Categorizing the stage of glaucoma from pre-diagnosis to end-stage disease

Accuracy of Bruch's membrane opening minimum rim width and retinal nerve fiber layer thickness in glaucoma diagnosis depending on optic disc size

BACKGROUND/AIM

The aim of this paper is to compare retinal nerve fiber layer thickness (RNFL) and Bruch's membrane opening-based minimum rim width (BMO-MRW) in terms of their performance in detecting early and moderate/advanced glaucoma using receiver operating characteristics (ROC) analysis and the classification using the 5th percentile as a cut-off.

METHODS

One hundred eyes from 100 patients with early glaucoma (mean deviation (MD): < -5.0 dB) and 100 eyes from 100 patients with moderate/advanced glaucoma (MD: > -5.0 dB) were carefully matched to healthy controls based on optic disc size. Then, the dataset was divided, based on the 50th percentile of the measured Bruch's membrane opening area (BMO-A), into small (BMO-A < 1.95 mm2) and large optic discs (BMO-A > 1.95 mm2). Finally, the discriminative performance of BMO-MRW and RNFL between glaucoma and controls using ROC analysis and the manufacturer's classification based on the 5th percentile was analyzed.

RESULTS

In discriminating between glaucoma and matched healthy controls, global BMO-MRW and global RNFL thickness had comparable areas under the ROC curve for eyes with early glaucoma and both small BMO-As (ROC ± confidence interval [CI] 0.91 [0.87 to 0.95] and 0.88 [0.83 to 0.93]) and large BMO-As (0.86 [0.82 to 0.92] and 0.84 [0.79 to 0.90]), as well as in moderate/advanced glaucoma with small BMO-As (0.99 [0.98 to 1.00] and 0.97 [0.95 to 1.00]) and large BMO-As (0.94 [0.91 to 0.98] and 0.97 [0.94 to 1.00]). Using the calculated 5th percentile as a threshold value, the sensitivities for the detection of early and moderate/advanced glaucoma were comparable for BMO-MRW and RNFL in eyes with small optic discs (early glaucoma: fifty-two percent and 61%; moderate/advanced glaucoma: ninety-one percent and 92%). In eyes with large optic discs, the sensitivity of BMO-MRW was inferior to that of RNFL for both early (38% versus 51%) and moderate/advanced (80% versus 91%) glaucoma.

CONCLUSION

Based on an ROC analysis, the discriminative performance of BMO-MRW and RNFL between patients with early and moderate/advanced glaucoma and a healthy control group matched based on optic disc size is comparable in eyes with BMO-As smaller and larger 1.95 mm2. Using a classification based on the 5th percentile, as used in clinical practice, RNFL is shown to be superior to BMO-MRW regarding sensitivity in glaucoma detection with large optic discs. This study underscores the importance of RNFL imaging and measurement in the diagnostic evaluation of glaucoma, especially in cases of large optic discs.

Ab interno canaloplasty versus gonioscopy-assisted transluminal trabeculotomy in open-angle glaucoma: a randomised controlled trial

OBJECTIVE

To compare the efficacy and safety of ab interno canaloplasty (ABiC) with gonioscopy-assisted transluminal trabeculotomy (GATT) in patients with open-angle glaucoma (OAG).

METHOD

This randomised clinical trial recruited eyes with OAG and no previous incisional ocular surgery, among which 38 were randomised to ABiC and 39 to GATT. Follow-ups were performed at 1, 3, 6 and 12 months postoperatively. The primary outcome measures were intraocular pressure (IOP) and use of glaucoma medication at 12 months postoperatively. The secondary outcome measure was complete surgical success (not requiring glaucoma surgery, IOP ≤21 mm Hg and non-use of glaucoma medications).

RESULTS

Both groups had similar demographic and ocular characteristics. A total of 71 of the 77 subjects (92.2%) completed 12-month follow-up. At 12 months, mean IOP was 19.0±5.2 mm Hg in the ABiC group and 16.0±3.1 mm Hg in the GATT group (p=0.003). Overall, 57.2% of ABiC patients and 77.8% of GATT patients were medication free (p=0.06). The number of glaucoma medications was 0.9±1.3 in the ABiC group and 0.6±1.2 in the GATT group (p=0.27). The 12-month cumulative rate of complete surgical success was 56% in the ABiC group and 75% in the GATT group (p=0.09). Three eyes in the ABiC group and one eye in the GATT group required additional glaucoma surgery. Hyphema (87% vs 47%) and supraciliary effusion (92% vs 71%) were noted more often in the GATT group than in the ABiC group.

CONCLUSIONS

The preliminary result showed that GATT had an advantage over ABiC in IOP reduction for OAG patients, accompanied by favourable safety at 12-month postoperatively.

TRIAL REGISTRATION NUMBER

ChiCTR1800016933.

Optical coherence tomography choroidal enhancement using generative deep learning

Spectral-domain optical coherence tomography (SDOCT) is the gold standard of imaging the eye in clinics. Penetration depth with such devices is, however, limited and visualization of the choroid, which is essential for diagnosing chorioretinal disease, remains limited. Whereas swept-source OCT (SSOCT) devices allow for visualization of the choroid these instruments are expensive and availability in praxis is limited. We present an artificial intelligence (AI)-based solution to enhance the visualization of the choroid in OCT scans and allow for quantitative measurements of choroidal metrics using generative deep learning (DL). Synthetically enhanced SDOCT B-scans with improved choroidal visibility were generated, leveraging matching images to learn deep anatomical features during the training. Using a single-center tertiary eye care institution cohort comprising a total of 362 SDOCT-SSOCT paired subjects, we trained our model with 150,784 images from 410 healthy, 192 glaucoma, and 133 diabetic retinopathy eyes. An independent external test dataset of 37,376 images from 146 eyes was deployed to assess the authenticity and quality of the synthetically enhanced SDOCT images. Experts' ability to differentiate real versus synthetic images was poor (47.5% accuracy). Measurements of choroidal thickness, area, volume, and vascularity index, from the reference SSOCT and synthetically enhanced SDOCT, showed high Pearson's correlations of 0.97 [95% CI: 0.96-0.98], 0.97 [0.95-0.98], 0.95 [0.92-0.98], and 0.87 [0.83-0.91], with intra-class correlation values of 0.99 [0.98-0.99], 0.98 [0.98-0.99], and 0.95 [0.96-0.98], 0.93 [0.91-0.95], respectively. Thus, our DL generative model successfully generated realistic enhanced SDOCT data that is indistinguishable from SSOCT images providing improved visualization of the choroid. This technology enabled accurate measurements of choroidal metrics previously limited by the imaging depth constraints of SDOCT. The findings open new possibilities for utilizing affordable SDOCT devices in studying the choroid in both healthy and pathological conditions.

Disability-Adjusted Life Years Resulting from Ocular Injury among Deployed Service Members, 2001-2020

PURPOSE

To quantify the burden of ocular injuries on deployed US service members by calculating disability-adjusted life years (DALYs).

DESIGN

Retrospective, observational cohort study.

PARTICIPANTS

US service members with ocular injuries sustained in combat zones from January 1, 2001 to May 19, 2020.

METHODS

Health states and duration of injuries were identified using data from the Defense and Veterans Eye Injury and Vision Registry. These health states were mapped to disability weights from the Global Burden of Disease (GBD) study. Average duration of injury or illness was calculated until remission or death. For the latter, life expectancy at age of sustaining injury, as identified from US Life Tables from the National Vital Statistics Reports 2020, was used. Using Defense Manpower Data Center reports capturing number of service members deployed per year, incidence rates were calculated for ocular injury and DALYs.

MAIN OUTCOME MEASURES

Disability-adjusted life years of ocular injury.

RESULTS

Seventeen thousand five hundred fifty-five patients sustained ocular injury that incurred DALYs. In total, these injuries resulted in 11 214 DALYs (average, 0.64 DALYs per included patient and 20.6 DALYs per 10 000 US service members per year). Severe impairment of distance vision (77.9%) and blindness (10.6%) were the primary contributors of DALYs. Although only 9.3% of patients sustained a permanent ocular injury, permanent disability accounted for 99.5% of total DALYs. The average yearly incidence rate of ocular injury was 32.0 cases per 10 000 US service members. Foreign body was the most frequent injury type (2754 occurrences), followed by abrasion (2419 occurrences) and multiple injury types (1429 occurrences). The most DALYs occurred in patients with multiple injury types (2485 DALYs), followed by abrasion (accounting for 725 DALYs) and foreign body (accounting for 461 DALYs).

DISCUSSION

We report higher average DALYs per case ratio among US service members compared with the general population studied by the GBD study, highlighting the differences in probabilities of permanent injury between the two studies. Our study provides understanding of the impact of ocular injuries on active-duty service members and lays the groundwork for further research and interventions to mitigate their burden.

FINANCIAL DISCLOSURE(S)

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

Effect of Preoperative Trabecular Meshwork Pigmentation and Other Eye Characteristics on Outcomes of Combined Phacoemulsification/Minimally Invasive Glaucoma Surgery

PURPOSE

To investigate associations between pigmentation of the trabecular meshwork (PTM) and other preoperative eye characteristics and outcomes of minimally invasive glaucoma surgery combined with phacoemulsification (Phaco/MIGS).

DESIGN

Retrospective interventional case series.

PARTICIPANTS

Academic glaucoma clinic patients with symptomatic cataract and glaucoma treated with combined Phaco/MIGS.

METHODS

Analyzing preoperative PTM, intraocular pressure (IOP), IOP-lowering medications and visual acuity (VA) data in relation to Phaco/MIGS outcomes.

MAIN OUTCOME MEASURES

Pigmentation of the trabecular meshwork and other preoperative eye characteristics in relation to Phaco/MIGS success defined as postoperative IOP between 5 and 21 mmHg and IOP reduction of ≥ 20% and/or a reduction of ≥ 1 IOP-medications compared to baseline, and final IOP, IOP-lowering medications and VA.

RESULTS

A total of 265 eyes (172 patients, mean age, 73.5 [standard deviation, 10.0], range 35-95 years, male 40.0%) were identified and categorized with high PTM (108 eyes, 40.8%) or low PTM (157 eyes, 59.2%). The high PTM group, compared with the low PTM group, demonstrated higher preoperative IOP (16.7 [standard error 0.4] vs. 15.2 [0.4] mmHg, P = 0.009), included more eyes with primary open-angle glaucoma (POAG, P = 0.03), fewer eyes with normal-tension glaucoma (NTG, P = 0.01), and fewer eyes with mild stage glaucoma (P = 0.001). Compared to baseline, final IOP decreased by 6.5 [2.4]% and 13.4 [3.0]% (P = 0.075) to 13.5 [0.3] mmHg and 13.6 [0.4] mmHg (P = 0.77) in the low and high PTM groups, respectively, and IOP-lowering medications decreased by 34.6 [4.9]% (n = 116) and 18.1 [7.3]% (n = 85), respectively (P = 0.062). Surgical success was 59.9% and 58.3%, respectively (P = 0.87). It was positively associated with higher preoperative IOP (hazard ratio 1.08 [95% confidence interval 1.04-1.12] P < 0.0001) and higher number of preoperative IOP-medications (1.20 [1.05-1.37] P = 0.007), negatively associated with history of selective laser trabeculoplasty (SLT, 0.40 [0.23-0.68] P = 0.0009) and longer axial length (0.87 [0.80-0.94], P = 0.0006), but was not associated with PTM.

