Rates of Glaucomatous Structural and Functional Change From a Large Clinical Population: The Duke Glaucoma Registry Study

The Impact of Achieving Target Intraocular Pressure on Glaucomatous Retinal Nerve Fiber Layer Thinning in a Treated Clinical Population

PURPOSE

To estimate the effect of being below and above the clinician-set target intraocular pressure (IOP) on rates of glaucomatous retinal nerve fiber layer (RNFL) thinning in a treated real-world clinical population.

DESIGN

Retrospective cohort study.

METHODS

A total of 3256 eyes (1923 patients) with ≥5 reliable optical coherence tomography scans and 1 baseline visual field test were included. Linear mixed-effects modeling estimated the effects of the primary independent variables (mean target difference [measured IOP - target IOP] and mean IOP, mm Hg) on the primary dependent variable (RNFL slope, µm/y) while accounting for additional confounding variables (age, biological sex, race, baseline RNFL, baseline pachymetry, and disease severity). A spline term accounted for differential effects when above (target difference >0 mm Hg) and below (target difference ≤0 mm Hg) target pressure.

RESULTS

Eyes below and above target had significantly different mean RNFL slopes (-0.44 vs -0.71 µm/y, P < .001). Each 1 mm Hg increase above target had a 0.143 µm/y faster rate of RNFL thinning (P < .001). Separating by disease severity, suspect, mild, moderate, and advanced glaucoma had 0.135 (P = .002), 0.116 (P = .009), 0.203 (P = .02), and 0.65 (P = .22) µm/y faster rates of RNFL thinning per 1 mm Hg increase, respectively.

CONCLUSIONS

Being above the clinician-set target pressure is associated with more rapid RNFL thinning in suspect, mild, and moderate glaucoma. Faster rates of thinning were also present in advanced glaucoma, but statistical significance was limited by the lower sample size of eyes above target and the optical coherence tomography floor effect.

Short-term Detection of Fast Progressors in Glaucoma: The Fast Progression Assessment through Clustered Evaluation (Fast-PACE) Study

PURPOSE

To evaluate the performance of an intensive, clustered testing approach in identifying eyes with rapid glaucoma progression over 6 months in the Fast Progression Assessment through Clustered Evaluation (Fast-PACE) Study.

DESIGN

Prospective cohort study.

PARTICIPANTS

A total of 125 eyes from 65 primary open-angle glaucoma (POAG) subjects.

METHODS

Subjects underwent 2 sets of 5 weekly visits (clusters) separated by an average of 6 months and then were followed with single visits every 6 months for an overall mean follow-up of 25 months (mean of 17 tests). Each visit consisted of testing with standard automated perimetry (SAP) 24-2 and 10-2, and spectral-domain OCT (SD-OCT). Progression was assessed using trend analyses of SAP mean deviation (MD) and retinal nerve fiber layer (RNFL) thickness. Generalized estimating equations were applied to adjust for correlations between eyes for confidence interval (CI) estimation and hypothesis testing.

MAIN OUTCOME MEASURES

Diagnostic accuracy of the 6-month clustering period to identify progression detected during the overall follow-up.

RESULTS

A total of 19 of 125 eyes (15%, CI, 9%-24%) progressed based on SAP 24-2 MD over the 6-month clustering period. A total of 14 eyes (11%, CI, 6%-20%) progressed on SAP 10-2 MD, and 16 eyes (13%, CI, 8%-21%) progressed by RNFL thickness, with 30 of 125 eyes (24%, CI, 16%-34%) progressing by function, structure, or both. Of the 35 eyes progressing during the overall follow-up, 25 had progressed during the 6-month clustering period, for a sensitivity of 71% (CI, 53%-85%). Of the 90 eyes that did not progress during the overall follow-up, 85 also did not progress during the 6-month period, for a specificity of 94% (CI, 88%-98%). Of the 14 eyes considered fast progressors by SAP 24-2, SAP 10-2, or SD-OCT during the overall follow-up, 13 were identified as progressing during the 6-month cluster period, for a sensitivity of 93% (CI, 66%-100%) for identifying fast progression with a specificity of 85% (CI, 77%-90%).

CONCLUSIONS

Clustered testing in the Fast-PACE Study detected fast-progressing glaucoma eyes over 6 months. The methodology could be applied in clinical trials investigating interventions to slow glaucoma progression and may be of value for short-term assessment of high-risk subjects.

FINANCIAL DISCLOSURE(S)

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

Racial-ethnic disparities in concurrent rates of peripapillary & macular OCT parameters among a large glaucomatous clinical population

OBJECTIVES

To compare rates of change in peripapillary retinal nerve fibre layer (pRNFL) and macular ganglion cell-inner plexiform layer (mGCIPL) parameters among different race-ethnicities from a large electronic health record database of subjects with or suspected of glaucoma.

METHODS

In this retrospective cohort study, rates of change were obtained using joint longitudinal linear mixed models for eyes with ≥3 visits and ≥1 year of follow-up, adjusting for age, sex, intraocular pressure, central corneal thickness, and baseline pRNFL and mGCIPL thickness. Best linear unbiased predictor estimates of various parameters were stratified by baseline glaucoma severity and analysed by racial-ethnic group.

RESULTS

A total of 21,472 spectral domain optical coherence tomography (OCT) pRNFL scans and 14,431 mGCIPL scans from 2002 eyes were evaluated. A total of 200 (15.6%) and 601 (46.8%) subjects identified as non-Hispanic Black (NHB) and Hispanic, respectively. NHB eyes exhibited faster rates of change in pRNFL among glaucoma suspect (global pRNFL -0.57 ± 0.55 µm/year vs. -0.37 ± 0.62 µm/year among Hispanics, p < 0.001), mild glaucoma (superior pRNFL quadrant -1.20 ± 1.06 µm/year vs. -0.75 ± 1.51 µm/year among non-Hispanic Whites (NHW), p = 0.043), and moderate glaucoma eyes (superior pRNFL quadrant -1.31 ± 1.49 µm/year vs. -0.52 ± 1.26 µm/year among Hispanics, p = 0.003). NHB eyes exhibited faster rates of mGCIPL loss corresponding to pRNFL rates. Global pRNFL and mGCIPL rates were strongly correlated (R2 = 0.70).

CONCLUSIONS

Adjusted rates of pRNFL and mGCIPL loss significantly differed between racial-ethnic groups when stratified by glaucoma severity, with faster rates among NHB patients. These differences highlight key racial-ethnic disparities in adjusted rates of glaucoma OCT parameters.

Performance of Linear Mixed Models in Estimating Structural Rates of Glaucoma Progression Using Varied Random Effect Distributions

Purpose

To compare how linear mixed models (LMMs) using Gaussian, Student t, and log-gamma (LG) random effect distributions estimate rates of structural loss in a glaucomatous population using OCT and to compare model performance to ordinary least squares (OLS) regression.

Design

Retrospective cohort study.

Subjects

Patients in the Bascom Palmer Glaucoma Repository (BPGR).

Methods

Eyes with ≥ 5 reliable peripapillary retinal nerve fiber layer (RNFL) OCT tests over ≥ 2 years were identified from the BPGR. Retinal nerve fiber layer thickness values from each reliable test (signal strength ≥ 7/10) and associated time points were collected. Data were modeled using OLS regression as well as LMMs using different random effect distributions. Predictive modeling involved constructing LMMs with (n - 1) tests to predict the RNFL thickness of subsequent tests. A total of 1200 simulated eyes of different baseline RNFL thickness values and progression rates were developed to evaluate the likelihood of declared progression and predicted rates.

Main Outcome Measures

Model fit assessed by Watanabe-Akaike information criterion (WAIC) and mean absolute error (MAE) when predicting future RNFL thickness values; log-rank test and median time to progression with simulated eyes.

Results

A total of 35 862 OCT scans from 5766 eyes of 3491 subjects were included. The mean follow-up period was 7.0 ± 2.3 years, with an average of 6.2 ± 1.4 tests per eye. The Student t model produced the lowest WAIC. In predictive models, all LMMs demonstrated a significant reduction in MAE when estimating future RNFL thickness values compared with OLS (P < 0.001). Gaussian and Student t models were similar and significantly better than the LG model in estimating future RNFL thickness values (P < 0.001). Simulated eyes confirmed LMM performance in declaring progression sooner than OLS regression among moderate and fast progressors (P < 0.01).

Conclusions

LMMs outperformed conventional approaches for estimating rates of OCT RNFL thickness loss in a glaucomatous population. The Student t model provides the best model fit for estimating rates of change in RNFL thickness, although the use of the Gaussian or Student t distribution in models led to similar improvements in accurately estimating RNFL loss.

Financial Disclosures

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

Detecting Fast Progressors: Comparing a Bayesian Longitudinal Model to Linear Regression for Detecting Structural Changes in Glaucoma

PURPOSE

Demonstrate that a novel Bayesian hierarchical spatial longitudinal (HSL) model identifies macular superpixels with rapidly deteriorating ganglion cell complex (GCC) thickness more efficiently than simple linear regression (SLR).

DESIGN

Prospective cohort study.

SETTING

Tertiary Glaucoma Center.

SUBJECTS

One hundred eleven eyes (111 patients) with moderate to severe glaucoma at baseline and ≥4 macular optical coherence tomography scans and ≥2 years of follow-up.

OBSERVATION PROCEDURE

Superpixel-patient-specific GCC slopes and their posterior variances in 49 superpixels were derived from our latest Bayesian HSL model and Bayesian SLR. A simulation cohort was created with known intercepts, slopes, and residual variances in individual superpixels.

MAIN OUTCOME MEASURES

We compared HSL and SLR in the fastest progressing deciles on (1) proportion of superpixels identified as significantly progressing in the simulation study and compared to SLR slopes in cohort data; (2) root mean square error (RMSE), and SLR/HSL RMSE ratios.

