiente paracentral (n=15), el escalón nasal (n=8), el defecto arciforme añadido (n=2), el semianular (n=13) y el defecto concéntrico con isla central (n=9). El hemicampo visual afectado con mayor frecuencia fue el inferior. La duración media de la prueba fue de 2min 12s (DE: 21,6s). Los valores MD y sLV se correlacionaron con la agudeza visual mejor corregida, la relación excavación/disco y el número de cirugías de glaucoma (todas p<0,001). Conclusión: Se identificó un alto número de defectos difusos y localizados utilizando la perimetría Octopus en pacientes con GCP. El defecto más frecuente fue el escotoma paracentral, y el hemicampo inferior fue el más afectado.(AU)

Purpose: To detect and characterise visual field (VF) defects using static Octopus perimetry in patients with primary congenital glaucoma (PCG) and to determine VF quality and time duration. Material and methods: Eighty-eight eyes of 70 patients diagnosed with PCG were included. Assessments were performed using an Octopus 900 and each eye was assessed with the tendency-oriented perimetry (G-TOP) algorithm. Quantitative VF data were collected: quality data (false positive and negative response, and time duration) and results of mean deviation (MD) and square root of loss variance (sLV). Qualitative data were collected: the presence of diffuse and localized defects, the affected hemifield and grade of defects using the Aulhorn and Karmeyer classification. Correlations between perimetric results and clinical variables were analysed. ResultsMedian age was 11 (8-17) years. 65.9% (58/88) of PCG eyes showed VF defects. Diffuse defects were observed in 10/58 eyes (16.94%) (mean MD=23.92 [SD: 2.52]) dB) and localized defects in 48/58 eyes (82.75%). The most frequent defect was spot-like/stroke-like/incipient paracentral scotoma (n=15), nasal step (n=8), adding arcuate defect (n=2), half ring-shaped (n=13) and concentric defect with a central island (n=9). And the most frequent affected visual hemifield was inferior hemifield. Mean test duration was 2min 12s (SD: 21.6s). MD and sLV values were correlated with best corrected visual acuity (BCVA), cup to disc ratio and number of antiglaucoma surgeries (all P<.001). Conclusion: A high number of diffuse and localized defects were identified using Octopus perimetry in PCG patients. The most frequent defect was paracentral scotoma and inferior hemifield was the most affected.(AU)

Hemifield-based analysis of pattern electroretinography in normal subjects and patients with preperimetric glaucoma.

This prospective cross-sectional study investigated the visual function of preperimetric glaucoma (PPG) patients based on hemifield (HF) pattern electroretinogram (PERG) amplitudes. Thirty-two (32) normal subjects and 33 PPG patients were enrolled in control and PPG groups, respectively. All of the participants had undergone full ophthalmic examinations, including spectral-domain optical coherence tomography (SD-OCT), visual field (VF) examination and pattern electroretinography (PERG). The PERG parameters along with the HF ratios of SD-OCT and PERG were compared between the control and PPG groups. Pairwise Pearson's correlation coefficients and linear regression models were fitted to investigate the correlations. The PERG N95 amplitudes were significantly lower in the PPG group (P < 0.001). The smaller/larger HF N95 amplitude ratio of the PPG group was found to be smaller than that of the control group (0.73 ± 0.20 vs. 0.86 ± 0.12; P = 0.003) and showed positive correlations with affected HF average ganglion cell-inner plexiform layer (GCIPL) thickness (r = 0.377, P = 0.034) and with average GCIPL thickness (r = 0.341, P = 0.005). The smaller/larger HF N95 amplitude ratio did not significantly change with age (ß = - 0.005, P = 0.195), whereas the full-field N95 amplitude showed a negative correlation with age (ß = - 0.081, P < 0.001). HF analysis of PERG N95 amplitudes might be particularly useful for patients with early glaucoma.

Understanding and identifying visual field progression.

Detecting deterioration of visual field sensitivity measurements is important for the diagnosis and management of glaucoma. This review surveys the current methods for assessing progression that are implemented in clinical devices, which have been used in clinical trials, alongside more recent advances proposed in the literature. Advice is also offered to clinicians on what they can do to improve the collection of perimetric data to help analytical progression methods more accurately predict change. This advice includes a discussion of how frequently visual field testing should be undertaken, with a view towards future developments, such as digital healthcare outside the standard clinical setting and more personalised approaches to perimetry.