CONCLUSIONS

Higher PTM was associated with POAG rather than NTG, with more severe glaucoma and higher preoperative IOP, but not with Phaco/MIGS success. Surgical success was positively associated with higher preoperative IOP and number of IOP-medications and negatively associated with history of SLT and longer axial length. These findings may help guide glaucoma surgeons in surgical planning and patient counseling.

FINANCIAL DISCLOSURE(S)

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

Extraction of three-dimensional shapes in glaucoma patients in response to monocular depth cues

PURPOSE

To assess the impact of glaucoma on perceiving three-dimensional (3D) shapes based on monocular depth cues.

STUDY DESIGN

Clinical observational study.

METHODS

Twenty glaucoma patients, subjected to binocular visual-field sensitivity (binocular-VFS) tests using a Humphrey Visual Field Analyzer, and 20 age-matched healthy volunteers, underwent two tasks: identifying the nearest vertex of a 3D shape using monocular shading (3D-SfS), texture (3D-SfT), or motion (3D-SfM) cues, and distinguishing elementary one-dimensional (1D) features of these cues. The association of the visual-field index (VFI) of binocular-VFS with 3D shape perception in glaucoma patients was also examined.

RESULTS

Glaucoma patients demonstrated reduced accuracy in distinguishing 1D luminance brightness and a larger "error-in-depth" between the perceived and actual depths for 3D-SfM and 3D-SfS compared to healthy volunteers. Six glaucoma patients with a 100% VFI for binocular-VFS exhibited a similar error-in-depth to the other fourteen glaucoma patients; they had a larger error-in-depth for 3D-SfM compared to healthy volunteers. No correlation between the error-in-depth values and the VFI values of binocular-VFS was observed.

CONCLUSIONS

The 3D shape perception in glaucoma patients varies based on the depth cue's characteristics. Impaired 1D discrimination and larger thresholds for 3D-SfM in glaucoma patients with a 100% VFI for binocular-VFS indicate more pronounced perceptual deficits of lower-level elementary features for 3D-SfS and higher-level visual processing of 3D shapes for 3D-SfM. The effects of the location and degree of binocular visual-field defects on 3D shape perception remain to be elucidated. Our research provides insights into the 3D shape extraction mechanism in glaucoma.

Retinal Nerve Fiber Layer Damage Assessment in Glaucomatous Eyes Using Retinal Retardance Measured by Polarization-Sensitive Optical Coherence Tomography

Purpose

To assess the diagnostic performance and structure-function association of retinal retardance (RR), a customized metric measured by a prototype polarization-sensitive optical coherence tomography (PS-OCT), across various stages of glaucoma.

Methods

This cross-sectional pilot study analyzed 170 eyes from 49 healthy individuals and 68 patients with glaucoma. The patients underwent PS-OCT imaging and conventional spectral-domain optical coherence tomography (SD-OCT), as well as visual field (VF) tests. Parameters including RR and retinal nerve fiber layer thickness (RNFLT) were extracted from identical circumpapillary regions of the fundus. Glaucomatous eyes were categorized into early, moderate, or severe stages based on VF mean deviation (MD). The diagnostic performance of RR and RNFLT in discriminating glaucoma from controls was assessed using receiver operating characteristic (ROC) curves. Correlations among VF-MD, RR, and RNFLT were evaluated and compared within different groups of disease severity.

Results

The diagnostic performance of both RR and RNFLT was comparable for glaucoma detection (RR AUC = 0.98, RNFLT AUC = 0.97; P = 0.553). RR showed better structure-function association with VF-MD than RNFLT (RR VF-MD = 0.68, RNFLT VF-MD = 0.58; z = 1.99; P = 0.047) in glaucoma cases, especially in severe glaucoma, where the correlation between VF-MD and RR (r = 0.73) was significantly stronger than with RNFLT (r = 0.43, z = 1.96, P = 0.050). In eyes with early and moderate glaucoma, the structure-function association was similar when using RNFLT and RR.

Conclusions

RR and RNFLT have similar performance in glaucoma diagnosis. However, in patients with glaucoma especially severe glaucoma, RR showed a stronger correlation with VF test results. Further research is needed to validate RR as an indicator for severe glaucoma evaluation and to explore the benefits of using PS-OCT in clinical practice.

Translational Relevance

We demonstrated that PS-OCT has the potential to evaluate the status of RNFL structural damage in eyes with severe glaucoma, which is currently challenging in clinics.

Measuring Visual Fields in Children With Glaucoma Using a Portable Tablet

Purpose

To compare perimetric outcomes of an iPad perimetry app (Melbourne Rapid Fields [MRF]) with those of the Humphrey Field Analyser (HFA) testing children with glaucoma.

Methods

Sixteen children diagnosed and treated for glaucoma were recruited to evaluate their perimetric performance over two visits. At each visit, they undertook visual field assessment using the MRF application as well as the HFA. The HFA test was part of their usual clinical work up and a clinical assistant judged which test format (24-2 SITA standard or SITA fast) might be suited to the testing of that child. The primary outcome measure was the association and repeatability of mean deviation (MD) for the MRF and HFA tests, by way of regression, intraclass correlation coefficient and Bland-Altman analysis. Secondary measures were comparisons of pattern deviation indices, test times as well as an indication of participant test preference. Summary data show means ± standard deviation.

Results

The age for our cohort was 7 to 15 years of age (mean, 10.0 ± 2.4 years of age). The MRF MD was in close concordance to HFA MD with an intraclass correlation coefficient of 0.91 (95% confidence interval, 0.82-0.95). Bland-Altman analysis found little bias (-0.6 dB) and a 95% coefficient of repeatability of 2.1 dB in eyes having a normal HFA MD. In eyes with glaucomatous visual field defects the 95% coefficient of repeatability at retest was much larger for both the MRF (10.5 dB) as well as for the HFA (10.0 dB). Average MRF test times (5.6 ± 1.2 minutes) were similar to SITA Fast (5.4 ± 1.9 minutes) with both being significantly faster than SITA standard (8.6 ± 1.4 minutes; P < 0.001). All children chose testing with the MRF as their preference.

Conclusions

MRF correlated strongly with HFA and was preferred by the children over the HFA. MRF is suitable for perimetric evaluation of children with glaucoma.

Translational Relevance

This study finds that an iPad based visual field test can be used with children having glaucoma to yield outcomes similar to SITA-fast. Children indicate a preference for such testing.

Study of the ganglion cell complex of the macula by optical coherence tomography in the diagnosis of glaucoma progression

INTRODUCTION

The aim of this work is to evaluate the usefulness of the study of the ganglion cell complex of the macula using the OCT technique to estimate the progression of glaucoma according to its severity.

MATERIAL AND METHODS

This is a retrospective cross-sectional study. It includes 205 eyes of 131 patients with glaucoma or ocular hypertension followed for a mean of 5.7 years. The parameters and rates of three tests have been analyzed using the progression software of each instrument: visual field, optical coherence tomography (OCT) in the ganglion cell complex of the macula and in the nerve fiber layer of the optic nerve. The results of each test, the concordance between them and how they differ according to severity stage have been evaluated.

RESULTS

Visual field classifies more cases of progression in moderate-advanced glaucoma, while in mild glaucoma its capacity is limited. Optic nerve fiber layer OCT classifies more cases of progression in mild glaucoma than in moderate-advanced glaucoma, as it is artifacted by the floor effect. OCT of the macular ganglion cell complex is the test that classifies more cases of progression and has the highest agreement with visual field, regardless of severity.

CONCLUSION

In both mild and moderate-advanced glaucoma, OCT of the macula ganglion cell complex may be a better biomarker of progression than OCT of the macula ganglion cell complex.

An Artificial Intelligence Enabled System for Retinal Nerve Fiber Layer Thickness Damage Severity Staging

Purpose

To develop an objective glaucoma damage severity classification system based on OCT-derived retinal nerve fiber layer (RNFL) thickness measurements.

Design

Algorithm development for RNFL damage severity classification based on multicenter OCT data.

Subjects and Participants

A total of 6561 circumpapillary RNFL profiles from 2269 eyes of 1171 subjects to develop models, and 2505 RNFL profiles from 1099 eyes of 900 subjects to validate models.

Methods

We developed an unsupervised k-means model to identify clusters of eyes with similar RNFL thickness profiles. We annotated the clusters based on their respective global RNFL thickness. We computed the optimal global RNFL thickness thresholds that discriminated different severity levels based on Bayes' minimum error principle. We validated the proposed pipeline based on an independent validation dataset with 2505 RNFL profiles from 1099 eyes of 900 subjects.

Main Outcome Measures

Accuracy, area under the receiver operating characteristic curve, and confusion matrix.

Results

The k-means clustering discovered 4 clusters with 1382, 1613, 1727, and 1839 samples with mean (standard deviation) global RNFL thickness of 58.3 (8.9) μm, 78.9 (6.7) μm, 87.7 (8.2) μm, and 101.5 (7.9) μm. The Bayes' minimum error classifier identified optimal global RNFL values of > 95 μ m , 86 to 95 μ m , 70 to 85 μ m , and < 70 μ m for discriminating normal eyes and eyes at the early, moderate, and advanced stages of RNFL thickness loss, respectively. About 4% of normal eyes and 98% of eyes with advanced RNFL loss had either global, or ≥ 1 quadrant, RNFL thickness outside of normal limits provided by the OCT instrument.

Conclusions

Unsupervised machine learning discovered that the optimal RNFL thresholds for separating normal eyes and eyes with early, moderate, and advanced RNFL loss were 95 μ m , 85 μm, and 70 μ m , respectively. This RNFL loss classification system is unbiased as there was no preassumption or human expert intervention in the development process. Additionally, it is objective, easy to use, and consistent, which may augment glaucoma research and day-to-day clinical practice.

Financial Disclosures

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

Comparison of disease severity in glaucoma patients identified by screening in the 1990s and in routine clinical care in the 2010s in Sweden

BACKGROUND AND PURPOSE

In a previous study comparing the amount of visual field damage at presentation in patients having open-angle glaucoma (OAG) identified through screening and in patients diagnosed in routine clinical practice in the 1990s, the damage was considerably worse in the clinically diagnosed patients. In the present study we compare visual field damage at presentation in the same 402 screened patients with that seen in 281 newly detected previously untreated patients clinically diagnosed in the 2010s.