RESULTS

Cohort- In the fastest decile of slopes per SLR, 77% and 80% of superpixels progressed significantly according to SLR and HSL, respectively. The SLR/HSL posterior SD ratio had a median of 1.83, with 90% of ratios favoring HSL. Simulation- HSL identified 89% significant negative slopes in the fastest progressing decile vs 64% for SLR. SLR/HSL RMSE ratio was 1.36 for the fastest decile of slopes, with 83% of RMSE ratios favoring HSL.

CONCLUSION

The Bayesian HSL model improves the estimation efficiency of local GCC rates of change regardless of underlying true rates of change, particularly in fast progressors.

Social history and glaucoma progression: the effect of body mass index, tobacco and alcohol consumption on the rates of structural change in patients with glaucoma

BACKGROUND/AIMS

Although obesity, tobacco and alcohol consumption were linked to the progression of numerous chronic diseases, an association of these social history aspects with glaucoma progression is not yet determined. This study aims to investigate the effect of body mass index (BMI) and history of tobacco and alcohol use on the rates of retinal nerve fibre layer (RNFL) change over time in glaucoma patients.

METHODS

2839 eyes of 1584 patients with glaucoma from the Duke Ophthalmic Registry were included. Patients had at least two spectral-domain optical coherency tomography (SD-OCT) tests over a minimum 6-month follow-up. Self-reported history of alcohol and tobacco consumption was extracted from electronic health records and mean BMI was calculated. Univariable and multivariable linear mixed models were used to determine the effect of each parameter on RNFL change over time.

RESULTS

Mean follow-up time was 4.7±2.1 years, with 5.1±2.2 SD-OCT tests per eye. 43% and 54% of eyes had tobacco or alcohol consumption history, respectively, and 34% were classified as obese. Higher BMI had a protective effect on glaucoma progression (0.014 µm/year slower per each 1 kg/m2 higher; p=0.011). Tobacco and alcohol consumption were not significantly associated with RNFL change rates (p=0.473 and p=0.471, respectively). Underweight subjects presented significantly faster rates of structural loss (-0.768 µm/year; p=0.002) compared with normal weight.

CONCLUSIONS

In a large clinical population with glaucoma, habits of tobacco and alcohol consumption showed no significant effect on the rates of RNFL change. Higher BMI was significantly associated with slower rates of RNFL loss.

Visual Field Outcomes in the Primary Tube Versus Trabeculectomy Study

PURPOSE

To describe visual field outcomes in the Primary Tube Versus Trabeculectomy (PTVT) Study.

DESIGN

Cohort analysis of a prospective multicenter randomized clinical trial.

SUBJECTS

A total of 155 eyes from 155 subjects randomly assigned to treatment with tube shunt surgery (n=84) or trabeculectomy with mitomycin C (n=71).

METHODS

The PTVT Study was a multicenter randomized clinical trial comparing the safety and efficacy of trabeculectomy and tube shunt surgery in eyes without prior intraocular surgery. Subjects underwent standard automated perimetry (SAP) at baseline and annually for five years. SAP tests were deemed reliable if the false positive rate was ≤15%. Tests were excluded if visual acuity was ≤20/400 or loss of ≥2 Snellen lines from baseline were attributed to a non-glaucomatous etiology. Linear mixed-effects models were used to compare rates of change in SAP mean deviation (MD) between the two treatment groups. Intraocular pressure (IOP) control was assessed by percentage of visits with IOP <18 mmHg and mean IOP.

OUTCOME MEASURES

Rate of change in SAP MD during follow-up.

RESULTS

A total of 730 SAP tests were evaluated, with an average of 4.7 tests per eye. The average SAP MD at baseline was -12.8±8.3 dB in the tube group and -12.0±8.4 dB in the trabeculectomy group (p=0.57). The mean rate of change in SAP MD was -0.32±0.39 dB/year in the trabeculectomy group and -0.47±0.43 dB/year in the tube group (p=0.23). Eyes with mean IOP 14-17.5 mmHg had significantly faster rates of SAP MD loss compared to eyes with mean IOP <14 mmHg (-0.59±0.13 vs. -0.27±0.08 dB/year, p=0.012) and eyes with only 50-75% of visits with IOP <18 mmHg had faster rates than those with 100% of visits with IOP <18 mmHg (-0.90±0.16 vs. -0.29±0.08 dB/year, p<0.001). Multivariable analysis identified older age and worse IOP control as risk factors for faster progression in both treatment groups.

CONCLUSIONS

No statistically significant difference in mean rates of visual field change was observed between trabeculectomy and tube shunt surgery in the PTVT Study. Worse IOP control was significantly associated with faster rates of SAP MD loss during follow-up. Older patients were also at risk for faster progression.

Longitudinal Rates of Change in Structural Parameters of Optical Coherence Tomography in Primary Angle Closure Glaucoma following Laser Iridotomy along with Peripheral Iridoplasty

Background

This study aimed to investigate longitudinal rates of change (LRCs) of structural parameters from optical coherence tomography (OCT) in patients with primary angle closure glaucoma (PACG) after laser iridotomy (LI) along with laser peripheral iridoplasty (PI).

Methods

Among 146 patients diagnosed with PACG, thirty-two subjects (32 eyes) who underwent LI plus PI and accomplished more than five times of reliable OCT tests were included in the current retrospective study. Retinal nerve fiber layer (RNFL) and Bruch's membrane opening-minimum rim width (BMO-MRW) were measured by spectral-domain OCT with three month interval. LRCs of global and six Garway-Heath sectors were investigated using the linear mixed-effects model which adjusted BMO area, sex, and age. Imaging of dual Scheimpflug analyzer was performed before and at 1 week after LI with PI and yearly thereafter.

Results

The mean follow-up period was 32.28 ± 13.34 months with a mean number of 10.18 ± 3.33 OCT images. Baseline characteristics are as follows: age, 63 ± 7.9 years; female, 62.5%; intraocular pressure(IOP), 15.48 ± 4.79 mmHg; anterior chamber depth, 2.09 ± 0.18 mm; and mean deviation, -7.97 ± 8.48 dB. Global LRC of BMO-MRW was 0.86 ± 1.34 μm/yr and RNFL was -0.64 ± 0.22 μm/yr. IOP decreased significantly to 13.06 ± 2.21 mmHg (p=0.001) while anterior chamber volume (p=0.011) and mean anterior chamber angle (p=0.022) increased significantly after LI along with PI compared to the baseline at the final visit.

Conclusions

LRC of a new parameter, BMO-MRW, and LRC of RNFL were relatively low in patients with PACG, following LI along with PI. After widening of the anterior chamber angle and decrease of IOP due to LI plus PI, PACG might show stable structural prognosis assessed by OCT.

Intraocular pressure reduction and progression of highly myopic glaucoma: a 12-year follow-up cohort study

AIMS

To investigate any association between intraocular pressure (IOP) reduction amount and open-angle glaucoma (OAG) progression in highly myopic eyes and to determine the associated risk factors.

METHODS

One hundred and thirty-one (131) eyes of 131 patients with highly myopic OAG, all of whom had received topical medications and been followed for 5 years or longer, were enrolled. Based on the IOP reduction percentage, patients were categorised into tertile groups, and subsequently, the upper-tertile and lower-tertile groups were compared for the cumulative probability of glaucoma progression. Kaplan-Meier survival analysis and log-rank testing were applied in the comparison, and multivariate analysis with Cox's proportional hazard model, additionally, was performed to identify progression risk factors.

RESULTS

Throughout the average 11.6±4.4 year follow-up on the 131 eyes (mean age, 41.2 years at initial visit; baseline IOP, 16.4 mm Hg), 72 eyes (55.0%) showed glaucoma progression. The upper-tertile group (IOP reduction percentage>23.7%) showed a high cumulative probability of non-progression relative to the lower-tertile group (IOP reduction percentage<11.0%; p=0.034), according to the Kaplan-Meier analysis. Presence of disc haemorrhage (DH; HR=2.189; p=0.032) was determined by the multivariate Cox's proportional hazard model to be significantly associated with glaucoma progression. For progressors, the average rate of retinal nerve fibre layer thickness thinning was -0.88±0.74 µm/year, while the MD change was -0.42±0.36 dB/year.

CONCLUSIONS

Glaucoma progression is associated with amount of IOP reduction by topical medications in highly myopic eyes, and DH occurrence is a glaucoma progression risk factor.

Effect of 24-h blood pressure dysregulations and reduced ocular perfusion pressure in open-angle glaucoma progression

BACKGROUND

Low ocular perfusion pressure (OPP), which depends on the mean arterial pressure (MAP) and intraocular pressure (IOP), is associated with glaucoma. We studied 24-h MAP dysregulations and OPP in relation to the progression of glaucoma damage.

METHODS

We retrospectively analyzed 155 normal-tension glaucoma (NTG) and 110 primary open-angle glaucoma (POAG) patients aged 18 years old followed at the University Hospital Leuven with repeated visual field tests ( n  = 7000 measures, including both eyes) who underwent 24-h ambulatory blood pressure monitoring. Twenty-four-hour MAP dysregulations were variability independent of the mean (VIM), and the five lowest dips in MAP readings over 24 h. OPP was the difference between 2/3 of the MAP and IOP. Glaucoma progression was the deterioration of the visual field, expressed as decibel (dB) changes in mean deviation analyzed by applying multivariable linear mixed regression models.

RESULTS

The mean age was 68 years (53% were women). High 24-h VIMmap was associated with glaucoma progression in POAG ( P  < 0.001) independently of the 24-h MAP level. The estimated changes in mean deviation in relation to dip MAP measures ranged from -2.84 dB [95% confidence interval (CI) -4.12 to -1.57] to -2.16 dB (95% CI -3.46 to -0.85) in POAG. Reduced OPP along with high variability and dips in MAP resulted in worse mean deviation deterioration.