Predicting the Extent of Damage in the Humphrey Field Analyzer 24-2 Visual Fields Using 10-2 Test Results in Patients With Advanced Glaucoma.

Purpose: To predict Humphrey Field Analyzer 24-2 test (HFA 24-2) results using 10-2 results. Methods: A total of 175 advanced glaucoma eyes (175 patients) with HFA 24-2 mean deviation (MD24-2) of < -20 dB were prospectively followed up for five years using HFA 10-2 and 24-2 (twice and once in a year, respectively). Using all the HFA 24-2 and 10-2 test result pairs measured within three months (350 pairs from 85 eyes, training dataset), a formula to predict HFA 24-2 result using HFA 10-2 results was constructed using least absolute shrinkage and selection operator regression (LASSO). Using 90 different eyes (testing dataset), the absolute differences between the actual and LASSO-predicted MD24-2 and that between the slopes calculated using five actual and LASSO-predicted MD24-2 values, were adopted as the prediction error. Similar analyses were performed for the mean total deviation values (mTD) of the superior (or inferior) hemifield [hemi-mTDsup.24-2(-hemi-mTDinf.24-2)]. Results: The prediction error for the LASSO-predicted MD24-2 and its slope were 2.98 (standard deviation [SD] = 1.90) dB and 0.32 (0.33) dB/yr, respectively. The LASSO-predicted hemi-mTDsup.24-2 (hemi-mTDinf.24-2), and its slope were 3.02 (2.89) and 3.76 (2.72) dB, and 0.37 (0.41) and 0.44 (0.38) dB/year, respectively. These prediction errors were within two times SD of repeatability of the simulated stable HFA 24-2 VF parameter series. Conclusions: HFA 24-2 results could be predicted using the paired HFA 10-2 results with reasonable accuracy using LASSO in patients with advanced glaucoma. Translational Relevance: It is useful to predict HFA24-2 test from HFA10-2 test, when the former is not available, in advanced glaucoma.

Using the Amsler Grid Test for Age-Related Macular Degeneration Screening.

Objectives: To evaluate the use of the Amsler grid test (AGT) in screening for age-related macular degeneration (AMD), one of the most common causes of blindness, in primary healthcare settings. Materials and Methods: The AGT was applied to 700 eyes of 355 people aged 50 and over who applied to a family health center in Ankara and had no eye complaints. The test was considered positive if the lines on the AGT card were seen as broken or curved, there was a difference in shape or size between the squares, or a color change or blurring was described in any area. An ophthalmologist was consulted if the AGT was positive in one or both eyes. Patients considered suitable by ophthalmologists were evaluated with optical coherence tomography. AGT results were compared with ophthalmologist examination and tomography findings in terms of AMD detection. Results: The AGT was positive in 97 (13.9%) and negative in 603 (86.1%) out of 700 eyes included in the study. A total of 184 eyes, 79 with a positive AGT and 105 eyes with a negative test, were evaluated by an ophthalmologist. As a result of examinations and tests performed by ophthalmologists, AMD was detected in a total of 67 eyes: 42 of 79 eyes with positive AGT and 25 of 105 eyes with negative AGT but referred to an ophthalmologist for different reasons. In our study, the AGT had 62.7% sensitivity and 68.4% specificity. Conclusion: The AGT is an inexpensive and easily applicable test. Although moderate sensitivity and specificity were found in our study; further studies are needed to evaluate the suitability of its use for AMD screening in primary care with limited facilities.

Mechanisms of cone sensitivity loss in retinitis pigmentosa.