METHODS

The perimetric visual field index mean deviation (MD) was compared in the two groups of patients.

RESULTS

In the clinical patients diagnosed with bilateral visual field damage the median MD was -5.1 dB in the better eye and -13.0 dB in the worse eye. In the screened patients the median MD in the better eye was -6.5 dB and -11.5 dB in the worse eye. The differences between the clinical and screened patients were non-significant, p = 0.28 and p = 0.67 respectively. More clinical patients had severe visual field loss, defined as MD less than -20 dB, in the worse eye than in the screened patients, 18.5% versus 12.7% respectively, p = 0.037.

CONCLUSION

The visual field damage at presentation in clinically diagnosed OAG patients has improved in the past 20 years, but the proportion of patients with severe visual field loss in at least one eye, almost 20%, is still unacceptably high considering that severe visual field damage at presentation is the most important risk factor for later development of glaucoma blindness.

Intraocular pressure spikes after gonioscopy-assisted transluminal trabeculotomy (GATT)

PURPOSE

Intraocular pressure (IOP) spikes (IOP > 30 mmHg or > 10 mmHg above baseline IOP) are a common and worrisome complication of gonioscopy-assisted transluminal trabeculotomy (GATT). The purpose of this study is to identify risk factors for IOP spikes and to describe their characteristics, management, and clinical course in a large cohort of patients.

METHODS

A retrospective, single-center study which included 217 consecutive eyes of patients that underwent GATT between December 2019 and April 2022 with follow-up of at least 90 days.

RESULTS

IOP spikes occurred in 52 of 217 (24%) eyes. Spikes occurred in 15.5% of patients in whom pre-operative IOP-lowering medications were continued after surgery (90 eyes), and in 29.9% in whom IOP-lowering medications were stopped after surgery (127 eyes). Spikes were diagnosed at a mean of 7.7 ± 6.5 days after surgery. All IOP spikes occurred within the first month of surgery. The mean duration of a spike was 4.9 ± 5.4 days. Management of IOP spikes included adding a mean of 3.13 ± 1.7 groups of glaucoma medications. Thirty-seven (72.5%) eyes were treated with oral carbonic anhydrase inhibitor, 11 (21.6%) were treated with IV mannitol, and anterior chamber paracentesis was performed in 16 (31.4%). Six (11.8%) eyes underwent additional glaucoma surgery to control IOP. Patients that continued their pre-operative IOP-lowering medications after surgery were 2.3 times less likely to develop a spike as compared to patients who discontinued their medications (P = 0.016). Spikes were found to be a risk factor for failure of GATT.

CONCLUSIONS

IOP spikes are a common occurrence after GATT. They most commonly appear during the first two post-operative weeks and usually resolve with topical and systemic IOP-lowering treatment. The continuation of IOP-lowering medications after GATT is recommended to lower the risk of IOP spikes.

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.

Long-term functional and structural outcomes in patients with primary congenital glaucoma-A Danish nationwide study

PURPOSE

Evaluation of long-term functional and structural outcomes in patients with primary congenital glaucoma (PCG) based on visual acuity (VA), visual field (VF) using standard automated perimetry, and peripapillary retinal nerve fibre layer thickness (pRNFL).

METHODS

We retrospectively reviewed medical records of all patients diagnosed with PCG in Denmark from 1977 to 2016. Severe vision loss was defined as VA <6/60 and/or VF >20 decibels (dB). Prognostic factors were evaluated in a correlation matrix.

RESULTS

The median age of the 94 patients (153 PCG eyes) was 12 years (IQR 9-16). In PCG eyes 62% had VA ≥6/18 but 22% had <6/60. VA in the better seeing eye was ≥6/18 in 90% and <6/60 in 5%. VF was measured in 59 PCG eyes and the median mean defect was 5.1 dB (IQR 2.1-9.6) with 52% better than 6 dB and 9% worse than 20 dB. Generalized pRNFL was reduced below the age-expected 1st percentile in 29% of the 58 PCG eyes where pRNFL was measured. Poor VA, poor VF and reduced pRNFL were all correlated (p = 0.0001). More surgeries (p < 0.0001) and longer diagnostic delay (p = 0.004) were associated with poorer vision and to a lesser degree with poor VF pRNFL.

CONCLUSION

In Denmark, most patients with bilateral PCG retain VA ≥6/18 in the better seeing eye. Poor VA was associated with poor VF. Longer diagnostic delay and more surgeries were associated with a poorer prognosis.

Genetic risk of glaucoma is associated with vascular and retinal nerve fibre wedge defects

PURPOSE

To evaluate the association between localised vascular and retinal nerve fibre layer (RNFL) loss and genetic risk for glaucoma and cardiovascular disease using polygenic risk scores (PRS).

METHODS

858 eyes were included from 455 individuals with suspect and early manifest primary open angle glaucoma. Eyes were characterised as having localised vascular and/or RNFL wedge-shaped defects by scrutiny of optical coherence tomography angiography (OCTA) and OCT images, respectively. Investigations included associations with pre-established scores for genetic risk of glaucoma and cardiovascular disease in the context of glaucoma risk factors and systemic vascular disease outcomes.

RESULTS

Higher genetic risk for glaucoma was associated with both vascular wedge defects and RNFL defects (p < 0.001 and p = 0.020, respectively). A greater genetic risk of glaucoma was associated with the presence of multiple vascular wedges per eye (p = 0.005). Glaucoma progression based on global RNFL loss was associated with vascular and RNFL wedge defects (p ≤ 0.001 and p = 0.008, respectively). The glaucoma PRS was significantly associated with vascular, but not RNFL, wedge defects after controlling for disc haemorrhage (p = 0.007 and p = 0.070, respectively). Vascular wedge defects were not related to the cardiovascular PRS.

CONCLUSION

Individuals with a higher genetic risk of glaucoma based on the PRS were more likely to have retinal vascular defects, as well as structural glaucomatous loss, but this did not relate to systemic cardiovascular risk. This possibly implies a local pathophysiology for the vascular defects in some cases, which may have clinical relevance in the early stages of glaucoma and in individuals at high genetic risk.

Performance of perimetric glaucoma staging systems and their preference patterns among the Indian eye care practitioners

CONTEXT

Various systems are available to stage glaucomatous field defects into different severity grades. Still, the preference for such systems among Indian eye care practitioners (ECPs) and the consensus between them are not explored.

PURPOSE

To compare the clinical performance of perimetric glaucoma staging systems and to assess their preference patterns among Indian ECPs.

SETTING AND DESIGN

Retro-prospective cross-sectional study.

METHODS

Three investigators stratified 400 perimetry reports using four systems: Hodapp Anderson Parrish (HAP), enhanced Glaucoma Severity Staging (eGSS), Advanced Glaucoma Intervention Study (AGIS), and Collaborative Initial Glaucoma Treatment Study (CIGTS). Their performance was compared in terms of agreement and association. Following this, 30 ECPs from across the country segregated a subset of reports (n = 20) into different stages based on their system of choice, and their preferences/perceptions about the available perimetry staging systems were enquired and documented.

STATISTICAL ANALYSIS USED

Descriptive statistics, Kruskal-Wallis, Cohen's kappa, and Spearman's correlation.

RESULTS

For the consolidated severity stages, substantial agreements (K ranging from 0.61 to 0.75) were found between all the systems, except for HAP-CIGTS (K = 0.58) and AGIS-CIGTS (K = 0.51). All ECPs were aware of perimetry staging systems, and a high preference was reported for HAP (97%) due to ease of implementation and interpretation.

CONCLUSION

Among the four staging systems, the highest agreement was found between HAP and eGSS. A majority of ECPs proposed the need for a uniform classification system across the practices for clinical comparisons and patient education.

Differentiating stages of functional vision loss from glaucoma using the Disc Damage Likelihood Scale and cup:disc ratio

BACKGROUND

Glaucoma staging is critical for treatment planning but has rarely been tested in severe/end-stage disease. We compared the performance of the Disc Damage Likelihood Scale (DDLS) and cup:disc ratio (CDR) using a functional glaucoma staging system (GSS) as the reference standard.

METHODS

Post hoc analysis of a randomised controlled trial at the Eye Department of Kilimanjaro Christian Medical Centre, Tanzania. Eligible participants (aged ≥18 years) with open-angle glaucoma, intraocular pressure (IOP) of >21 mm Hg, were randomised to timolol 0.5% eye drops or selective laser trabeculoplasty. Fundoscopy established vertical and horizontal CDRs and DDLS. Visual acuity and static visual fields were graded (GSS). The study used area under the receiver operating characteristic (AROC) curves and Spearman's rank correlation coefficients to compare staging systems. Logistic regression with generalised estimating equations determined risk factors of functional severe/end-stage glaucoma.

RESULTS

382 eyes (201 participants) were evaluated; 195 (51%) had severe or end-stage glaucoma; mean IOP was 26.7 (SD 6.9) mm Hg. DDLS yielded an AROC of 0.90 (95% CI 0.87 to 0.93), vertical cup:disc ratio (vCDR) of 0.88 (95% CI 0.85 to 0.91, p=0.048) for identifying severe/end-stage disease. Correlation coefficients comparing GSS to DDLS and vCDRs were 0.73 and 0.71, respectively. Advanced structural stages, vision impairment, higher IOP and less financial resources were risk factors of functional severe/end-stage glaucoma.

CONCLUSION

This study indicates that both structural staging systems can differentiate severe/end-stage glaucoma from less severe disease, with a moderate advantage of DDLS over CDR. Clinical examination of the optic disc plays an important role in addition to functional assessment when managing severe/end-stage glaucoma.

Steroids and/or Non-Steroidal Anti-Inflammatory Drugs as Postoperative Treatment after Trabeculectomy-12-Month Results of a Randomized Controlled Trial

This prospective randomized controlled trial aimed to compare the efficacy and safety of topical preservative-free diclofenac (DICLO) to dexamethasone (DEX) eyedrops, and their combination (DEX+DICLO) after trabeculectomy. Sixty-nine patients with medically uncontrolled glaucoma were randomized to receive topical postoperative treatment with DICLO (n = 23), DEX (n = 23), or a combination of DEX and DICLO (n = 23). The primary outcome was the intraocular pressure (IOP) 12 months postoperatively. Secondary outcomes included surgical success, failure, visual field, and visual acuity from baseline to 12 months postoperatively. IOP reached the lowest point one day after trabeculectomy. At 12 months, IOP was 10.0 mmHg (95% CI, 8.4-11.6 mmHg) for DICLO, 10.9 mmHg (95% CI, 9.4-12.3 mmHg) for DEX, and 11.2 mmHg (95% CI, 9.1-13.3 mmHg) for DEX+DICLO. There were no significant differences in IOP, surgical success, failure, visual field, or visual acuity between the DICLO, DEX, or DEX+DICLO groups. We found that topical diclofenac was not statistically different from topical dexamethasone in controlling IOP 12 months after trabeculectomy. Combining diclofenac and dexamethasone offered no added IOP control compared to dexamethasone alone.