CONCLUSION

The progression of glaucoma damage associates with repetitive and extreme dips in MAP caused by high variability in MAP throughout 24 h. This progression exacerbates if 24-h MAP dysregulations occur along with reduced OPP.

Smoking and progressive retinal nerve fibre layer thinning in glaucoma

BACKGROUND/AIMS

To investigate the relationship between smoking and smoking intensity, and the rate of retinal nerve fibre layer (RNFL) thinning in patients with primary open angle glaucoma (POAG).

METHODS

In this longitudinal study, patients with POAG who had at least 3 years of follow-up with a minimum of 5 visits of optical coherence tomography (OCT) were enrolled. The smoking intensity was calculated as the pack-year at the baseline OCT. Univariable and multivariable linear mixed models were used to determine the effect of each parameter on the rates of RNFL thinning over time. Non-linear least-squares estimation with piecewise regression model was used to investigate the cut-off point for the relationship between circumpapillary RNFL thinning and smoking intensity.

RESULTS

A total of 466 eyes of 314 patients were included over the mean (95% CI) follow-up of 6.6 (6.4 to 6.7) years. Of the 314 patients, 121 (39%) had reported any history of smoking. Greater smoking intensity was associated with faster RNFL thinning (-0.06 (95% CI -0.11 to 0.00) µm/year per 10 pack-year higher; p=0.031) after adjusted for confounding factors. RNFL thinning became significantly faster when smoking intensity was >8 pack-year.

CONCLUSIONS

Smoking intensity is associated with faster rates of RNFL thinning. Evaluation of smoking intensity might add information to the assessment of risk of glaucoma progression. Future studies are required to explore if withdrawing smoking as a modifiable risk factor can decrease progression in patients with glaucoma.

Improved Prediction of Perimetric Loss in Glaucomatous Eyes Using Latent Class Mixed Modeling

PURPOSE

To evaluate whether the identification of distinct classes within a population of glaucoma patients improves estimates of future perimetric loss.

DESIGN

Longitudinal cohort study.

PARTICIPANTS

A total of 6558 eyes of 3981 subjects from the Duke Ophthalmic Registry with ≥ 5 reliable standard automated perimetry (SAP) tests and ≥ 2 years of follow-up.

METHODS

Standard automated perimetry mean deviation (MD) values were extracted with associated timepoints. Latent class mixed models (LCMMs) were used to identify distinct subgroups (classes) of eyes according to rates of perimetric change over time. Rates for individual eyes were then estimated by considering both individual eye data and the most probable class membership for that eye. Data were split into training (80%) and test sets (20%), and test set mean squared prediction errors (MSPEs) were estimated using LCMM and ordinary least squares (OLS) regression.

MAIN OUTCOME MEASURES

Rates of change in SAP MD in each class and MSPE.

RESULTS

The dataset contained 52 900 SAP tests with an average of 8.1 ± 3.7 tests per eye. The best-fitting LCMM contained 5 classes with rates of -0.06, -0.21, -0.87, -2.15, and +1.28dB/year (80.0%, 10.2%, 7.5%, 1.3%, and 1.0% of the population, respectively) labeled as slow, moderate, fast, catastrophic progressors, and "improvers" respectively. Fast and catastrophic progressors were older (64.1 ± 13.7 and 63.5 ± 16.9 vs. 57.8 ± 15.8, P < 0.001) and had generally mild-moderate disease at baseline (65.7% and 71% vs. 52%, P < 0.001) than slow progressors. The MSPE was significantly lower for LCMM compared to OLS, regardless of the number of tests used to obtain the rate of change (5.1 ± 0.6 vs. 60.2 ± 37.9, 4.9 ± 0.5 vs. 13.4 ± 3.2, 5.6 ± 0.8 vs. 8.1 ± 1.1, 3.4 ± 0.3 vs. 5.5 ± 1.1 when predicting the fourth, fifth, sixth, and seventh visual fields (VFs) respectively; P < 0.001 for all comparisons). MSPE of fast and catastrophic progressors was significantly lower with LCMM versus OLS (17.7 ± 6.9 vs. 48.1 ± 19.7, 27.1 ± 8.4 vs. 81.3 ± 27.1, 49.0 ± 14.7 vs. 183.9 ± 55.2, 46.6 ± 16.0 vs. 232.4 ± 78.0 when predicting the fourth, fifth, sixth, and seventh VFs respectively; P < 0.001 for all comparisons).

CONCLUSIONS

Latent class mixed model successfully identified distinct classes of progressors within a large glaucoma population that seemed to reflect subgroups observed in clinical practice. Latent class mixed models were superior to OLS regression in predicting future VF observations.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosuremay be found after the references.

Validating Trend-Based End Points for Neuroprotection Trials in Glaucoma

Purpose

The purpose of this study was to evaluate the power of trend-based visual field (VF) progression end points against long-term development of event-based end points accepted by the US Food and Drug Administration (FDA).

Methods

One eye from 3352 patients with ≥10 24-2 VFs (median = 11 years) follow-up were analyzed. Two FDA-compatible criteria were applied to these series to label "true-progressed" eyes: ≥5 locations changing from baseline by more than 7 dB (FDA-7) or by more than the expected test-retest variability (GPA-like) in 2 consecutive tests. Observed rates of progression (RoP) were used to simulate trial-like series (2 years) randomly assigned (1000 times) to a "placebo" or a "treatment" arm. We simulated neuroprotective "treatment" effects by changing the proportion of "true progressed" eyes in the two arms. Two trend-based methods for mean deviation (MD) were assessed: (1) linear mixed model (LMM), testing average difference in RoP between the two arms, and (2) time-to-progression (TTP), calculated by linear regression as time needed for MD to decline by predefined cutoffs from baseline. Power curves with 95% confidence intervals were calculated for trend and event-based methods on the simulated series.

Results

The FDA-7 and GPA-like progression was achieved by 45% and 55% of the eyes in the clinical database. LMM and TTP had similar power, significantly superior to the event-based methods, none of which reached 80% power. All methods had a 5% false-positive rate.

Conclusions

The trend-based methods can efficiently detect treatment effects defined by long-term FDA-compatible progression.

Translational Relevance

The assessment of the power of trend-based methods to detect clinically relevant progression end points.

Intraocular Pressure and Rates of Macular Thinning in Glaucoma

PURPOSE

To evaluate the effect of intraocular pressure (IOP) on the rates of macular thickness (ganglion cell layer [GCL] and ganglion cell-inner plexiform layer [GCIPL]) change over time measured by spectral-domain (SD) OCT.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Overall, 451 eyes of 256 patients with primary open-angle glaucoma.

METHODS

Data were extracted from the Duke Ophthalmic Registry, a database of electronic medical records of patients observed under routine clinical care at the Duke Eye Center, and satellite clinics. All records from patients with a minimum of 6 months of follow-up and at least 2 good-quality Spectralis SD-OCT macula scans were included. Linear mixed models were used to investigate the relationship between average IOP during follow-up and rates of GCL and GCIPL thickness change over time.

MAIN OUTCOME MEASURES

The effect of IOP on the rates of GCL and GCIPL thickness loss measured by SD-OCT.

RESULTS

Eyes had a mean follow-up of 1.8 ± 1.3 years, ranging from 0.5 to 10.2 years. The average rate of change for GCL thickness was -0.220 μm/year (95% confidence interval [CI], -0.268 to -0.172 μm/year) and for GCIPL thickness was -0.231 μm/year (95% CI, -0.302 to -0.160 μm/year). Each 1-mmHg higher mean IOP during follow-up was associated with an additional loss of -0.021 μm/year of GCL thickness (P = 0.001) and -0.032 μm/year of GCIPL thickness (P = 0.001) after adjusting for potentially confounding factors, such as baseline age, disease severity, sex, race, central corneal thickness, and follow-up time.

CONCLUSIONS

Higher IOP was significantly associated with faster rates of GCL and GCIPL loss over time measured by SD-OCT, even during relatively short follow-up times. These findings support the use of SD-OCT GCL and GCIPL thickness measurements as structural biomarkers for the evaluation of the efficacy of IOP-lowering therapies in slowing down the progression of glaucoma.

FINANCIAL DISCLOSURE(S)

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

Rates of Visual Field Change in Eyes With Optic Disc Drusen

BACKGROUND

Optic disc drusen (ODD) are calcified deposits in the prelaminar portion of the optic nerve head. Although often asymptomatic, these deposits can cause progressive visual field defects and vision loss. The purpose of this study was to evaluate rates of functional loss in eyes with ODD and to investigate risk factors associated with rates of visual field progression.

METHODS

This was a retrospective cohort study including 65 eyes of 43 patients with ODD from the Duke Ophthalmic Registry. All eyes had at least 12 months of follow-up and at least 3 reliable standard automated perimetry (SAP) tests. Linear mixed models were used to estimate rates of SAP mean deviation (MD) loss over time. Univariable and multivariable models were used to assess the effect of clinical variables and intraocular pressure (IOP) on rates of change.

RESULTS

Subjects were followed for an average of 7.6 ± 5.3 years. The mean rate of SAP MD change was -0.23 ± 0.26 dB/year, ranging from -1.19 to 0.13 dB/year. Fifty-seven eyes (87.7%) had slow progression (slower than -0.5 dB/year), 6 eyes (9.2%) had moderate progression (between -0.5 dB/year and -1 dB/year), and 2 eyes (3.1%) had fast progression (faster than -1 dB/year). In multivariable models, older age and worse SAP MD at baseline were significantly associated with faster rates of change. Mean IOP was not associated with faster rates of MD change in both univariable and multivariable analyses.

CONCLUSIONS

Most eyes with ODD had slow rates of visual field loss over time. Age and baseline severity were significantly associated with faster rates of visual field loss.

Association between statin use and rates of structural and functional loss in glaucoma

BACKGROUND/AIMS

To evaluate the association between statin use and rates of standard automated perimetry (SAP) and retinal nerve fibre layer (RNFL) change in patients with glaucoma and glaucoma suspects.