PURPOSE: To explore the mechanisms of cone sensitivity loss in retinitis pigmentosa by combining two-colour perimetry with threshold versus intensity (tvi) testing. METHODS: Seven subjects with autosomal recessive retinitis pigmentosa and 10 normal subjects were recruited and underwent perimetric testing of one eye using 480- and 640-nm Goldman size V targets presented under scotopic conditions (no background illumination) and against a white background ranging in luminance from -1.5 to 2 log cd m-2 in 0.5 log cd m-2 steps. Data were fitted with tvi functions of the form logT = logT0 + log ((A + A0)/A0)n, where T is the threshold, T0 is the absolute threshold, A is the background intensity, A0 is the 'dark-light' constant and n is a gain constant. RESULTS: Reliable tvi functions could not be obtained within the region of the visual field corresponding to loss of the ellipsoid zone on optical coherence tomography. At fixation, changes in both T0 and A0 were observed, consistent with a d1 mechanism loss, which resulted in an upwards and rightwards shift of the tvi function. Losses at [±3°, ±3°] demonstrated changes in T0, consistent with a d3 mechanism loss, resulting in an upwards translation of the tvi curve. CONCLUSIONS: Although the absolute cone threshold was elevated at each location, shifts in the tvi function (so-called d1 mechanism loss) at fixation minimise threshold elevation in the presence of white adapting backgrounds, such as those typically employed in standard two-colour perimetry. At more peripheral testing locations, changes in threshold occurred independent of background luminance (so-called d3 mechanism loss). These findings suggest that backgrounds which selectively adapt rods while maintaining cones at, or near, absolute threshold may be preferable to conventional two-colour perimetry for assessing loss of cone sensitivity, especially at the point of fixation.

Relationship between residual visual field and full-field stimulus testing in patients with late-stage retinal degenerative diseases.

This study aimed to investigate how the extent and central/peripheral location of the residual visual field (VF) in patients with late-stage inherited retinal diseases (IRDs) are related to retinal sensitivity detected using full-field stimulus testing (FST). We reviewed the results of Goldmann perimetry and FST from the medical records of patients with IRDs whose VF represents central (within 10°) and/or peripheral islands, or undetectable. In total, 19 patients (19 eyes) were analyzed in this study. The median value of residual VF area was 1.38%. The median values of rod and cone sensitivities were - 14.9 dB and 7.4 dB, respectively. Patients with only the peripheral island (- 33.9 dB) had better median rod sensitivity than other groups (only central, - 18.9 dB; both, - 3.6 dB). VF area significantly correlated with rod sensitivity (r = - 0.943, p = 0.005) in patients with only peripheral island, but not with cone sensitivity. Peripheral VF islands were significant contributors to FST results, especially rod sensitivity. With reduced or loss of central vision, the extent of residual peripheral VF significantly affected rod sensitivity, suggesting that FST can be useful in quantitatively estimating the overall remaining vision in patients with late-stage IRD.

Frontloading visual field tests detect earlier mean deviation progression when applied to real-world-derived early-stage glaucoma data.

PURPOSE: To examine the diagnostic accuracy of performing two (frontloaded) versus one (clinical standard) visual field (VF) test per visit for detecting the progression of early glaucoma in data derived from clinical populations. METHODS: A computer simulation model was used to follow the VFs of 10,000 glaucoma patients (derived from two cohorts: Heijl et al., Swedish cohort; and Chauhan et al., Canadian Glaucoma Study [CGS]) over a 10-year period to identify patients whose mean deviation (MD) progression was detected. Core data (baseline MD and progression rates) were extracted from two studies in clinical cohorts of glaucoma, which were modulated using SITA-Faster variability characteristics from previous work. Additional variables included follow-up intervals (six-monthly or yearly) and rates of perimetric data loss for any reason (0%, 15% and 30%). The main outcome measures were the proportions of progressors detected. RESULTS: When the Swedish cohort was reviewed six-monthly, the frontloaded strategy detected more progressors compared to the non-frontloaded method up to years 8, 9 and 10 of follow-up for 0%, 15% and 30% data loss conditions. The time required to detect 50% of cases was 1.0-1.5 years less for frontloading compared to non-frontloading. At 4 years, frontloading increased detection by 26.7%, 28.7% and 32.4% for 0%, 15% and 30% data loss conditions, respectively. Where both techniques detected progression, frontloading detected progressors earlier compared to the non-frontloaded strategy (78.5%-81.5% and by 1.0-1.3 years when reviewed six-monthly; 81%-82.9% and by 1.2-2.1 years when reviewed yearly). Accordingly, these patients had less severe MD scores (six-monthly review: 0.63-1.67 dB 'saved'; yearly review: 1.10-2.87 dB). The differences increased with higher rates of data loss. Similar tendencies were noted when applied to the CGS cohort. CONCLUSIONS: Frontloaded VFs applied to clinical distributions of MD and progression led to earlier detection of early glaucoma progression.