The impact of visual function on staircase use performance in glaucoma

OBJECTIVES

This cross-sectional study aimed to investigate the relationship between visual function and staircase use in glaucoma.

METHODS

Overall, 181 patients with glaucoma with a best-corrected visual acuity ≥20/400 were classified into mild to moderate (mean deviation [MD] ≥ -12 dB) and advanced (MD < -12 dB) groups, according to 24-2 VF of the worse eye. Staircase use evaluation included stair descent and ascent time (SDT/SAT) and self-reported stair difficulty. Correlations between staircase use and visual function were analysed, including binocular visual acuity, integrated visual field (IVF), and binocular contrast sensitivity (CS). Linear and logistic regression adjusted by age, sex, and comorbidities inspected the effect of visual parameters on SDT/ SAT and stair difficulty.

RESULTS

Visual function best correlated with SDT among staircase use. In mild to moderate glaucoma, area under the log CS function (AULCSF) (β = -1.648, P = 0.031) was the only visual factor significant for SDT (adjusted R2 = 0.106), whereas AULCSF (β = -1.641, P = 0.048) and MD of IVFINF0-24 (β = -0.089, P = 0.013) were associated with SDT in advanced glaucoma (adjusted R2 = 0.589). The AULCSF was the only significant visual parameter related to SAT (β = -1.125, P = 0.019) and stair difficulty (adjusted odds ratio = 0.003; 95% confidence interval, 0-0.302; P = 0.013).

CONCLUSIONS

SDT provides a higher correlation with visual function than self-reported stair difficulty. Patients with impaired CS or inferior IVF defects should be advised on stair safety and referred to low-vision services.

Comparing a head-mounted virtual reality perimeter and the Humphrey Field Analyzer for visual field testing in healthy and glaucoma patients

PURPOSE

To compare clinical visual field outputs in glaucoma and healthy patients returned by the Humphrey Field Analyzer (HFA) and virtual reality (Virtual Field, VF) perimetry.

METHODS

One eye of 54 glaucoma patients and 41 healthy subjects was prospectively tested (three times each in random order) using the HFA and VF perimeters (24-2 test grids). We extracted and compared global indices (mean deviation [MD] and pattern standard deviation [PSD]), pointwise sensitivity (and calculated 'equivalent' sensitivity after accounting for differences in background luminance) and pointwise defects. Bland-Altman (mean difference [Mdiff ] and 95% limits of agreement [LoA]) and intraclass correlation analyses were performed.

RESULTS

The VF test was shorter (by 76 s) and had lower fixation losses (by 0.08) and false-positive rate (by 0.01) compared to the HFA (all p < 0.0001). Intraclass correlations were 0.86, 0.82 and 0.47 for MD, PSD and pointwise sensitivity between devices, respectively. Test-retest variability was higher for VF (Mdiff 0.3 dB, LoA -7.6 to 8.2 dB) compared to the HFA (Mdiff -0.3 dB, LoA -6.4 to 5.9 dB), indicating greater test-retest variability. When using each device's underlying normative database, the HFA detected, on average, 7 more defects (at the p < 0.05 level) out of the 52 test locations compared to this iteration of VF in the glaucoma cohort.

CONCLUSIONS

Virtual Field returns global results that are correlated with the HFA, but pointwise sensitivities were more variable. Differences in test-retest variability and defect detection by its current normative database raise questions about the widespread adoption of VF in lieu of the HFA.

Utility of Central 10 Degrees Visual Field Test With Size V Stimulus in End-Stage Glaucoma

PRCIS

In end-stage glaucoma, the central 10-degree visual field test with a size V stimulus provided useful information, including the number of points with detectable retinal sensitivity threshold values and retinal sensitivity threshold values.

PURPOSE

The purpose of this study was to evaluate the clinical utility of the central 10-degree visual field test with a size V stimulus in end-stage glaucoma.

MATERIALS AND METHODS

A total of 73 eyes with end-stage glaucoma (visual field limited to a radius of <10 degrees from fixation) were included. Central 10 degrees visual field tests were performed using both size III and V stimuli. Reliability indices, test duration, number of points with detectable retinal sensitivity threshold values, and retinal sensitivity threshold values at 4 central points, 4 quadrants, and 3 clusters (papillomacular area, superior half, and inferior half) were compared between the test results using size III and V stimuli.

RESULTS

When the size V stimulus was used, the mean test duration increased from 7.8 to 13.3 minutes ( P < 0.001), the mean number of test points with detectable retinal sensitivity threshold values in total area increased from 19.0 to 37.3 ( P < 0.001), and the mean retinal sensitivity threshold values in total area increased from 3.9 to 9.3 dB ( P < 0.001) compared with the test results with the size III stimulus. Significant increase in the visual field parameters was found in all quadrants and clusters ( P < 0.001), and a greater increase was associated with better visual acuity and greater mean deviation of the visual field ( P < 0.05).

CONCLUSIONS

The central 10-degree visual field test with a size V stimulus provided more information than the test with a size III stimulus in end-stage glaucoma.

Validation of the RCOphth and UKEGS glaucoma risk stratification tool 'GLAUC-STRAT-fast'

BACKGROUND/AIMS

The aim of this study was to validate the Glaucoma Risk Stratification Tool (GLAUC-STRAT-fast) currently recommended by the Royal College of Ophthalmologists for the risk stratification of patients with glaucoma in the UK National Health Service Hospital Eye Service.

METHODS

GLAUC-STRAT fast was applied to the LiGHT trial participants by risk-stratifying the worse eye of each patient at baseline and after 3 years of treatment. Metrics of disease severity or treatment intensity used for the validation were: increased number of monitoring visits or treatment escalations; needing a trabeculectomy; a reduction of >2 dB in visual field mean deviation (VF MD) during the monitoring period; identification of rapid VF loss on total (TD) and/or pattern deviation (PD). The proportion of eyes within each baseline stratum for each of the above markers was compared against the other strata, using a χ2 test for proportions.

RESULTS

There was an association between the baseline stratification and the number of treatment escalations needed to maintain the eye-specific target intraocular pressure (p=0.001), the number of visits needed throughout the 3-year follow-up period (p=0.001), the need for trabeculectomy (p<0.001) and absolute loss of MD over the course of the monitoring period (p<0.001). The rate of VF progression was not associated with baseline risk stratification for TD or PD progression (p≥0.007, with Bonferroni correction).

CONCLUSION

The GLAUC-STRAT fast tool is a useful tool for risk stratifying eyes with ocular hypertension or open angle glaucoma. Further research is needed to confirm and validate its applicability to more advanced glaucomas and generalisability to clinical use.

TRIAL REGISTRATION NUMBER

The LiGHT trial is registered at controlled-trials.com (ISRCTN32038223).

Three-Dimensional Structural Phenotype of the Optic Nerve Head as a Function of Glaucoma Severity

Importance

The 3-dimensional (3-D) structural phenotype of glaucoma as a function of severity was thoroughly described and analyzed, enhancing understanding of its intricate pathology beyond current clinical knowledge.

Objective

To describe the 3-D structural differences in both connective and neural tissues of the optic nerve head (ONH) between different glaucoma stages using traditional and artificial intelligence-driven approaches.

Design, Setting, and Participants

This cross-sectional, clinic-based study recruited 541 Chinese individuals receiving standard clinical care at Singapore National Eye Centre, Singapore, and 112 White participants of a prospective observational study at Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania. The study was conducted from May 2022 to January 2023. All participants had their ONH imaged using spectral-domain optical coherence tomography and had their visual field assessed by standard automated perimetry.

Main Outcomes and Measures

(1) Clinician-defined 3-D structural parameters of the ONH and (2) 3-D structural landmarks identified by geometric deep learning that differentiated ONHs among 4 groups: no glaucoma, mild glaucoma (mean deviation [MD], ≥-6.00 dB), moderate glaucoma (MD, -6.01 to -12.00 dB), and advanced glaucoma (MD, <-12.00 dB).

Results

Study participants included 213 individuals without glaucoma (mean age, 63.4 years; 95% CI, 62.5-64.3 years; 126 females [59.2%]; 213 Chinese [100%] and 0 White individuals), 204 with mild glaucoma (mean age, 66.9 years; 95% CI, 66.0-67.8 years; 91 females [44.6%]; 178 Chinese [87.3%] and 26 White [12.7%] individuals), 118 with moderate glaucoma (mean age, 68.1 years; 95% CI, 66.8-69.4 years; 49 females [41.5%]; 97 Chinese [82.2%] and 21 White [17.8%] individuals), and 118 with advanced glaucoma (mean age, 68.5 years; 95% CI, 67.1-69.9 years; 43 females [36.4%]; 53 Chinese [44.9%] and 65 White [55.1%] individuals). The majority of ONH structural differences occurred in the early glaucoma stage, followed by a plateau effect in the later stages. Using a deep neural network, 3-D ONH structural differences were found to be present in both neural and connective tissues. Specifically, a mean of 57.4% (95% CI, 54.9%-59.9%, for no to mild glaucoma), 38.7% (95% CI, 36.9%-40.5%, for mild to moderate glaucoma), and 53.1 (95% CI, 50.8%-55.4%, for moderate to advanced glaucoma) of ONH landmarks that showed major structural differences were located in neural tissues with the remaining located in connective tissues.

Conclusions and Relevance

This study uncovered complex 3-D structural differences of the ONH in both neural and connective tissues as a function of glaucoma severity. Future longitudinal studies should seek to establish a connection between specific 3-D ONH structural changes and fast visual field deterioration and aim to improve the early detection of patients with rapid visual field loss in routine clinical care.

Post-Illumination Pupil Response and Sleep Quality in Patients With Glaucoma: The LIGHT Study

Purpose

This study aimed to investigate whether intrinsically photosensitive retinal ganglion cell function evaluated using post-illumination pupil response (PIPR) in patients with glaucoma is associated with sleep quality.

Methods

This cross-sectional study measured the PIPR in 138 patients with glaucoma (mean age, 70.3 years) using pupil diameter after red and blue light exposure. The net PIPR change was classified into three groups according to tertiles (i.e., low, intermediate, and high groups), with lower net PIPR change indicating lower intrinsically photosensitive retinal ganglion cell (ipRGC) function. Subjective and objective sleep qualities were assessed using the Pittsburgh Sleep Quality Index (PSQI) questionnaire and actigraphy, respectively, with a total PSQI score of ≥6 indicating sleep disturbance.