METHODS

This retrospective cohort study included subjects from the Duke Glaucoma Registry with primary open-angle glaucoma and glaucoma suspects. Subjects were assigned to groups according to history of statin use. Rates of change in SAP mean deviation (MD) and spectral-domain optical coherence tomography (SD OCT) RNFL thickness over time were estimated using linear mixed models and compared in the statin versus control groups. The effect of duration of statin use was also assessed. Patients with glaucoma versus suspects were analysed separately. Analyses were adjusted for potential confounding factors of age, gender, race, intraocular pressure and follow-up time.

RESULTS

The study included 10 049 SAP tests and 14 198 SD OCT tests from 3007 eyes (1978 patients) followed for an average of 4.7±2.0 years. Of these, 775 subjects (1179 eyes) had a history of statin use. No difference in rates of change was seen between the statin versus control groups for MD (-0.07±0.16 dB/year vs -0.07±0.15 dB/year; p=0.873, respectively) or RNFL thickness (-0.70±0.60 µm/year vs -0.70±0.61 µm/year; p=0.923, respectively). Multivariable models controlling for potential confounders showed no significant association between duration of statin use and rates of MD or RNFL thickness change.

CONCLUSIONS

We did not find a statistically significant association between statin use or duration of statin use and rates of structural and functional change in those with glaucoma or glaucoma suspects.

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.

Five-Year Visual Field Outcomes of the HORIZON Trial

PURPOSE

To compare visual field (VF) progression between glaucoma patients receiving cataract surgery alone (CS) or with a Hydrus microstent (CS-HMS).

DESIGN

Post hoc analysis of VF data from the HORIZON multicenter randomized controlled trial.

METHODS

A total of 556 patients with glaucoma and cataract were randomized 2:1 to either CS-HMS (369) or CS (187) and followed up for 5 years. VF was performed at 6 months and then every year after surgery. We analyzed data for all participants with at least 3 reliable VFs (false positives < 15%). Average between-group difference in rate of progression (RoP) was tested using a Bayesian mixed model and a 2-sided Bayesian P value <.05 (main outcome). A multivariable model measured the effect of intraocular pressure (IOP). A survival analysis compared the probability of global VF sensitivity dropping by predefined cutoffs (2.5, 3.5, 4.5, and 5.5 dB) from baseline.

RESULTS

Data from 352 eyes in the CS-HMS arm and 165 in the CS arm were analyzed (2966 VFs). The mean RoP was -0.26 dB/y (95% credible interval -0.36, -0.16) for CS-HMS and -0.49 dB/y (95% credible interval -0.63, -0.34) for CS. This difference was significant (P = .0138). The difference in IOP only explained 17% of the effect (P < .0001). Five-year survival analysis showed an increased probability of VF worsening by 5.5 dB (P = .0170), indicating a greater proportion of fast progressors in the CS arm.

CONCLUSIONS

CS-HMS has a significant effect on VF preservation in glaucoma patients compared with CS alone, reducing the proportion of fast progressors.

Identifying Risk Factors for Blindness From Glaucoma at First Presentation to a Tertiary Clinic

PURPOSE

Glaucoma is the leading cause of irreversible blindness, a crippling disability resulting in higher risks of chronic health conditions. To better understand disparities in blindness risk, we identified risk factors of blindness on first presentation to a glaucoma clinic using a large clinical database.

DESIGN

Retrospective cross-sectional study.

METHODS

We used electronic health records of glaucoma patients from the Duke Ophthalmic Registry. International Classification of Diseases codes were used to identify glaucoma and exclude concurrent diseases. Blindness classification was based on the definition of legal blindness. Risk factors included gender, race, marital status, age, intraocular pressure, diabetes history, income level, and education. Odds ratios (ORs) and 95% CIs were calculated for risk factors using univariable and multivariable logistic regression.

RESULTS

Our cohort consisted of 3753 patients, with 192 (5%) blind on first presentation. In univariable models, African American / Black race (OR 2.48, 95% CI 1.83-3.36), single marital status (1.74, 95% CI 1.25-2.44), prior diabetes diagnosis (2.23, 95% CI 1.52-3.27), and higher intraocular pressure (1.29 per 1 SD higher, 95% CI 1.13-1.46) were associated with increased risk of presenting blind, whereas higher annual income (0.75, 95% CI 0.65-0.86) and education (0.77, 95% CI 0.69-0.85) were associated with lower risk. These associations remained significant and in the same direction in a multivariable model apart from income, which became insignificant.

CONCLUSIONS

Using a large real-world clinical database, we identified risk factors associated with presentation with blindness among glaucoma patients. Our results highlight disparities in health care outcomes and indicate the importance of targeted education to reduce disparities in blindness.

Validation of Rates of Mean Deviation Change as Clinically Relevant End Points for Glaucoma Progression

PURPOSE

To investigate whether rates of standard automated perimetry (SAP) mean deviation (MD) over an initial 2-year follow-up period were predictive of events of visual field progression over an extended follow-up.

DESIGN

Longitudinal, prospective, observational study.

PARTICIPANTS

Two hundred forty-six eyes of 168 patients with glaucoma followed up every 6 months for up to 5 years.

METHODS

Patients were required to have a minimum of 5 reliable SAP tests during the first 2 years of follow-up. Events of progression were evaluated using 2 methods: Guided Progression Analysis (GPA; Carl Zeiss Meditec, Inc) and a United States Food and Drug Administration (FDA)-suggested end point. The date of the first test showing progression after the first 2 years was considered to be the event date. Rates of change in SAP MD were calculated for the first 2 years of follow-up, and joint longitudinal survival models were used to assess the risk of faster initial MD loss for subsequent progression based on each event analysis.

MAIN OUTCOME MEASURE

Risk of having an event of progression based on initial rates of SAP MD change.

RESULTS

Fifty-six eye (22.8%) showed an event of progression by the GPA and 51 eyes (20.7%) did so by the FDA end point. Each 0.1-dB/year faster rate of SAP MD loss in the first 2 years was associated with a 26% increase in risk of a GPA progression end point developing (R2 = 76%) and 32% risk of an FDA-based end point developing (R2 = 83%). A reduction of 30% in the rate of MD change in the first 2 years was associated with a 20% reduction in the cumulative probability of a progression event developing over 5 years of follow-up.

CONCLUSIONS

Rates of SAP MD change for eyes with glaucoma calculated over the initial 2 years of follow-up were strongly predictive of events of progression over subsequent follow-up. Our findings give support for the use of slopes of MD change as suitable end points of progression in clinical trials.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Fast Progressors in Glaucoma: Prevalence Based on Global and Central Visual Field Loss

PURPOSE

To determine the prevalence of fast global and central visual field (VF) progression in individuals with glaucoma under routine care.

DESIGN

Observational study.

PARTICIPANTS

Six hundred ninety-three eyes of 461 individuals with glaucoma followed up over a median of 4.5 years.

METHODS

This study included (1) patients at a private ophthalmology clinic in Melbourne, Australia, and (2) individuals in 2 prospective longitudinal observational studies across 3 sites in the United States. All individuals had a diagnosis of glaucoma and were under routine care, and had performed 5 or more reliable 24-2 VF tests over a 1- to 5-year period. Ordinary least squares regression analyses were used to calculate the rate of global mean deviation (MD) change over time and the rate of the mean total deviation values of the 12 test locations within the central 10° region (MTD10) for each eye.

MAIN OUTCOME MEASURES

Prevalence of progression based on the rate of MD and the MTD10 change across various fixed cutoffs and cutoffs based on the estimated normal distribution (from the positive slopes).

RESULTS

Based on the MD and the MTD10, 12.5% and 11.7% of the eyes, respectively, exhibited a rate of change that was less than -1.0 dB/year (being a rate that typically is defined as "fast progression" for MD values), and 29.0% of the eyes showed a change of less than -0.5 dB/year on MTD10. Furthermore, 12.7% and 9.1% of the eyes exhibited a rate of change that exceeded the 1% cutoff of the estimated normal distribution MD and the MTD10 values, respectively.

CONCLUSIONS

This study found that approximately 1 in 8 eyes with glaucoma receiving routine care showed fast progression based on global MD values (< -1.0 dB/year) and that nearly 1 in 3 eyes showed a < -0.5 dB/year decline centrally. These findings highlight the clinical importance of assessing progressive central VF loss and reinforce the need for new therapies to prevent functional disability in a notable proportion of individuals who continue to exhibit fast progression.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Deep Learning-Assisted Detection of Glaucoma Progression in Spectral-Domain OCT

PURPOSE

To develop and validate a deep learning (DL) model for detection of glaucoma progression using spectral-domain (SD)-OCT measurements of retinal nerve fiber layer (RNFL) thickness.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 14 034 SD-OCT scans from 816 eyes from 462 individuals.

METHODS

A DL convolutional neural network was trained to assess SD-OCT RNFL thickness measurements of 2 visits (a baseline and a follow-up visit) along with time between visits to predict the probability of glaucoma progression. The ground truth was defined by consensus from subjective grading by glaucoma specialists. Diagnostic performance was summarized by the area under the receiver operator characteristic curve (AUC), sensitivity, and specificity, and was compared with conventional trend-based analyses of change. Interval likelihood ratios were calculated to determine the impact of DL model results in changing the post-test probability of progression.

MAIN OUTCOME MEASURES

The AUC, sensitivity, and specificity of the DL model.

RESULTS

The DL model had an AUC of 0.938 (95% confidence interval [CI], 0.921-0.955), with sensitivity of 87.3% (95% CI, 83.6%-91.6%) and specificity of 86.4% (95% CI, 79.9%-89.6%). When matched for the same specificity, the DL model significantly outperformed trend-based analyses. Likelihood ratios for the DL model were associated with large changes in the probability of progression in the vast majority of SD-OCT tests.