Interpretation of the Visual Field in Neuro-ophthalmic Disorders.

PURPOSE OF REVIEW: In this review, we will describe current methods for visual field testing in neuro-ophthalmic clinical practice and research, develop terminology that accurately describes patterns of field deficits, and discuss recent advances such as augmented or virtual reality-based perimetry and the use of artificial intelligence in visual field interpretation. RECENT FINDINGS: New testing strategies that reduce testing times, improve patient comfort, and increase sensitivity for detecting small central or paracentral scotomas have been developed for static automated perimetry. Various forms of machine learning-based tools such as archetypal analysis are being tested to quantitatively depict and monitor visual field abnormalities in optic neuropathies. Studies show that the combined use of optical coherence tomography and standard automated perimetry to determine the structure-function relationship improves clinical care in neuro-ophthalmic disorders. Visual field assessment must be performed in all patients with neuro-ophthalmic disorders affecting the afferent visual pathway. Quantitative visual field analysis using standard automated perimetry is critical in initial diagnosis, monitoring disease progression, and guidance of therapeutic plans. Visual field defects can adversely impact activities of daily living such as reading, navigation, and driving and thus impact quality of life. Visual field testing can direct appropriate occupational low vision rehabilitation in affected individuals.

Prediction and Detection of Glaucomatous Visual Field Progression Using Deep Learning on Macular Optical Coherence Tomography.

PRCIS: A deep learning model trained on macular OCT imaging studies detected clinically significant functional glaucoma progression and was also able to predict future progression. OBJECTIVE: To use macular optical coherence tomography (OCT) imaging to predict the future and detect concurrent visual field progression, respectively, using deep learning. DESIGN: A retrospective cohort study. SUBJECTS: A pretraining data set was comprised of 7,702,201 B-scan images from 151,389 macular OCT studies. The progression detection task included 3902 macular OCT imaging studies from 1534 eyes of 828 patients with glaucoma, and the progression prediction task included 1346 macular OCT studies from 1205 eyes of 784. METHODS: A novel deep learning method was developed to detect glaucoma progression and predict future progression using macular OCT, based on self-supervised pretraining of a vision transformer (ViT) model on a large, unlabeled data set of OCT images. Glaucoma progression was defined as a mean deviation (MD) rate of change of ≤ -0.5 dB/year over 5 consecutive Humphrey visual field tests, and rapid progression was defined as MD change ≤ -1 dB/year. MAIN OUTCOME MEASURES: Diagnostic performance of the ViT model for prediction of future visual field progression and detection of concurrent visual field progression using area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. RESULTS: The model distinguished stable eyes from progressing eyes, achieving an AUC of 0.90 (95% CI, 0.88-0.91). Rapid progression was detected with an AUC of 0.92 (95% CI, 0.91-0.93). The model also demonstrated high predictive ability for forecasting future glaucoma progression, with an AUC of 0.85 (95% CI 0.83-0.87). Rapid progression was predicted with an AUC of 0.84 (95% CI 0.81-0.86). CONCLUSIONS: A deep learning model detected clinically significant functional glaucoma progression using macular OCT imaging studies and was also able to predict future progression. Early identification of patients undergoing glaucoma progression or at high risk for future progression may aid in clinical decision-making.

Comparison Between 24-2 ZEST and 24-2 ZEST FAST Strategies in Glaucoma and Ocular Hypertension Using a Fundus Perimeter.

PRCIS: Using a Compass (CMP) (CMP, Centervue, Padova, Italy) fundus perimeter, Zippy Estimation by Sequential Testing (ZEST) FAST strategy showed a significant reduction in examination time compared with ZEST, with good agreement in the quantification of perimetric damage. PURPOSE: The aim of this study was to compare the test duration of ZEST strategy with ZEST FAST and to evaluate the test-retest variability of ZEST FAST strategy on patients with glaucoma and ocular hypertension. PATIENTS AND METHODS: This was a multicenter retrospective study. We analyzed 1 eye of 60 subjects: 30 glaucoma patients and 30 patients with ocular hypertension. For each eye we analyzed, 3 visual field examinations were performed with Compass 24-2 grid: 1 test performed with ZEST strategy and 2 tests performed with ZEST FAST. Mean examination time and mean sensitivity between the 2 strategies were computed. ZEST FAST test-retest variability was examined. RESULTS: In the ocular hypertension cohort, test time was 223±29 seconds with ZEST FAST and 362±48 seconds with ZEST (38% reduction, P <0.001). In glaucoma patients, it was respectively 265±62 and 386±78 seconds (31% reduction using ZEST FAST, P <0.001). The difference in mean sensitivity between the 2 strategies was -0.24±1.30 dB for ocular hypertension and -0.14±1.08 dB for glaucoma. The mean difference in mean sensitivity between the first and the second test with ZEST FAST strategy was 0.2±0.8 dB for patients with ocular hypertension and 0.24±0.96 dB for glaucoma patients. CONCLUSIONS: ZEST FAST thresholding provides similar results to ZEST with a significantly reduced examination time.