Results

The prevalence of subjective sleep disturbance significantly increased with decreasing tertile groups of net PIPR change (P = 0.036). Subgroup analysis obtained the same results in the severe glaucoma group (P = 0.004) but not in the non-severe glaucoma group. In the severe glaucoma group, multivariable logistic regression analysis adjusted for potential confounders showed a higher odds ratio for subjective sleep disturbance in the low-tertile group of net PIPR compared with the high-tertile group (odds ratio = 6.22; 95% confidence interval, 1.76-21.90; P = 0.004). Significant associations between PIPR and objective sleep quality (total sleep time, sleep efficiency, and wake after sleep onset) were found in the severe glaucoma group (P = 0.015, P = 0.013, and P = 0.015, respectively).

Conclusions

The PIPR in patients with glaucoma was significantly associated with decreased sleep quality, independent of potential confounders.

Multiple (frontloaded) visual field tests increase identification of very slow mean deviation progression in glaucoma

OBJECTIVE

To determine the effect of frontloading (multiple) visual field (VF) tests at the same visit for detecting mean deviation (MD) change in slowly progressive glaucoma.

METHODS

This was a computer simulation study. Baseline MD (range, 0 to -12 dB) and progression rate (range, 0 to -0.4 dB/year, non-inclusive) were generated for 10,000 patients. Each patient had 6 simulated "stable" baseline VF tests. Then follow-up VFs (up to 10 years) were generated by incorporating progression rate and within-visit and between-visit variability. The independent variables were number of VF tests per visit (one non-frontloaded or two frontloaded), VF reliability (100%, 85%, or 70%), repeat testing because of unreliable results (yes or no), and follow-up interval (6-monthly or yearly). The outcomes were detection of progression (MD slope that was negative and significant at p < 0.05), MD at detection, and number of years to detection.

RESULTS

Frontloading identified more progressors (62.7%-79.2%) compared with non-frontloading (31.0%-36.7%) at 10 years (p < 0.0001). Six-monthly follow-ups led to greater detection than yearly intervals. Progressors detected by both methods were detected by the non-frontloaded method sooner (up to 0.26 years), but this was small and not clinically significant (MD difference, 0.06 dB). An increase (less severe) in MD, an increase (slower) in progression rate, and an increase in SD of baseline VFs decreased the likelihood of detecting progression.

CONCLUSIONS

Frontloading VF tests at 6-monthly intervals improve detection rates of MD progression in slowly progressive glaucoma patients compared with performing 1 test per visit at yearly intervals.

24-Hour efficacy of single primary selective laser trabeculoplasty versus latanoprost eye drops for Naïve primary open-angle glaucoma and ocular hypertension patients

This prospective, observer-masked, randomized clinical trial was conducted between December 2018 and June 2021 at Eye Hospital, China Academy of Chinese Medical Sciences. A total of 45 glaucoma patients from Beijing, China, were enrolled in this clinical trial to compare the short-term efficacy of primary single-selective laser trabeculoplasty (SLT) to 0.005% latanoprost eye drops for the treatment of 24-h intraocular pressure (IOP) in patients with newly diagnosed primary open angle glaucoma (POAG) and ocular hypertension (OHT). Both SLT and latanoprost significantly decreased mean 24-h IOP and peak IOP, although the latanoprost group effect was more potent when compared to the SLT group (both Ps < 0.05). Compared with the SLT group, the latanoprost group had a significant and stable decrease in IOP after treatment. The latanoprost group had a more pronounced reduction in IOP at weeks 4 and 12 (P < 0.05) but had no difference at week 1 (P = 0.097). As a first-line treatment, both SLT and latanoprost eye drops are effective in newly diagnosed POAG and OHT patients. However, the latanoprost eye drops may be better in decreasing mean and peak 24-h IOP and thus controlling 24-h IOP fluctuation compared to SLT.

Diurnal change of retinal vessel density related to hemodynamic variation in treatment-naïve low-teens normal-tension glaucoma

This study undertook to investigate the diurnal variation of optical coherence tomography angiography (OCTA) -derived retinal vessel density (RVD) in glaucoma patients with low baseline intraocular pressure (IOP). A prospective evaluation was performed on low-teens normal-tension glaucoma (low-teens NTG) patients with pre-treatment IOP < 15 mmHg and 32 healthy subjects. Superficial peripapillary and macular RVD by OCTA, IOP, and systemic blood pressure (BP) were all measured four times per day (from 9:00 a.m. to 6:00 p.m.). In the low-teens NTG group, the magnitude of diurnal changes in peripapillary RVD and macular RVD were greater than those in the healthy group. Diurnal variations of diastolic BP (DBP) and mean ocular perfusion pressure (MOPP) also were greater in the low-teens NTG group. As for the patterns of diurnal RVD change, the inferior and temporal sections of macular RVD showed significant differences between the two groups. Diurnal changes of RVD and MOPP and were greater than those in healthy eyes. The macular RVD and MOPP showed different diurnal patterns between the two groups. From these findings, OCTA-derived RVD variation could be related to hemodynamic variability in low-teens NTG.

Diagnostic accuracy of an iPad application for detection of visual field defects

BACKGROUND/OBJECTIVES

Tablet-based perimetry could be used to test for glaucomatous visual field defects in settings without easy access to perimeters, although few studies have assessed diagnostic accuracy of tablet-based tests. The goal of this study was to determine the diagnostic accuracy of iPad perimetry using the visualFields Easy application.

SUBJECTS/METHODS

This was a prospective, cross-sectional study of patients undergoing their first Humphrey Field Analyser (HFA) visual field test at a glaucoma clinic in India. Participants underwent 24-2 SITA Standard HFA testing and iPad-based perimetry with the visualFields Easy application. Reference standards for both visual field loss and suspected glaucoma were determined by ophthalmologist review of HFA results and optic disc photographs. Receiver operating characteristic curves were constructed to assess diagnostic accuracy at various test thresholds.

RESULTS

203 eyes from 115 participants were included, with 82 eyes classified as moderate or worse glaucoma. iPad perimetry had an area under the receiver operating characteristic (AUROC) curve of 0.64 (95% CI 0.57 to 0.71) for detection of any visual field defect relative to HFA and an AUROC of 0.68 (0.59 to 0.76) for detection of moderate or worse glaucoma relative to ophthalmologist examination. At a set specificity of 90%, the sensitivity of iPad perimetry for detection of moderate or worse glaucoma was 35% (22-48%).

CONCLUSIONS

iPad perimetry using the visualFields Easy application had inadequate diagnostic accuracy to be used as a screening tool for glaucoma in this South Indian population.

[Assessment of a pupillometric method for the screening of glaucoma]

BACKGROUND

Glaucoma is a progressive optic neuropathy, remaining asymptomatic for a long time, which makes its early diagnosis difficult. Visual field testing is still the gold standard but is less than ideal. The goal of this study is to assess a pupillometric test, administered passively to the subject for one minute, to measure its sensitivity and specificity in the classification of healthy eyes and glaucomatous eyes, and to evaluate its tolerability compared to visual field testing.

METHODS

Forty-five participants were included in this single-center, interventional, prospective study. They underwent 3 monocular pupillometric tests with light stimulation: 6 pupillary responses were recorded during full-field multifocal stimulation (performed twice) and pupillary hippus cycle study.

RESULTS

Analysis of spectral power and pupillary measurements with full-field multifocal stimulation provides a 0.94 sensitivity and a 0.88 specificity, a virtually perfect discrimination for early stages of glaucoma. Analysis of pupil cycle time provides a 0.92 sensitivity and a 0.88 specificity for early stages. Acceptability of this test by patients is superior to visual field testing.

CONCLUSION

These results show that data from our pupillometric recordings provide a good classification of healthy and glaucomatous eyes and must be confirmed on a larger population.

Optical Coherence Tomography Angiography of the Retinal Circulation Following Trabeculectomy for Glaucoma

PRCIS

Despite successful trabeculectomy, eyes with similar levels of peripapillary and macular vessel densities but with worse preoperative visual field mean deviations may experience functional and vascular decline after surgery.

PURPOSE

To evaluate the retinal microcirculation change after trabeculectomy according to glaucoma severity using optical coherence tomography angiography (OCTA).

METHODS

We enrolled 59 eyes of primary open angle glaucoma patients who underwent trabeculectomy. The eyes were categorized into 3 groups by preoperative visual field (VF) mean deviation (MD), group 1: MD>-12.0 dB, group 2: MD -12.0 to -20.0 dB, and group 3: MD <-20.0 dB. OCTA was performed preoperatively and 1 year after trabeculectomy. The differences in the radial peripapillary capillary vessel density (pVD) and macular VD between preoperative and postoperative assessment were analyzed and compared in each group. Factors associated with the VD change after trabeculecomy were determined using linear regression analysis.

RESULTS

Mean postoperative IOP and IOP reduction did not differ among the 3 groups after trabeculectomy. Preoperative pVD (37.2 vs. 36.6%, P =1.00) and macular VD (39.0 vs. 38.4%, P =1.00) did not differ between groups 1 and 2. Group 1 and 3 showed no changes in VD parameters after trabeculectomy (all, P >0.05). However, group 2 showed statistically significant decreases in pVD (36.6 vs. 32.9%, P <0.001) and macular VD (38.4 vs. 36.0%, P =0.010) after trabeculectomy. The reduction of pVD was associated with a decrease of IOP (Coefficient (β); 0.14, P =0.032) and VF MD (β; 0.15, P =0.0116) in group 2, respectively.

CONCLUSION

Following successful trabeculectomy surgery for uncontrolled glaucoma with similar IOP reduction, glaucoma eyes with advanced visual field loss showed reduced pVD and macular VD measured by OCT-A. These findings may be relevant to disease progression.

Usability and Clinician Acceptance of a Deep Learning-Based Clinical Decision Support Tool for Predicting Glaucomatous Visual Field Progression

PRCIS

We updated a clinical decision support tool integrating predicted visual field (VF) metrics from an artificial intelligence model and assessed clinician perceptions of the predicted VF metric in this usability study.

PURPOSE

To evaluate clinician perceptions of a prototyped clinical decision support (CDS) tool that integrates visual field (VF) metric predictions from artificial intelligence (AI) models.

METHODS

Ten ophthalmologists and optometrists from the University of California San Diego participated in 6 cases from 6 patients, consisting of 11 eyes, uploaded to a CDS tool ("GLANCE", designed to help clinicians "at a glance"). For each case, clinicians answered questions about management recommendations and attitudes towards GLANCE, particularly regarding the utility and trustworthiness of the AI-predicted VF metrics and willingness to decrease VF testing frequency.

MAIN OUTCOMES AND MEASURES

Mean counts of management recommendations and mean Likert scale scores were calculated to assess overall management trends and attitudes towards the CDS tool for each case. In addition, system usability scale scores were calculated.