CONCLUSIONS

A DL model was able to assess the probability of glaucomatous structural progression from SD-OCT RNFL thickness measurements. The model agreed well with expert judgments and outperformed conventional trend-based analyses of change, while also providing indication of the likely locations of change.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Risk factors for structural and functional progression of primary open-angle glaucoma in an African ancestry cohort

BACKGROUND/AIMS

To investigate the rates of structural and functional progression of primary open-angle glaucoma in an African ancestry cohort and identify risk factors for progression.

METHODS

This retrospective study included 1424 eyes from glaucoma cases in the Primary Open-Angle African American Glaucoma Genetics cohort, with ≥2 visits for retinal nerve fibre layer (RNFL) thickness and mean deviation (MD) measurements over ≥6-month follow-up. The rates of structural progression (change in RNFL thickness/year) and functional progression (change in MD/year) were calculated from linear mixed effects models, accounting for intereye correlation and longitudinal correlation. Eyes were categorised as slow, moderate or fast progressors. Risk factors for progression rates were assessed using univariable and multivariable regression models.

RESULTS

The median (interquartile) rates of progression were -1.60 (-2.05 to -1.15) µm/year for RNFL thickness and -0.40 (-0.44 to -0.34) decibels/year for MD. Eyes were categorised as slow (structural: 19%, functional: 88%), moderate (structural: 54%, functional: 11%) and fast (structural: 27%, functional: 1%) progressors. In multivariable analysis, faster RNFL progression was independently associated with thicker baseline RNFL (p<0.0001), lower baseline MD (p=0.003) and beta peripapillary atrophy (p=0.03). Faster MD progression was independently associated with higher baseline MD (p<0.0001), larger cup-to-disc ratios (p=0.02) and lower body mass index (p=0.0004).

CONCLUSION

The median rates of structural and functional progression in this African ancestry cohort were faster than the rates reported from previously published studies in other ethnic groups. Higher baseline RNFL thickness and MD values were associated with faster progression rates. Results highlight the importance of monitoring structural and functional glaucoma progression to provide timely treatment in early disease.

Evidence-Based Guidelines for the Number of Peripapillary OCT Scans Needed to Detect Glaucoma Worsening

PURPOSE

To estimate the number of OCT scans necessary to detect moderate and rapid rates of retinal nerve fiber layer (RNFL) thickness worsening at different levels of accuracy using a large sample of glaucoma and glaucoma-suspect eyes.

DESIGN

Descriptive and simulation study.

PARTICIPANTS

Twelve thousand one hundred fifty eyes from 7392 adult patients with glaucoma or glaucoma-suspect status followed up at the Wilmer Eye Institute from 2013 through 2021. All eyes had at least 5 measurements of RNFL thickness on the Cirrus OCT (Carl Zeiss Meditec) with signal strength of 6 or more.

METHODS

Rates of RNFL worsening for average RNFL thickness and for the 4 quadrants were measured using linear regression. Simulations were used to estimate the accuracy of detecting worsening-defined as the percentage of patients in whom the true rate of RNFL worsening was at or less than different criterion rates of worsening when the OCT-measured rate was also at or less than these criterion rates-for two different measurement strategies: evenly spaced (equal time intervals between measurements) and clustered (approximately half the measurements at each end point of the period).

MAIN OUTCOME MEASURES

The 75th percentile (moderate) and 90th percentile (rapid) rates of RNFL worsening for average RNFL thickness and the accuracy of diagnosing worsening at these moderate and rapid rates.

RESULTS

The 75th and 90th percentile rates of worsening for average RNFL thickness were -1.09 μm/year and -2.35 μm/year, respectively. Simulations showed that, for the average measurement frequency in our sample of approximately 3 OCT scans over a 2-year period, moderate and rapid RNFL worsening were diagnosed accurately only 47% and 40% of the time, respectively. Estimates for the number of OCT scans needed to achieve a range of accuracy levels are provided. For example, 60% accuracy requires 7 measurements to detect both moderate and rapid worsening within a 2-year period if the more efficient clustered measurement strategy is used.

CONCLUSIONS

To diagnose RNFL worsening more accurately, the number of OCT scans must be increased compared with current clinical practice. A clustered measurement strategy reduces the number of scans required compared with evenly spacing measurements.

Baseline 10-2 Visual Field Loss as a Predictor for Future Glaucoma Progression

PRCIS

Presence of baseline 10-2 visual field (VF) loss was the strongest predictor of future rate of 24-2 VF loss and development of new 24-2 progression events, suggesting a role for 10-2 VF testing in baseline glaucoma risk analysis.

PURPOSE

The purpose of this study is to examine the relationship between baseline 10-2 VF loss and future 24-2 VF loss.

MATERIALS AND METHODS

Subjects were participating in a prospective longitudinal study within a VA Medical Center outpatient eye clinic. Eligibility required 2 good quality baseline 10-2 VF tests followed by a minimum of 5 good quality 24-2 VF tests over at least 3 years. Longitudinal 24-2 VF testing was completed every 4-6 months after baseline 10-2 testing. Mixed model regression analyses and Cox Proportional Hazard regression analyses were completed to identify predictors of 24-2 mean deviation change rate and new VF loss events.

RESULTS

We studied 394 eyes of 202 subjects (119 primary open angle glaucoma and 83 glaucoma suspect). Over 6.7 (±1.5) years, 9.9 (±2.3) good quality 24-2 VF tests were completed. In mixed model regression analyses, baseline variables that predicted faster rate of 24-2 VF loss in order of strength of association were presence of baseline 10-2 VF defect, lower 24-2 mean deviation, and higher age. When analyses were completed without 10-2 variables, predictive capability of the model was reduced compared with when 10-2 variables were included. In Cox Proportional Regression analyses evaluating progression events, baseline 10-2 VF defect demonstrated the largest hazard ratio (22 times greater risk for developing future VF loss event in eyes with vs. without baseline 10-2 VF loss).

CONCLUSIONS

Baseline 10-2 VF defect was the most effective predictor of subsequent 24-2 VF progression in this study. These findings imply that presence of baseline 10-2 VF loss may provide unique value for predicting future glaucoma progression.

Association of Intraocular Pressure With Retinal Nerve Fiber Layer Thinning in Patients With Glaucoma

Importance

Higher intraocular pressure variability may be associated with faster structural changes in patients with glaucoma.

Objectives

To investigate the association of mean intraocular pressure and intraocular pressure variability (defined as the SD of intraocular pressure and the intraocular pressure range) with the rate of retinal nerve fiber layer thinning over time in patients with glaucoma.

Design, Setting, and Participants

In this retrospective analysis of a longitudinal cohort, patients were enrolled from the Diagnostic Innovations in Glaucoma Study and the African Descent and Glaucoma Evaluation study. A total of 815 eyes (564 with perimetric glaucoma and 251 with preperimetric glaucoma) from 508 patients with imaging follow-up for a mean of 6.3 years from December 2008 to October 2020 were studied. Data were analyzed from November 2021 to March 2022.

Main Outcomes and Measures

In this longitudinal study, eyes with at least 4 visits and 2 years of follow-up optical coherence tomography and intraocular pressure measurement were included. A linear mixed-effect model was used to investigate the association of intraocular pressure parameters with the rates of retinal nerve fiber layer thinning. Dominance analysis was performed to determine the relative importance of the intraocular pressure parameters.

Results

Of 508 included patients, 280 (55.1%) were female, 195 (38.4%) were African American, 24 (4.7%) were Asian, 281 (55.3%) were White, and 8 (1.6%) were another race or ethnicity; the mean (SD) age was 65.5 (11.0) years. The mean rate of retinal nerve fiber layer change was -0.67 (95% CI, -0.73 to -0.60) μm per year. In multivariable models adjusted for mean intraocular pressure and other confounding factors, faster annual rate of retinal nerve fiber layer thinning was associated with a higher SD of intraocular pressure (-0.20[ 95% CI, -0.26 to -0.15] μm per 1-mm Hg higher; P < .001) or higher intraocular pressure range (-0.05 [95% CI, -0.06 to -0.03] μm per 1-mm Hg higher; P < .001).

Conclusions and Relevance

In this study, intraocular pressure variability was independently associated with structural change in patients with glaucoma, even after adjustment for mean intraocular pressure, supporting its potential value in clinical management.

Nanoparticles for the treatment of glaucoma-associated neuroinflammation

Recently, a considerable amount of literature has emerged around the theme of neuroinflammation linked to neurodegeneration. Glaucoma is a neurodegenerative disease characterized by visual impairment. Understanding the complex neuroinflammatory processes underlying retinal ganglion cell loss has the potential to improve conventional therapeutic approaches in glaucoma. Due to the presence of multiple barriers that a systemically administered drug has to cross to reach the intraocular space, ocular drug delivery has always been a challenge. Nowadays, studies are focused on improving the current therapies for glaucoma by utilizing nanoparticles as the modes of drug transport across the ocular anatomical and physiological barriers. This review offers some important insights on the therapeutic advancements made in this direction, focusing on the use of nanoparticles loaded with anti-inflammatory and neuroprotective agents in the treatment of glaucoma. The prospect of these novel therapies is discussed in relation to the current therapies to alleviate inflammation in glaucoma, which are being reviewed as well, along with the detailed molecular and cellular mechanisms governing the onset and the progression of the disease.

A Framework for Automating Psychiatric Distress Screening in Ophthalmology Clinics Using an EHR-Derived AI Algorithm

Purpose

In patients with ophthalmic disorders, psychosocial risk factors play an important role in morbidity and mortality. Proper and early psychiatric screening can result in prompt intervention and mitigate its impact. Because screening is resource intensive, we developed a framework for automating screening using an electronic health record (EHR)-derived artificial intelligence (AI) algorithm.