Glaucoma Agreement in New Zealand (GAINZ).

CLINICAL RELEVANCE: With an ageing population, ophthalmologists are becoming burdened with glaucoma management, and patient care can be delayed. Therefore, the use of optometrists in glaucoma management can help alleviate the burden. BACKGROUND: The ageing population and subsequent rise of glaucoma prevalence are putting a strain on the public health system in New Zealand. Glaucoma collaborative care between optometrists and ophthalmologists has been gaining support with the aim to reduce this burden on ophthalmologists. There has been little investigation of the agreement in care and management of mild-to-moderate severity glaucoma patients by optometrists and ophthalmologists. METHODS: One hundred and three glaucomatous eyes were used in a survey where clinical history and examination, intraocular pressures (IOPs), visual field testing and optical coherence tomography (OCT) imaging were evaluated for glaucoma progression and decision-making regarding subsequent management by four participants. Two participants were glaucoma-credentialled optometrists (Group 1), and the other two were glaucoma specialists (Group 2). RESULTS: With respect to glaucoma progression, Spearman coefficients identified strong agreement between the two groups for IOP, visual fields and overall status and moderate agreement for OCT imaging. A confusion matrix was used to analyse management and found 80% ± 10% agreement between the two groups. Review periods gave an agreement of 55% ± 20% between the two groups. CONCLUSION: There was strong agreement in the assessment of glaucoma progression between the two groups. The 80% level of agreement for subsequent management between the two groups is comparable to other published reports. These results provide some reassurance that a collaborative care system can perform safely and as intended.

Visual Sensitivity Loss in Geographic Atrophy: Structure-Function Evaluation Using Defect-Mapping Microperimetry.

Purpose: To examine the structure-function relationship in eyes with geographic atrophy (GA) using defect-mapping microperimetry, a testing strategy optimized to quantify the spatial extent of deep visual sensitivity losses. Methods: Fifty participants with GA underwent defect-mapping microperimetry testing of the central 8°-radius region (208 locations tested once with a 10-decibel stimuli) and fundus autofluorescence imaging in one eye. The GA extent in the corresponding central 8°-radius was derived by manual annotations and image co-registration to examine the global structure-function relationship. The distance of each test location from the GA margin was also derived, and regions defined, to examine the local structure-function relationship. Results: GA extent in the central 8° explained a substantial proportion of variance in the percentage of locations missed (nonresponse) on microperimetry at the global level (R2 = 0.90). At a local level, the probability of missing stimuli at the outer junctional zone (0-500 µm outside the GA margin) and GA margin (probability = 7% and 34%, respectively) was higher than at the outer nonlesional zone (>500 µm outside the GA margin; probability = 2%; P < 0.001 for both). The probability of missing stimuli at the inner junctional zone (0-250 µm inside the GA margin) was also lower than at the inner lesional zone (>250 µm inside the GA margin; probability = 64% and 88%; P < 0.001). Conclusions: This study confirms the expected functional relevance of the region with GA on fundus autofluorescence imaging and underscores the potential effectiveness of defect-mapping microperimetry testing for capturing visual function changes when evaluating new GA treatments.

Objective detection of visual field defects with multifrequency VEPs.