RESULTS

The mean Likert scores for trust in and utility of the predicted VF metric and clinician willingness to decrease VF testing frequency were 3.27, 3.42, and 2.64, respectively (1=strongly disagree, 5=strongly agree). When stratified by glaucoma severity, all mean Likert scores decreased as severity increased. The system usability scale score across all responders was 66.1±16.0 (43rd percentile).

CONCLUSIONS

A CDS tool can be designed to present AI model outputs in a useful, trustworthy manner that clinicians are generally willing to integrate into their clinical decision-making. Future work is needed to understand how to best develop explainable and trustworthy CDS tools integrating AI before clinical deployment.

Laser in Glaucoma and Ocular Hypertension (LiGHT) Trial: Six-Year Results of Primary Selective Laser Trabeculoplasty versus Eye Drops for the Treatment of Glaucoma and Ocular Hypertension

PURPOSE

The Laser in Glaucoma and Ocular Hypertension (LiGHT) Trial has shown selective laser trabeculoplasty (SLT) to be clinically and cost-effective as a primary treatment of open-angle glaucoma (OAG) and ocular hypertension (OHT) at 3 years. This article reports health-related quality of life (HRQoL) and clinical effectiveness of initial treatment with SLT compared with intraocular pressure (IOP)-lowering eye drops after 6 years of treatment.

DESIGN

Prospective, multicenter randomized controlled trial.

PARTICIPANTS

Treatment-naive eyes with OAG or OHT initially treated with SLT or IOP-lowering drops.

METHODS

Patients were allocated randomly to initial SLT or eye drops. After the initial 3 years of the trial, patients in the SLT arm were permitted a third SLT if necessary; patients in the drops arm were allowed SLT as a treatment switch or escalation. This study is registered at controlled-trials.com (identifier, ISRCTN32038223).

MAIN OUTCOME MEASURES

The primary outcome was HRQoL at 6 years; secondary outcomes were clinical effectiveness and adverse events.

RESULTS

Of the 692 patients completing 3 years in the LiGHT Trial, 633 patients (91.5%) entered the extension, and 524 patients completed 6 years in the trial (82.8% of those entering the extension phase). At 6 years, no significant differences were found for the EuroQol EQ-5D 5 Levels, Glaucoma Utility Index, and Glaucoma Quality of Life-15 (P > 0.05 for all). The SLT arm showed better Glaucoma Symptom Scale scores than the drops arm (83.6 ± 18.1 vs. 81.3 ± 17.3, respectively). Of eyes in the SLT arm, 69.8% remained at or less than the target IOP without the need for medical or surgical treatment. More eyes in the drops arm exhibited disease progression (26.8% vs. 19.6%, respectively; P = 0.006). Trabeculectomy was required in 32 eyes in the drops arm compared with 13 eyes in the SLT arm (P < 0.001); more cataract surgeries occurred in the drops arm (95 compared with 57 eyes; P = 0.03). No serious laser-related adverse events occurred.

CONCLUSIONS

Selective laser trabeculoplasty is a safe treatment for OAG and OHT, providing better long-term disease control than initial drop therapy, with reduced need for incisional glaucoma and cataract surgery over 6 years.

A latanoprost cationic emulsion (STN1013001) vs. other latanoprost formulations (Latanoprost) in open angle glaucoma/ocular hypertension and ocular surface disease: an Italian cost-utility analysis

BACKGROUND

STN1013001 is an innovative latanoprost cationic emulsion for open-angle glaucoma/ocular hypertension (OAG/OHT) and ocular surface disease (OSD).

METHODS AND FINDINGS

A 5-year, 7 health states, 1-year cycle early Markov model-supported cost-utility analysis (CUA) of STN1013001 vs. other latanoprost formulations (Latanoprost) followed the Italian National Health Service (INHS) perspective.One-way, probabilistic and scenario sensitivity analyses tested the uncertainty of the baseline results. Value of information analysis (VOIA) investigated the potential cost-effectiveness of collecting further evidence.

RESULTS

Over 5 years, the Markov model-supported CUA predicts STN1013001 to be potentially highly cost-effective vs. Latanoprost (+€57.60 cost at €2020 values; +0.089 Quality-Adjusted Life Years).The Incremental Cost-Utility Ratio (€647.65) falls well below the lower limit of the acceptability range proposed for Italy (€25,000-€40,000).Sensitivity analyses confirmed the robustness of the baseline findings. VOIA highlighted that further information might only be cost-effective for OAG/OHT utilities and OSD-related disutility.

CONCLUSION

STN1013001 is potentially highly cost-effective and strongly dominant vs. Latanoprost for OAG/OHT+OSD patients from the INHS perspective. These findings should be re-assessed using the data from the ongoing Phase III trial (NCT04133311) comparing the efficacy and safety of STN1013001 vs. Latanoprost and with future real-world CUAs upon the availability of STN1013001 on the Italian market.

Threat to fixation and vision-related quality of life in early open-angle glaucoma - results from the Glaucoma Intensive Treatment Study

PURPOSE

To determine the effect of glaucomatous visual field (VF) damage close to the point of fixation, called threat-to-fixation (TTF), on vision-related quality of life (VRQoL) in open-angle glaucoma.

METHODS

A total of 239 patients from the Glaucoma Intensive Treatment Study (GITS) were included in this analysis. The second VF of patients with newly diagnosed primarily early glaucoma was evaluated for the presence or absence of TTF. TTF was defined as VF loss including one or more of the four innermost test points depressed at p < 1% in the total deviation probability map of Humphrey 24-2 SITA Standard visual fields. VRQoL was evaluated using Rasch-analysed National Eye Institute Visual Function Questionnaire 25 (NEI VFQ-25) scores. The correlation between VRQoL and TTF was evaluated using uni- and multivariable regression analyses.

RESULTS

TTF was present in at least one eye in 115 patients (48%); located in the superior hemifield alone in 47% (54 of 115), in the inferior hemifield alone in 23% (27 of 115), and in 30% (34 of 115) in both hemifields. The median Rasch-calibrated NEI VFQ-25 scores were identical when comparing patients with TTF (VRQoL score 66, 95% CI: 23-100) and those with no-TTF (VRQoL score 66, 95% CI: 21-100) (p = 0.925). Neither the presence of TTF (R²  = -0.004, p = 0.968) nor the location of TTF (R²  = 0.023, p = 0.103) was significantly correlated to Rasch-calibrated NEI VFQ-25 scores.

CONCLUSION

The presence of TTF did not influence VRQoL, as measured by the NEI-VFQ-25, in this relatively large group of patients with mainly early glaucoma.

Geometric Deep Learning to Identify the Critical 3D Structural Features of the Optic Nerve Head for Glaucoma Diagnosis

PURPOSE

To compare the performance of 2 relatively recent geometric deep learning techniques in diagnosing glaucoma from a single optical coherence tomographic (OCT) scan of the optic nerve head (ONH); and to identify the 3-dimensional (3D) structural features of the ONH that are critical for the diagnosis of glaucoma.

DESIGN

Comparison and evaluation of deep learning diagnostic algorithms.

METHODS

In this study, we included a total of 2247 nonglaucoma and 2259 glaucoma scans from 1725 participants. All participants had their ONHs imaged in 3D with Spectralis OCT. All OCT scans were automatically segmented using deep learning to identify major neural and connective tissues. Each ONH was then represented as a 3D point cloud. We used PointNet and dynamic graph convolutional neural network (DGCNN) to diagnose glaucoma from such 3D ONH point clouds and to identify the critical 3D structural features of the ONH for glaucoma diagnosis.

RESULTS

Both the DGCNN (area under the curve [AUC]: 0.97±0.01) and PointNet (AUC: 0.95±0.02) were able to accurately detect glaucoma from 3D ONH point clouds. The critical points (ie, critical structural features of the ONH) formed an hourglass pattern, with most of them located within the neuroretinal rim in the inferior and superior quadrant of the ONH.

CONCLUSIONS

The diagnostic accuracy of both geometric deep learning approaches was excellent. Moreover, we were able to identify the critical 3D structural features of the ONH for glaucoma diagnosis that tremendously improved the transparency and interpretability of our method. Consequently, our approach may have strong potential to be used in clinical applications for the diagnosis and prognosis of a wide range of ophthalmic disorders.

Assessing the external validity of machine learning-based detection of glaucoma

Studies using machine learning (ML) approaches have reported high diagnostic accuracies for glaucoma detection. However, none assessed model performance across ethnicities. The aim of the study is to externally validate ML models for glaucoma detection from optical coherence tomography (OCT) data. We performed a prospective, cross-sectional study, where 514 Asians (257 glaucoma/257 controls) were enrolled to construct ML models for glaucoma detection, which was then tested on 356 Asians (183 glaucoma/173 controls) and 138 Caucasians (57 glaucoma/81 controls). We used the retinal nerve fibre layer (RNFL) thickness values produced by the compensation model, which is a multiple regression model fitted on healthy subjects that corrects the RNFL profile for anatomical factors and the original OCT data (measured) to build two classifiers, respectively. Both the ML models (area under the receiver operating [AUC] = 0.96 and accuracy = 92%) outperformed the measured data (AUC = 0.93; P < 0.001) for glaucoma detection in the Asian dataset. However, in the Caucasian dataset, the ML model trained with compensated data (AUC = 0.93 and accuracy = 84%) outperformed the ML model trained with original data (AUC = 0.83 and accuracy = 79%; P < 0.001) and measured data (AUC = 0.82; P < 0.001) for glaucoma detection. The performance with the ML model trained on measured data showed poor reproducibility across different datasets, whereas the performance of the compensated data was maintained. Care must be taken when ML models are applied to patient cohorts of different ethnicities.

Automated macular segmentation can distinguish glaucomatous from compressive optic neuropathy

PURPOSE

To compare macular damage in glaucomatous optic neuropathy (GON) and compressive optic neuropathy (CON) and assess its diagnostic accuracy in distinguishing between diseases.

METHODS

Observational, cross-sectional, single-center study. Patients with GON, CON, and healthy controls were included according to the eligibility criteria. An automated spectral-domain optical coherence tomography (SD-OCT) algorithm was used to segment the circumpapilary retinal nerve fiber layer (cpRNFL) and macula. The layer thickness was measured in each sector according to the Early Treatment Diabetic Retinopathy Study and the 6-sector Garway-Heath-based grids. Data was compared across all study groups, and the significance level was set at 0.05.

RESULTS

Seventy-five eyes of 75 participants, 25 with GON, 25 with CON, and 25 healthy controls (CG), were included. Macular thickness was diminished in the ganglion cell complex of GON and CON patients compared to CG (p<0.05). The best Garway-Heath-based grid parameters for distinguishing GON and CON were the nasal-inferior (NI) and nasal-superior sectors and the NI/temporal inferior (TI) damage ratios in the macular ganglion cell (mGCL) and inner plexiform (IPL) layers. Moreover, the combination of the NI sector and NI/TI damage ratios in both layers had higher discriminative power (AUC 0.909; 95% CI 0.830-0.988; p<0.001) than combining parameters in each layer separately.