Methods

Subjects came from the Duke Ophthalmic Registry, a retrospective EHR database for the Duke Eye Center. Inclusion criteria included at least two encounters and a minimum of 1 year of follow-up. Presence of distress was defined at the encounter level using a computable phenotype. Risk factors included available EHR history. At each encounter, risk factors were used to discriminate psychiatric status. Model performance was evaluated using area under the receiver operating characteristic (ROC) curve and area under the precision-recall curve (PR AUC). Variable importance was presented using odds ratios (ORs).

Results

Our cohort included 358,135 encounters from 40,326 patients with an average of nine encounters per patient over 4 years. The ROC and PR AUC were 0.91 and 0.55, respectively. Of the top 25 predictors, the majority were related to existing distress, but some indicated stressful conditions, including chemotherapy (OR = 1.36), esophageal disorders (OR = 1.31), central pain syndrome (OR = 1.25), and headaches (OR = 1.24).

Conclusions

Psychiatric distress in ophthalmology patients can be monitored passively using an AI algorithm trained on existing EHR data.

Translational Relevance

When paired with an effective referral and treatment program, such algorithms may improve health outcomes in ophthalmology.

Association Between Serum Vitamin D Level and Rates of Structural and Functional Glaucomatous Progression

PRCIS

In a retrospective cohort study, serum vitamin D levels were not associated with rates of structural or functional loss in glaucoma patients, suggesting that low vitamin D level is not a risk factor for progression.

PURPOSE

To investigate the association between serum vitamin D level and rates of functional and structural glaucomatous loss over time.

METHODS

This study included 826 eyes of 536 glaucoma or suspect patients with an average follow-up of 4.8±1.9 years. All patients had at least 1 serum vitamin D measurement, and all eyes had at least 2 reliable standard automated perimetry (SAP) tests and 2 spectral-domain optical coherence tomography (SD OCT) tests with a minimum follow-up of 6 months. Multivariable linear mixed-effects models were used to estimate the association of vitamin D level with rates of change in SAP mean deviation (MD) and OCT retinal nerve fiber layer (RNFL) thickness over time while adjusting for potential confounding factors.

RESULTS

Patients had an average of 3.4±1.7 SAP tests, 4.8±1.9 SD OCT tests, and 2.3±1.9 vitamin D measurements. The average serum vitamin D level was 33.9±13.2 ng/mL. Mean rates of MD and RNFL change were -0.03±0.08 dB/y and -0.68±0.64 µm/y, respectively. After controlling for confounding factors, there was no statistically significant association between mean vitamin D level and rates of MD (β=0.038, 95% CI: -0.006, 0.082, P =0.09) or RNFL loss over time (β=-0.018, 95% CI: -0.092, 0.055, P =0.62).

CONCLUSIONS

We did not find a significant association between vitamin D level and rates of visual field or RNFL loss over time in individuals with glaucoma and glaucoma suspect patients.

Rates of Visual Field Change in Patients With Glaucoma and Healthy Individuals: Findings From a Median 25-Year Follow-up

Importance

Estimating the rate of glaucomatous visual field change provides practical assessment of disease progression and has implications for management decisions.

Objective

To assess the rates of visual field change in patients receiving treatment for glaucoma compared with healthy individuals over an extensive follow-up period and to quantify the impact of important covariates for these rates.

Design, Setting, and Participants

This prospective longitudinal cohort study was conducted in a hospital-based setting from January 1991 to February 2020. The study included 40 patients receiving treatment for open-angle glaucoma and 29 healthy participants. One eye of each participant was randomly selected as the study eye.

Exposures

Patients with glaucoma and healthy participants received testing with standard automated perimetry every 6 months. Individual rates of mean sensitivity change were computed using ordinary least-squares regression analysis, and linear mixed-effects modeling was used to estimate the mean rates of mean sensitivity change in the 2 groups and the impact of baseline mean sensitivity, baseline age, and follow-up intraocular pressure for rate estimates.

Main Outcomes and Measures

Rate of mean sensitivity change in patients with glaucoma and healthy participants.

Results

A total of 40 patients with glaucoma (median age, 53.07 years [IQR, 48.34-57.97 years]; 21 men [52%]) and 29 healthy participants (median age, 48.80 years [IQR, 40.40-59.07 years], 17 women [59%]) were followed up for a median of 25.65 years (IQR, 22.49-27.02 years) and 19.56 years (IQR, 16.19-26.21 years), respectively. Most participants (65 individuals [94%]) self-identified as White, with the exception of 2 patients with glaucoma (1 self-identified as Black and 1 as South Asian) and 2 healthy participants (both self-identified as South Asian). The mean follow-up intraocular pressure of patients with glaucoma (median, 15.83 mm Hg [IQR, 13.05-17.33 mm Hg]) was similar to that of healthy participants (median, 14.94 mm Hg [IQR, 13.28-16.01 mm Hg]; P = .25). In an ordinary least-squares regression analysis, 31 patients (78%) with glaucoma had rates of mean sensitivity change within the range of healthy participants (ie, between -0.20 dB/y and 0.15 dB/y). Linear mixed-effects modeling revealed that the mean (SE) rate of mean sensitivity change in healthy participants was 0.003 (0.033) dB/y (95% CI, -0.062 to 0.068; P = .93). In comparison, patients with glaucoma had a mean (SE) rate of mean sensitivity change that was -0.032 (0.052) dB/y faster, but this difference was not statistically significant (95% CI, -0.134 to 0.070; P = .53). Among covariates, only baseline mean sensitivity was associated with the rate of mean sensitivity change (mean [SE], 0.021 [0.010] dB/y/dB; 95% CI, 0.002-0.041; P = .03).

Conclusions and Relevance

The results of this cohort study suggest that over a median follow-up of more than 25 years, the rate of visual field change in patients receiving treatment for glaucoma was comparable to that of healthy individuals. These findings could guide practitioners in making management decisions.

Ganglion Cell Complex: The Optimal Measure for Detection of Structural Progression in the Macula

PURPOSE

To test the hypothesis that macular ganglion cell complex (GCC) thickness from optical coherence tomography (OCT) provides a stronger change signal regardless of glaucoma severity compared with other macular measures.

DESIGN

Prospective cohort study.

METHODS

Eyes were from 112 patients with moderate to severe glaucoma at baseline from a tertiary glaucoma center. In each 3° × 3° macular superpixel, a hierarchical Bayesian random intercept and slope model with random residual variance was fit to longitudinal full macular thickness (FMT), outer retina layers, GCC, ganglion cell-inner plexiform layer (GCIPL), and ganglion cell layer (GCL) measurements. We estimated population- and individual-level slopes and intercepts. Proportions of substantial worsening and improving superpixel slopes were compared between layers and in superpixels with mild to moderate vs severe damage (total deviation of corresponding visual field location ≥ -8 vs < -8 dB).

RESULTS

Mean (SD) follow-up time and baseline 10-2 visual field mean deviation were 3.6 (0.4) years and -8.9 (5.9) dB, respectively. FMT displayed the highest proportion of significant negative slopes (1932/3519 [54.9%]), followed by GCC (1286/3519 [36.5%]), outer retina layers (1254/3519 [35.6%]), (GCIPL) (1075/3518 [30.6%]), and (GCL) (698/3518 [19.8%]). Inner macular measures detected less worsening in the severe glaucoma group; yet GCC (223/985 [22.6%]) identified the highest proportion (GCIPL: 183/985 [18.6%]; GCL: 106/985 [10.8%]). Proportions of positive rates were small and comparable among all measures.

CONCLUSIONS

GCC is the optimal macular measure for detection of structural change in eyes with moderate to severe glaucoma. Although a higher proportion of worsening superpixels was observed for FMT, a large portion of FMT change could be attributed to changes in outer retina layers.

Rates of Glaucoma Progression Derived from Linear Mixed Models Using Varied Random Effect Distributions

Purpose

To compare the ability of linear mixed models with different random effect distributions to estimate rates of visual field loss in glaucoma patients.

Methods

Eyes with five or more reliable standard automated perimetry (SAP) tests were identified from the Duke Glaucoma Registry. Mean deviation (MD) values from each visual field and associated timepoints were collected. These data were modeled using ordinary least square (OLS) regression and linear mixed models using the Gaussian, Student's t, or log-gamma (LG) distributions as the prior distribution for random effects. Model fit was compared using the Watanabe–Akaike information criterion (WAIC). Simulated eyes of varying initial disease severity and rates of progression were created to assess the accuracy of each model in predicting the rate of change and likelihood of declaring progression.

Results

A total of 52,900 visual fields from 6558 eyes of 3981 subjects were included. Mean follow-up period was 8.7 ± 4.0 years, with an average of 8.1 ± 3.7 visual fields per eye. The LG model produced the lowest WAIC, demonstrating optimal model fit. In simulations, the LG model declared progression earlier than OLS (P < 0.001) and had the greatest accuracy in predicted slopes (P < 0.001). The Gaussian model significantly underestimated rates of progression among fast and catastrophic progressors.

Conclusions

Linear mixed models using the LG distribution outperformed conventional approaches for estimating rates of SAP MD loss in a population with glaucoma.

Translational Relevance

Use of the LG distribution in models estimating rates of change among glaucoma patients may improve their accuracy in rapidly identifying progressors at high risk for vision loss.

Blood Pressure and Glaucomatous Progression in a Large Clinical Population

PURPOSE

To investigate the effect of systemic arterial blood pressure (BP) on rates of progressive structural damage over time in glaucoma.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 7501 eyes of 3976 subjects with glaucoma or suspected of glaucoma followed over time from the Duke Glaucoma Registry.

METHODS

Linear mixed models were used to investigate the effects of BP on the rates of retinal nerve fiber layer (RNFL) loss from spectral-domain OCT (SD-OCT) over time. Models were adjusted for intraocular pressure (IOP), gender, race, diagnosis, central corneal thickness (CCT), follow-up time, and baseline disease severity.

MAIN OUTCOME MEASURE

Effect of mean arterial pressure (MAP), systolic arterial pressure (SAP), and diastolic arterial pressure (DAP) on rates of RNFL loss over time.