PURPOSE: To correlate multifrequency pattern reversal VEPs in quadrants (QmfrVEPs) with perimetric field losses for objective detection of visual field losses. METHODS: QmfrVEP measurements were performed using four LED-based checkerboard stimulators to stimulate the four quadrants of the visual field. QmfrVEPs were measured monocularly in 5 normal subjects and in 5 glaucoma patients who showed losses in conventional Octopus perimetry. The pattern reversal frequency varied slightly between the stimulators: (11.92, 12.00, 12.08 and 12.16 reversals/sec). The responses to the different stimuli were identified by discrete Fourier analysis. VEPs were recorded using different electrode configurations, and the recording with the highest signal-to-noise ratio (SNR) was used for further analysis. RESULTS: QmfrVEP responses from the different quadrants can be reliably measured and separated using the 0.08 reversals/sec interstimulus reversal frequency differences. The signal-to-noise ratio in the four quadrants was significantly correlated with the equivalent visual field losses obtained with perimetry (Spearman rank correlation: P < 0.001). In the five glaucoma patients, the SNR was reduced in 15 out of the 16 quadrants with a perimetric defect, in comparison to the results in quadrants of healthy subjects. This confirms the sensitivity of the procedure. CONCLUSION: QmfrVEP responses can be measured reliably. This pilot study suggests that high SNR values exclude visual field defects and that focal defects can be identified in glaucoma patients. TRIAL REGISTRATION: www. CLINICALTRIALS: gov . NCT00494923.

Detection and characterisation of visual field defects using Octopus perimetry in congenital glaucoma.

PURPOSE: To detect and characterise visual field (VF) defects using static Octopus perimetry in patients with primary congenital glaucoma (PCG) and to determine VF quality and time duration. MATERIAL AND METHODS: Eighty-eight eyes of 70 patients diagnosed with PCG were included. Assessments were performed using an Octopus 900 and each eye was assessed with the tendency-oriented perimetry (G-TOP) algorithm. Quantitative VF data were collected: quality data (false positive and negative response, and time duration) and results of mean deviation (MD) and square root of loss variance (sLV). Qualitative data were collected: the presence of diffuse and localized defects, the affected hemifield and grade of defects using the Aulhorn and Karmeyer classification. Correlations between perimetric results and clinical variables were analysed. RESULTS: Median age was 11 (8-17) years. 65.9% (58/88) of PCG eyes showed VF defects. Diffuse defects were observed in 10/58 eyes (16.94%) (mean MD = 23.92 [SD: 2.52]) dB) and localized defects in 48/58 eyes (82.75%). The most frequent defect was spot-like/stroke-like/incipient paracentral scotoma (n = 15), nasal step (n = 8), adding arcuate defect (n = 2), half ring-shaped (n = 13) and concentric defect with a central island (n = 9). And the most frequent affected visual hemifield was inferior hemifield. Mean test duration was 2 min 12 s (SD: 21.6 s). MD and sLV values were correlated with best corrected visual acuity (BCVA), cup to disc ratio and number of antiglaucoma surgeries (all P < .001). CONCLUSION: A high number of diffuse and localized defects were identified using Octopus perimetry in PCG patients. The most frequent defect was paracentral scotoma and inferior hemifield was the most affected.

An Extensive-Form Game Paradigm for Visual Field Testing via Deep Reinforcement Learning.

Glaucoma is the leading cause of irreversible but preventable blindness worldwide, and visual field testing is an important tool for its diagnosis and monitoring. Testing using standard visual field thresholding procedures is time-consuming, and prolonged test duration leads to patient fatigue and decreased test reliability. Different visual field testing algorithms have been developed to shorten testing time while maintaining accuracy. However, the performance of these algorithms depends heavily on prior knowledge and manually crafted rules that determine the intensity of each light stimulus as well as the termination criteria, which is suboptimal. We leverage deep reinforcement learning to find improved decision strategies for visual field testing. In our proposed algorithms, multiple intelligent agents are employed to interact with the patient in an extensive-form game fashion, with each agent controlling the test on one of the testing locations in the patient's visual field. Through training, each agent learns an optimized policy that determines the intensities of light stimuli and the termination criteria, which minimizes the error in sensitivity estimation and test duration at the same time. In simulation experiments, we compare the performance of our algorithms against baseline visual field testing algorithms and show that our algorithms achieve a better trade-off between estimation accuracy and test duration. By retaining testing accuracy with reduced test duration, our algorithms improve test reliability, clinic efficiency, and patient satisfaction, and translationally affect clinical outcomes.