CONCLUSION

Our findings suggest that the evaluation of macular segmented layers damage by SD-OCT may be a helpful add-on tool in the differential diagnosis between GON and CON.

Burden of Glaucoma in the United Kingdom: A Multicenter Analysis of United Kingdom Glaucoma Services

OBJECTIVE

To determine the spectrum of glaucoma-associated health care resource utilization among outpatients attending National Health Service (NHS) hospital glaucoma clinics and the costs of managing glaucoma in this setting.

DESIGN

Retrospective observational cohort study using electronic medical record data.

SUBJECTS

Patients aged ≥ 18 years attending 5 NHS glaucoma clinics in the United Kingdom (2013‒2018) with ≥ 12 months of continuous electronic medical record data.

METHODS

Deidentified Medisoft Ophthalmology electronic medical record data (January 2013‒December 2018) from 43 742 eligible patients were categorized by year of clinic visit. Extracted information included patient demographics, glaucoma diagnoses, topical glaucoma medication prescription start/stop dates, types/numbers of glaucoma clinic visits, glaucoma investigations (visual acuity, intraocular pressure, visual field, and OCT), and glaucoma procedures received over 12 months after the first ("index") visit of the specified year. Direct glaucoma-related health care costs (clinic visits, investigations, procedures, and ongoing glaucoma medication initiated in the clinic) were estimated from event volumes and unit costs (UK national tariffs) and expressed from the direct-payer perspective.

MAIN OUTCOME MEASURES

Glaucoma diagnoses and topical glaucoma medication use at the index clinic visit; numbers of glaucoma clinic visits, investigations and procedures; and glaucoma-related health care costs over 12 months postindex.

RESULTS

For the 2016 cohort (n = 21 719), the estimated average total cost of NHS-provided glaucoma care over 12 months was £405 per patient (medical staff services £209, glaucoma investigations £126, glaucoma medication £40, glaucoma procedures £26). Among this cohort, 40.8% had ocular hypertension/suspected glaucoma, 70% had 0-to-mild visual field impairment, and 14% had undergone a glaucoma procedure. Over 12 months, patients received (mean) 2.0 glaucoma clinic visits and 1.5 visual field tests, and 7% underwent glaucoma procedure(s). Results were similar for the other years examined.

CONCLUSIONS

Cost estimates for managing patients with glaucoma in the UK are required for effective service planning. Appreciable proportions of patients managed in NHS glaucoma clinics may be considered at low risk of blindness (glaucoma suspects and those with ocular hypertension with mild visual field loss) and may be more appropriately managed with alternative, more affordable models of care.

Advanced glaucoma. Clinical practice guideline

OBJECTIVE

To present an update clinical practice guideline that serve as a guide for the detection, evaluation and treatment of adults patients with advanced glaucoma.

METHODS

After defining the objectives and scope of the guide, the working group was formed and structured clinical questions were formulated following the PICO (Patient, Intervention, Comparison, Outcomes) format. Once all the existing clinical evidence had been independently evaluated with the AMSTAR 2 (Assessment of Multiple systematic Rewiews) and Cochrane "Risk of bias" tools by at least two reviewers, recommendations were formulated following the Scottish Intercollegiate methodology. Guideline Network (SIGN).

RESULTS

Recommendations with their corresponding levels of evidence that may be useful in the diagnosis, monitoring and treatment of adults patients with advanced glaucoma.

CONCLUSIONS

Despite the fact that for many of the questions the level of scientific evidence available is not very high, this clinical practice guideline offers an updated review of the different existing aspects related to the evaluation and management of advanced glaucoma.

High sampling resolution optical coherence tomography reveals potential concurrent reductions in ganglion cell-inner plexiform and inner nuclear layer thickness but not in outer retinal thickness in glaucoma

PURPOSE

To analyse optical coherence tomography (OCT)-derived inner nuclear layer (INL) and outer retinal complex (ORC) measurements relative to ganglion cell-inner plexiform layer (GCIPL) measurements in glaucoma.

METHODS

Glaucoma participants (n = 271) were categorised by 10-2 visual field defect type. Differences in GCIPL, INL and ORC thickness were calculated between glaucoma and matched healthy eyes (n = 548). Hierarchical cluster algorithms were applied to generate topographic patterns of retinal thickness change, with agreement between layers assessed using Cohen's kappa (κ). Differences in GCIPL, INL and ORC thickness within and outside GCIPL regions showing the greatest reductions and Spearman's correlations between layer pairs were compared with 10-2 mean deviation (MD) and pattern standard deviation (PSD) to determine trends with glaucoma severity.

RESULTS

Glaucoma participants with inferior and superior defects presented with concordant GCIPL and INL defects demonstrating mostly fair-to-moderate agreement (κ = 0.145-0.540), which was not observed in eyes with no or ring defects (κ = -0.067-0.230). Correlations (r) with MD and PSD were moderate and weak in GCIPL and INL thickness differences, respectively (GCIPL vs. MD r = 0.479, GCIPL vs. PSD r = -0.583, INL vs. MD r = 0.259, INL vs. PSD r = -0.187, p = <0.0001-0.002), and weak in GCIPL-INL correlations (MD r = 0.175, p = 0.004 and PSD r = 0.154, p = 0.01). No consistent patterns in ORC thickness or correlations were observed.

CONCLUSIONS

In glaucoma, concordant reductions in macular INL and GCIPL thickness can be observed, but reductions in ORC thickness appear unlikely. These findings suggest that trans-synaptic retrograde degeneration may occur in glaucoma and could indicate the usefulness of INL thickness in evaluating glaucomatous damage.

Safety and Efficacy of the Preserflo® Microshunt in Refractory Glaucoma: A One-Year Study

Purpose: To evaluate the safety and efficacy of Preserflo^® microshunt implantation in eyes with refractory glaucoma. Methods: In this retrospective study, a cohort of patients who underwent Preserflo^® microshunt implantation between April 2019 and August 2020 for refractory glaucoma were evaluated. At the time of surgery, all eyes had uncontrolled intraocular pressure (IOP) despite maximally tolerated medical therapy and at least one previous failed glaucoma filtering surgery. The primary outcome was a complete success, defined as postoperative IOP ≤ 21 mm Hg with an IOP reduction ≥ 20% and no repeat filtering surgery. The secondary outcome was qualified success, defined as a complete success with the use of antiglaucoma medications. The rates of needling, bleb repair, and postoperative complications were also recorded. Results: Forty-seven eyes with a mean preoperative IOP of 30.1 ± 7.1 mm Hg and a mean of 3.4 ± 1 glaucoma medications were included. The mean number of previous surgeries prior to microshunt implantation was 2.3 ± 1.3. After 1 year, the mean IOP was significantly reduced to 18.8 ± 4.6 mm Hg, with the mean number of medications significantly reduced to 1.4 ± 1.2. Complete success was achieved in 35% of eyes, and a qualified success in 60% of eyes. A decrease in IOP of at least 30% was found in 55% of eyes. Needling or bleb repair was performed in 49% of eyes. Complications were minimal and transient, except for one eye which presented with tube extrusion, and another eye with a transected tube. A repeat glaucoma surgery had to be performed in 17% of eyes. Conclusions: The Preserflo^® Microshunt provided moderate success but a significant reduction in IOP, with a good safety profile after one year of follow-up in eyes at high risk for failure of filtering surgery.

Diagnostic Accuracy of Frequency-Doubling Technology and the Moorfields Motion Displacement Test for Glaucoma

PURPOSE

Portable perimetric testing could be useful for community-based glaucoma screening programs. Frequency-doubling technology (FDT) and the Moorfields motion displacement test (MDT) are portable perimeters that have shown promise as potential screening tools for glaucoma. This study's goal was to determine the diagnostic accuracy of FDT and MDT for visual field defects and glaucoma.

DESIGN

Prospective, cross-sectional, diagnostic accuracy study.

PARTICIPANTS

A consecutive series of patients aged ≥ 50 years who presented to a glaucoma clinic in South India and had never undergone Humphrey field analyzer (HFA) visual field testing in the past.

METHODS

Participants underwent 24-2 Swedish Interactive Thresholding Algorithm (SITA) Standard HFA perimetry, FDT perimetry, MDT perimetry, and iPad perimetry using visualFields Easy in random order. Ophthalmologist grades of HFA and optic nerve head photographs were used as reference standards for glaucoma and field defect presence. Receiver operating characteristic curves were constructed to assess the diagnostic accuracy of various parameters for each test.

MAIN OUTCOME MEASURES

Sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC).

RESULTS

Overall, 292 eyes from 173 participants were included, with 112 eyes classified as moderate or worse glaucoma. For moderate or worse glaucoma detection, the best parameter on FDT was mean deviation (MD) (AUROC, 0.84; 95% confidence interval [CI], 0.79-0.89) and the best parameter on MDT was global probability of true damage (GPTD) (AUROC, 0.87; 95% CI, 0.82-0.91). When specificity was set to 90%, the sensitivity for detection of moderate or worse glaucoma was 55% (95% CI, 39%-68%) for FDT MD and 62% (95% CI 52%-71%) for MDT GPTD.

CONCLUSIONS

Frequency-doubling technology and MDT perimetry had fair diagnostic accuracy for glaucoma detection when administered to naïve test takers in this South Indian population. Although not appropriate for use as a sole glaucoma screening test, these perimetric tests may be useful as ancillary tests.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Retinal Microvascular Dysfunction Occurs Early and Similarly in Mild Alzheimer's Disease and Primary-Open Angle Glaucoma Patients

Purpose: To assess the similarities and differences in retinal microvascular function between mild Alzheimer’s disease (AD) patients, early-stage primary open angle glaucoma (POAG) patients and healthy controls. Methods: Retinal vessel reactivity to flickering light was assessed in 10 AD, 19 POAG and 20 healthy age matched control patients by means of dynamic retinal vessel analysis (DVA, IMEDOS, GmbH, Jena, Germany) according to an established protocol. All patients additionally underwent BP measurements and blood analysis for glucose and lipid metabolism markers. Results: AD and POAG patients demonstrated comparable alterations in retinal artery reactivity, in the form of an increased arterial reaction time (RT) to flicker light on the final flicker cycle (p = 0.009), which was not replicated by healthy controls (p > 0.05). Furthermore, the sequential changes in RT on progressing from flicker one to flicker three were found to differ between healthy controls and the two disease groups (p = 0.001). Conclusion: AD and POAG patients demonstrate comparable signs of vascular dysfunction in their retinal arteries at the early stages of their disease process. This provides support for the concept of a common underlying vascular aetiology in these two neurodegenerative diseases.