RESULTS

A total of 157 291 BP visits, 45 408 IOP visits, and 30 238 SD-OCT visits were included. Mean rate of RNFL change was -0.70 μm/year (95% confidence interval, -0.72 to -0.67 μm/year). In univariable models, MAP, SAP, and DAP during follow-up were not significantly associated with rates of RNFL loss. However, when adjusted for mean IOP during follow-up, each 10 mmHg reduction in mean MAP (-0.06 μm/year; P = 0.007) and mean DAP (-0.08 μm/year; P < 0.001) but not SAP (-0.01 μm/year; P = 0.355) was associated with significantly faster rates of RNFL thickness change over time. The effect of the arterial pressure metrics remained significant after additional adjustment for baseline age, diagnosis, sex, race, follow-up time, disease severity, and corneal thickness.

CONCLUSIONS

When adjusted for IOP, lower MAP and DAP during follow-up were significantly associated with faster rates of RNFL loss, suggesting that levels of systemic BP may be a significant factor in glaucoma progression.

Optical Microangiography and Progressive Retinal Nerve Fiber Layer Loss in Primary Open Angle Glaucoma

PURPOSE

To evaluate the association between optical microangiography (OMAG) measurements and progressive retinal nerve fiber layer (RNFL) loss in primary open angle glaucoma (POAG).

DESIGN

Prospective case series.

METHODS

Sixty-four eyes of 40 patients with POAG (108 quadrants) with mild to moderate functional damage were longitudinally studied for at least 2 years and with a minimum of 3 optical coherence tomography examinations. OMAG imaging was performed at the baseline visit. Effect of clinical parameters (age, sex, presence of systemic diseases, central corneal thickness, presence of disc hemorrhage, and mean and fluctuation of intraocular pressure during follow-up), baseline hemifield mean deviation, baseline quadrant optical coherence tomography RNFL and ganglion cell inner plexiform layer thickness), and OMAG (peripapillary and macular perfusion density [PD] and vessel density [VD]) on the rate of RNFL change was evaluated using linear mixed models.

RESULTS

Average (±SD) mean deviation, RNFL, and ganglion cell inner plexiform layer thickness of the analyzed quadrants at baseline were -5.5 ± 2.9 dB, 96.5 ± 17.9 µm, and 73.8 ± 8.6 µm, respectively. Peripapillary PD and VD in the quadrant were 44.6% ± 5.9% and 17.5 ± 2.2 mm/mm², respectively. Rate of quadrant RNFL change was -1.8 ± 0.6 µm/y. Multivariate mixed models showed that lower peripapillary PD (coefficient = 0.08, P = .01) and lower VD (coefficient = 0.21, P = .02) were significantly associated with a faster rate of RNFL loss.

CONCLUSIONS

Lower baseline peripapillary PD and VD measured using OMAG were significantly associated with a faster rate of RNFL loss in POAG. OMAG imaging provides useful information about the risk of glaucoma progression and the rate of disease worsening.

Cognitive Dysfunctions in Glaucoma: An Overview of Morpho-Functional Mechanisms and the Impact on Higher-Order Visual Function

Background: Glaucoma is a chronic, vision-threatening disease, and a major cause of legal blindness. The current view is no longer limited to the progressive optic nerve injury, since growing evidence strongly support the interpretation of glaucoma as a complex neurodegenerative disease. However, the precise pathogenic mechanisms leading to the onset and progression of central nervous system (CNS) impairment, and the functional consequences of this damage, are still partially understood. The main aim of this review is to provide a complete and updated overview of the current knowledge regarding the CNS involvement in glaucoma, and the possible therapeutic perspectives. Methods: We made a careful survey of the current literature reporting all the relevant findings related to the cognitive dysfunctions occurring in glaucoma, with specific remarks dedicated on the higher-order visual function impairment and the possible employment of neuroprotective agents. Results: The current literature strongly support the interpretation of glaucoma as a multifaceted chronic neurodegenerative disease, widely affecting the CNS. The cognitive impairment may vary in terms of higher-order functions involvement and in the severity of the degeneration. Although several neuroprotective agents are currently available, the development of new molecules represents a major topic of investigation for future clinical trials. Conclusions: Glaucoma earned the right to be fully considered a neurodegenerative disease. Glaucomatous patients may experience a heterogeneous set of visual and cognitive symptoms, progressively deteriorating the quality of life. Neuroprotection is nowadays a necessary therapeutic goal and a future promising way to preserve visual and cognitive functions, thus improving patients' quality of life.

Cost-Effectiveness Analysis of Minimally Invasive Trabecular Meshwork Stents with Phacoemulsification

PURPOSE

To investigate the costs and effects of implanting trabecular meshwork bypass stents during cataract surgery from a societal perspective in the United States.

DESIGN

Cost-utility analysis using Markov models and efficacy/safety data from published pivotal or randomized control trials (RCTs) of devices investigated.

PARTICIPANTS

Patients aged 65 years and older with mild to moderate primary open-angle glaucoma with or without visually significant cataract.

METHODS

With the use of Markov models, glaucoma progression through 4 glaucoma states (mild, moderate, advanced, severe/blind) and death were simulated over 35 years. The cohort with cataract entered the model and received cataract surgery with or without device implantation. We included a medication management only reference group to calculate total costs and outcomes for those without cataract. Intraocular pressure (IOP) reductions from RCTs were converted to glaucoma state transition probabilities using visual field (VF) mean deviation (MD) decline rates from the Early Manifest Glaucoma Trial. Progressive thinning of the retinal nerve fiber layer (RNFL) on OCT imaging related to IOP control warranted further intervention, including adding medication, selective laser trabeculoplasty (SLT), or incisional glaucoma surgery. We estimated whole costs at Medicare rates and obtained utility values for glaucoma states from previous studies. Incremental costs per quality-adjusted life-year (QALY) gained were evaluated at a QALY threshold of $50 000. One-way deterministic sensitivity analysis, scenario analyses, and probabilistic sensitivity analyses addressed parameter uncertainty and demonstrated model robustness.

MAIN OUTCOME MEASURES

Total costs, QALY, and incremental cost-effectiveness ratio (ICER).

RESULTS

Over 35 years in the base case, the Hydrus (Ivantis, Inc.) implanted with cataract surgery arm cost $48 026.13 and gained 12.26 QALYs. The iStent inject (Glaukos Corp.) implanted with cataract surgery arm cost $49 599.86 and gained 12.21 QALYs. Cataract surgery alone cost $54 409.25 and gained 12.04 QALYs. Initial nonsurgical management cost $57 931.22 and gained 11.74 QALY. The device arms dominated or were cost-effective compared with cataract surgery alone within 5 years and throughout sensitivity analyses. The iStent inject arm was cost-effective in 94.19% of iterations in probabilistic sensitivity analyses, whereas the Hydrus arm was cost-effective in 94.69% of iterations.

CONCLUSIONS

Implanting the Hydrus Microstent or iStent inject during cataract surgery is cost-effective at a conservative QALY threshold.

Rapid initial OCT RNFL thinning is predictive of faster visual field loss during extended follow-up in glaucoma

PURPOSE

To investigate the relationship between the rate of retinal nerve fiber layer (RNFL) loss during initial follow-up and the magnitude of associated visual field loss during an extended follow-up period.

DESIGN

Retrospective cohort study.

METHODS

A total of 1,150 eyes of 839 glaucoma patients extracted from the Duke Glaucoma Registry. Rates of RNFL loss were obtained from global RNFL thickness values of the first 5 optical coherence tomography (OCT) scans. Rates of visual field loss were assessed using standard automated perimetry mean deviation (SAP MD) during the entire follow-up period. Joint longitudinal mixed effects models were used to estimate rates of change. Eyes were categorized as fast, moderate or slow progressors based on rates of RNFL loss, with cutoffs of ≤-2 µm/year, -2 to -1 µm/year and ≥-1 µm/year, respectively. Univariable and multivariable regressions were completed to identify significant predictors of SAP MD loss.

RESULTS

The rate of RNFL change was -0.76±0.85 µm/y during initial follow-up, which occurred over 3.7±1.5 years. 765 (66%) eyes were slow, 328 (29%) moderate, and 57 (5%) fast progressors, with rates of RNFL thinning of -0.36±0.54 µm/year, -1.34±0.25 µm/year, and -2.87±1.39 µm/year respectively. The rates of SAP MD loss among slow, moderate, and fast OCT progressors were -0.16±0.35 dB/y, -0.32±0.43 dB/y, and -0.71±0.65 dB/y respectively over the extended follow-up period of 6.1±1.9 years (P<0.001). Age, OCT progressor group, and concurrent SAP rate were all significantly associated with the overall rate of SAP MD loss in a multivariable model (all P<0.001).

CONCLUSION

Rapid RNFL thinning during an initial follow-up period was predictive of concurrent and subsequent rates of visual field decline over an extended period.

Rates of Retinal Nerve Fiber Layer Thinning in Distinct Glaucomatous Optic Disc Phenotypes in Early Glaucoma

PURPOSE

To compare spectral-domain optical coherence tomography (SDOCT) measured circumpapillary retinal nerve fiber layer (cpRNFL) among 4 glaucomatous optic disc phenotypes in early glaucoma.

DESIGN

Clinical cohort study METHODS: In this study, 218 early glaucoma eyes that had at least 3 years of follow-up and a minimum of 4 SDOCT scans were recruited. The optic discs were classified into 4 types based on appearance: 76 generalized cup enlargement (GE), 53 focal ischemic (FI), 22 myopic glaucomatous (MY), and 67 senile sclerotic (SS). A linear mixed effects model was used to compare the rates of global and regional cpRNFL thinning among optic disc phenotypes.