Racial Differences in Detection of Glaucoma Using Retinal Nerve Fiber Layer Thickness and Bruch Membrane Opening Minimum Rim Width

PURPOSE

To compare the sensitivities and specificities of the retinal nerve fiber layer thickness (RNFLT) and Bruch membrane opening minimum rim width (BMO-MRW) reference database-based criteria for detection of glaucoma in individuals of European descent (ED) and individuals of African descent (AD).

DESIGN

Comparative diagnostic analysis by race METHODS: 382 eyes of 255 glaucoma patients (ED = 170, AD = 85) and 94 eyes of 50 healthy individuals (ED = 30, AD = 20) with global and sectoral RNFLT and BMO-MRW measured with Spectralis optical coherence tomography (OCT) were included. Six diagnostic criteria were evaluated: global measurement below the 5th or 1st percentile, ≥1 of the 6 sector measurements below the 5th or 1st percentile, and superotemporal (ST) and/or inferotemporal (IT) measurement below the 5th or 1st percentile. The sensitivities and specificities of these measurements for detection of glaucoma were compared using bootstrapping methods.

RESULTS

ST and/or IT RNFLT below the 5th percentile has the best performance for detection of glaucoma among RNFLT classifications with a sensitivity (95% CI) of 89.5% (86.1, 92.5) and specificity of 87.2% (77.8, 95.1). In AD individuals, sensitivities of ST and IT RNFLT and BMO-MRW measurements below the 5th percentile criteria were lower than in ED individuals (RNFLT: 83.7% vs 92.5%, and BMO-MRW: 72.1% vs 88.5%, respectively), as well as specificities (AD RNFLT: 73.7% and BMO-MRW: 89.5% vs ED RNFLT: 96.4% and BMO-MRW: 98.2%, respectively).

CONCLUSIONS

RNFLT and BMO-MRW had consistently lower diagnostic performance in AD individuals compared with ED individuals. BMO-MRW criteria might fail to detect as many as one-third of eyes with glaucoma, specifically in AD individuals. With the current reference database, RNFLT, and especially BMO-MRW, criteria are not adequate for diagnosing glaucoma in AD individuals.

Prospective evaluation of wipe-out after glaucoma filtration surgery in eyes with split fixation

Purpose

To assess the incidence and cause of idiopathic, irreversible loss of vision ("wipe-out") in the early post-operative period after glaucoma-filtration surgery in advanced glaucoma.

Methods

It was a prospective, interventional cohort study. Patients with advanced glaucoma and macular split fixation underwent either only trabeculectomy (group A) or combined phaco-emulsification with trabeculectomy (group B). The incidence and cause of visual loss, changes in intra-ocular pressure, visual acuity, and visual field indices during 2 months post surgery were assessed.

Results

Thirty patients (30 eyes) were divided in two groups. No significant difference was noted between the pre-operative and post-operative mean deviations in both groups (P = 0.41, P = 0.65). Two eyes in group A and one eye in group B had visual loss of two lines or more at the end of 2 months because of cataract and choroidal detachment. None of the eyes showed "wipe-out".

Conclusion

"Wipe-out" is a rare phenomenon after surgery in advanced glaucoma.

Socio-Demographic, lifestyle and eye-related factors associated with quality of life Among people with glaucoma in Serbia

PURPOSE

The purpose of this study was to examine socio-demographic, lifestyle and ophthalmological factors associated with poorer Vision Related Quality of Life (VRQoL) in people with glaucoma.

METHODS

This cross-sectional study included 306 consecutive patients with glaucoma who presented for regular check-ups at the referral center in Belgrade (Serbia) from August 2015 to September 2016. The diagnosis of glaucoma was based on the glaucomatous disc cupping and reproducible visual field impairment on one or both eyes. Quality of life was examined using the validated Glaucoma Quality of Life-15 (GQL-15) and the National Eye Institute Visual Function Questionnaire 25 (NEI VFQ 25).

RESULTS

A series of adjusted linear regression models showed that glaucoma patients with higher educational attainment, who were employed and still driving had better VRQoL. Worse visual acuity and visual field defect, being in later glaucoma stages, having lower intraocular pressure, having two laser interventions as well as having pseudo-exfoliative glaucoma was associated with worse VRQoL. Intake of fewer medications and having had no trabeculectomies on better eye as well as taking less drops per day on worse eye were associated with better VRQoL.

CONCLUSIONS

Several socio-demographic, lifestyle and ocular factors can impact VRQoL in glaucoma patients. Identifying people who are at risk of having worse VRQoL could allow for earlier interventions, such as changes in therapy, undergoing surgery, use of mobility aids etc.

Italian Candidates for the XEN Implant: An Overview from the Glaucoma Treatment Registry (XEN-GTR)

Background The Italian XEN Glaucoma Treatment Registry (XEN-GTR) was created to acquire a comprehensive prospective dataset that includes the patient characteristics, intraoperative variables, and postoperative management of glaucoma patients undergoing the XEN gel stent implantation. Methods This was a prospective observational, longitudinal clinical study involving 10 centres throughout Italy. The baseline examination included a comprehensive evaluation of demographic parameters (age, sex, ethnicity, and systemic condition), specific ophthalmological parameters, and quality of life questionnaire score collection. Results The baseline data of 273 patients were analysed. The median (IQR) age was 72 (65.0 to 78.0) years. Of the 273 patients, 123 (45%) were female and 150 (55%) were male. A total of 86% of the patients had open-angle glaucoma with a mean intraocular pressure of 24 ± 6 (range 12.0–60.0) mmHg. The mean number of medications was 2.7 ± 0.9 at baseline for the patients with a prevalence of prostaglandin analogues combined with a beta-blocker and anhydrase carbonic inhibitor (31.8%). The mean scores of the NEI-VFQ 25 and GSS questionnaires were 78 ± 18 (range 26.5–100) and 85 ± 14 (range 79–93), respectively. Combined XEN/cataract surgeries were scheduled in 73.7% of the patients. The preferred place for the XEN implant was the supero-nasal quadrant (91.6%). Conclusions Observing the baseline characteristics of the typical Italian candidates for the XEN gel implant shows that they are patients affected by POAG and cataracts, with moderate to severe glaucoma damage, all of which has an impact on their quality of life.

Comparison of machine learning approaches for structure-function modeling in glaucoma

To evaluate machine learning (ML) approaches for structure-function modeling to estimate visual field (VF) loss in glaucoma, models from different ML approaches were trained on optical coherence tomography thickness measurements to estimate global VF mean deviation (VF MD) and focal VF loss from 24-2 standard automated perimetry. The models were compared using mean absolute errors (MAEs). Baseline MAEs were obtained from the VF values and their means. Data of 832 eyes from 569 participants were included, with 537 Asian eyes for training, and 148 Asian and 111 Caucasian eyes set aside as the respective test sets. All ML models performed significantly better than baseline. Gradient-boosted trees (XGB) achieved the lowest MAE of 3.01 (95% CI: 2.57, 3.48) dB and 3.04 (95% CI: 2.59, 3.99) dB for VF MD estimation in the Asian and Caucasian test sets, although difference between models was not significant. In focal VF estimation, XGB achieved median MAEs of 4.44 [IQR 3.45-5.17] dB and 3.87 [IQR 3.64-4.22] dB across the 24-2 VF for the Asian and Caucasian test sets and was comparable to VF estimates from support vector regression (SVR) models. VF estimates from both XGB and SVR were significantly better than the other models. These results show that XGB and SVR could potentially be used for both global and focal structure-function modeling in glaucoma.

Self-Reported Driving Difficulty, Avoidance, and Negative Emotion With On-Road Driving Performance in Older Adults With Glaucoma

PURPOSE

To investigate the relationship between self-perceived driving difficulty, driving avoidance, and negative emotion about driving with glaucoma severity and on-road driving performance.

DESIGN

Cohort study.

METHODS

Glaucoma patients (n = 111), aged 55 to 90 years, with mild, moderate, and advanced glaucoma in the better-eye based on the Glaucoma Staging System, and age-matched controls (n = 47) were recruited from a large tertiary academic center. Self-reported questionnaires were administered by a trained occupational therapist followed by a standardized on-road driving evaluation (pass vs "at-risk" score) with a masked and certified driving rehabilitation specialist.

RESULTS

Compared to controls, glaucoma participants reported greater driving difficulty with as early as mild glaucoma (P = .0391) and negative emotion about driving starting with moderate glaucoma (P = .0042). Glaucoma participants reporting at least 1 driving difficulty and negative emotion had a 3.3-fold (adjusted odds ratio [OR] = 3.3; 95% CI = 1.24-8.52; P = .0163) and 4.2-fold (adjusted OR = 4.2; 95% CI = 1.5-12.2; P = .0078) greater odds, respectively, of an at-risk score on the on-road test. Self-reported driving difficulty in "difficult" conditions (P = .0019), rain (P = .0096), interstates (P = .0378), and high traffic (P = .0076), driving avoidance on sunny (P = .0065) and cloudy (P = .0043) days, and driving fewer days per week (P = .0329) were also associated with at-risk driving.

CONCLUSIONS

Screening tools that assess self-perceived driving difficulty and driving avoidance in specific conditions, negative emotion about driving, and driving exposure may help identify unsafe drivers with glaucoma. Some of these drivers, particularly those with modest glaucoma, may benefit from a driving evaluation and early referral to resources that could enable them to continue driving safely and confidently.

An Objective and Easy-to-Use Glaucoma Functional Severity Staging System Based on Artificial Intelligence

OBJECTIVE

The objective of this study was to develop an objective and easy-to-use glaucoma staging system based on visual fields (VFs).

SUBJECTS AND PARTICIPANTS

A total of 13,231 VFs from 8077 subjects were used to develop models and 8024 VFs from 4445 subjects were used to validate models.

METHODS

We developed an unsupervised machine learning model to identify clusters with similar VF values. We annotated the clusters based on their respective mean deviation (MD). We computed optimal MD thresholds that discriminate clusters with the highest accuracy based on Bayes minimum error principle. We evaluated the accuracy of the staging system and validated findings based on an independent validation dataset.

RESULTS

The unsupervised k -means algorithm discovered 4 clusters with 6784, 4034, 1541, and 872 VFs and average MDs of 0.0 dB (±1.4: SD), -4.8 dB (±1.9), -12.2 dB (±2.9), and -23.0 dB (±3.8), respectively. The supervised Bayes minimum error classifier identified optimal MD thresholds of -2.2, -8.0, and -17.3 dB for discriminating normal eyes and eyes at the early, moderate, and advanced stages of glaucoma. The accuracy of the glaucoma staging system was 94%, based on identified MD thresholds with respect to the initial k -means clusters.

CONCLUSIONS

We discovered that 4 severity levels based on MD thresholds of -2.2, -8.0, and -17.3 dB, provides the optimal number of severity stages based on unsupervised and supervised machine learning. This glaucoma staging system is unbiased, objective, easy-to-use, and consistent, which makes it highly suitable for use in glaucoma research and for day-to-day clinical practice.