RESULTS

After adjusting for confounders, the SS group (mean [95% CI]: -1.01 [-1.30, -0.73] µm/y) had the fastest mean rate of global cpRNFL thinning followed by FI (-0.77 [-0.97, -0.57] µm/y), MY (0.59 [-0.81, -0.36] µm/y), and GE (-0.58 [-0.75, -0.40] µm/y) at P < .001. The inferior temporal sector had the fastest rate of cpRNFL thinning among the regional measurements except for the MY group (-0.68 [-1.10, -0.26] µm/y, P = .002). In the multivariable analysis, GE (P = .002) and MY (P = .010) phenotypes were associated with significantly slower global rates of cpRNFL thinning compared with the SS phenotype.

CONCLUSIONS

Rates of cpRNFL thinning were different among the 4 glaucomatous optic disc phenotypes. Those patients with early glaucoma with SS phenotype have the fastest cpRNFL thinning. These patients may benefit from more frequent monitoring and the need to advance therapy if cpRNFL thinning is detected.

A New Smartphone-Based Optic Nerve Head Biometric for Verification and Change Detection

Purpose

Lens adapted smartphones are being used regularly instead of ophthalmoscopes. The most common causes of preventable blindness in the world, which are glaucoma and diabetic retinopathy, can develop asymptomatic changes to the optic nerve head (ONH) especially in the developing world where there is a dire shortage of ophthalmologists but ubiquitous mobile phones. We developed a proof-of-concept ONH biometric (application [APP]) to use as a routine biometric on a mobile phone. The unique blood vessel pattern is verified if it maps on to a previously enrolled image.

Methods

The iKey APP platform comprises three deep neural networks (DNNs) developed from anonymous ONH images: the graticule blood vessel (GBV) and the blood vessel specific feature (BVSF) DNNs were trained on unique blood vessel vectors. A non-feature specific (NFS) baseline ResNet50 DNN was trained for comparison.

Results

Verification reached an accuracy of 97.06% with BVSF, 87.24% with GBV and 79.8% using NFS.

Conclusions

A new ONH biometric was developed with a hybrid platform of ONH algorithms for use as a verification biometric on a smartphone. Failure to verify will alert the user to possible changes to the image, so that silent changes may be observed before sight threatening disease progresses. The APP retains a history of all ONH images. Future longitudinal analysis will explore the impact of ONH changes to the iKey biometric platform.

Translational Relevance

Phones with iKey will host ONH images for biometric protection of both health and financial data. The ONH may be used for automatic screening by new disease detection DNNs.

Estimating Ganglion Cell Complex Rates of Change With Bayesian Hierarchical Models

Purpose

Develop a hierarchical longitudinal regression model for estimating local rates of change of macular ganglion cell complex (GCC) measurements with optical coherence tomography (OCT).

Methods

We enrolled 112 eyes with four or more macular OCT images and ≥2 years of follow-up. GCC thickness measurements within central 6 × 6 superpixels were extracted from macular volume scans. We fit data from each superpixel separately with several hierarchical Bayesian random-effects models. Models were compared with the Watanabe–Akaike information criterion. For our preferred model, we estimated population and individual slopes and intercepts (baseline thickness) and their correlation.

Results

Mean (SD) follow-up time and median (interquartile range) baseline 24-2 visual field mean deviation were 3.6 (0.4) years and −6.8 (−12.2 to −4.3) dB, respectively. The random intercepts and slopes model with random residual variance was the preferred model. While more individual and population negative slopes were observed in the paracentral and papillomacular superpixels, superpixels in the superotemporal and inferior regions displayed the highest correlation between baseline thickness and rates of change (r = –0.43 to –0.50 for the top five correlations).

Conclusions

A Bayesian linear hierarchical model with random intercepts/slopes and random variances is an optimal initial model for estimating GCC slopes at population and individual levels. This novel model is an efficient method for estimating macular rates of change and probability of glaucoma progression locally.

Translational Relevance

The proposed Bayesian hierarchical model can be applied to various macular outcomes from different OCT devices and to superpixels of variable sizes to estimate local rates of change and progression probability.

The Effect of Age on Increasing Susceptibility to Retinal Nerve Fiber Layer Loss in Glaucoma

Purpose

To determine whether aging modifies the effect of intraocular pressure (IOP) on progressive glaucomatous retinal nerve fiber layer (RNFL) thinning over time.

Methods

This was a retrospective cohort study involving patients with glaucoma or suspected of having glaucoma who were followed over time from the Duke Glaucoma Registry. Rates of RNFL loss from spectral-domain optical coherence tomography (SD-OCT) were used to assess disease progression. Generalized estimating equations with robust sandwich variance estimators were used to investigate the effects of the interaction of age at baseline and mean IOP on rates of RNFL loss over time. Models were adjusted for gender, race, diagnosis, central corneal thickness, follow-up time, and baseline disease severity.

Results

The study included 85,475 IOP measurements and 60,026 SD-OCT tests of 14,739 eyes of 7814 patients. Eyes had a mean follow-up time of 3.5 ± 1.9 years. The average rate of change in RNFL thickness was –0.70 µm/year (95% confidence interval, –0.72 to –0.67). There was a significant interaction between age and mean IOP and the rate of RNFL loss (P = 0.001), with older eyes having significantly faster rates of RNFL loss than younger ones for the same level of IOP. The effect of IOP on rates of change was greater in the inferior and superior regions of the optic disc.

Conclusions

Age is a significant modifier of the relationship between IOP and glaucomatous loss in RNFL thickness over time. Older patients may be more susceptible to glaucomatous progression than younger patients at the same level of IOP.

Predicting Glaucoma Development With Longitudinal Deep Learning Predictions From Fundus Photographs

PURPOSE

To assess whether longitudinal changes in a deep learning algorithm's predictions of retinal nerve fiber layer (RNFL) thickness based on fundus photographs can predict future development of glaucomatous visual field defects.

DESIGN

Retrospective cohort study.

METHODS

This study included 1,072 eyes of 827 glaucoma-suspect patients with an average follow-up of 5.9 ± 3.8 years. All eyes had normal standard automated perimetry (SAP) at baseline. Additional SAP and fundus photographs were acquired throughout follow-up. Conversion to glaucoma was defined as repeatable glaucomatous defects on SAP. An OCT-trained deep learning algorithm (machine to machine, M2M) was used to predict RNFL thicknesses from fundus photographs. Joint longitudinal survival models were used to assess whether baseline and longitudinal change in M2M's RNFL thickness estimates could predict development of visual field defects.

RESULTS

A total of 196 eyes (18%) converted to glaucoma during follow-up. The mean rate of change in M2M's predicted RNFL thickness was -1.02 μm/y for converters and -0.67 μm/y for non-converters (P < .001). Baseline and rate of change of predicted RNFL thickness were significantly predictive of conversion to glaucoma, with hazard ratios in the multivariable model of 1.56 per 10 μm lower at baseline (95% CI, 1.33-1.82; P < .001) and 1.99 per 1 μm/y faster loss in thickness during follow-up (95% CI, 1.36-2.93; P < .001).

CONCLUSION

Longitudinal changes in a deep learning algorithm's predictions of RNFL thickness measurements based on fundus photographs can be used to predict risk of glaucoma conversion in eyes suspected of having the disease.

Effect of Diabetes Control on Rates of Structural and Functional Loss in Patients with Glaucoma

PURPOSE

To investigate the association between levels of diabetes mellitus (DM) control and rates of visual field and retinal nerve fiber layer (RNFL) loss over time in glaucoma.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 351 eyes of 222 patients with type 2 DM with concomitant primary open-angle glaucoma (POAG) or suspected glaucoma extracted from the Duke Glaucoma Registry.

METHODS

All patients had at least 2 reliable standard automated perimetry (SAP) tests, 2 spectral domain OCT (SD-OCT) tests, and 2 glycated hemoglobin (HbA1c) measures over time with a minimum follow-up of 6 months. Values of HbA1c were summarized for each patient as mean, peak, and fluctuation across time. Multivariable linear mixed models were used to estimate the effect of HbA1c on rates of change in SAP mean deviation (MD) and OCT RNFL thickness loss over time while adjusting for various confounding factors.

MAIN OUTCOME MEASURES

Rates of change in MD and RNFL thickness over time.

RESULTS

Subjects had a mean baseline age of 62.5 ± 10.2 years and follow-up time of 6.9 ± 5.1 years. Subjects had an average of 4.8 SAP tests (range, 2-28), 3.6 SD-OCT tests (range, 2-10), and 8.3 HbA1c tests (range, 2-21). Average HbA1c mean was 7.1% ± 1.1% (range, 5.4-11.7), peak HbA1c over time was 8.1% ± 2% (range, 5.5-15.6), and HbA1c fluctuation was 0.6% ± 0.6% (range, 0-4.4). Mean rate of SAP MD change was -0.09 ± 0.20 decibel/year (median -0.06 decibel/year; interquartile range -0.15 to 0.01 decibel/year), and mean rate of RNFL change was -0.83 ± 0.51 μm/year (median -0.76 μm/year; interquartile range -1.06 to 0.56 μm/year). After adjustment for confounding factors, mean, peak, and fluctuation in HbA1c levels were not significantly associated with rates of MD change over time (P = 0.994, P = 0.689, P = 0.920, respectively), nor were rates of change in RNFL loss over time (P = 0.805, P = 0.575, P = 0.770).

CONCLUSIONS

We did not find a significant association between diabetes control, as measured by levels of HbA1c, and rates of visual field or RNFL loss over time in individuals with glaucoma or suspected glaucoma.

Impact of Intraocular Pressure Control on Rates of Retinal Nerve Fiber Layer Loss in a Large Clinical Population

PURPOSE

To investigate the impact of intraocular pressure (IOP) control on rates of change of spectral-domain OCT (SD-OCT) retinal nerve fiber layer (RNFL) thickness in a large clinical population.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 85 835 IOP measurements and 60 223 SD-OCT tests from 14 790 eyes of 7844 patients.

METHODS

Data were extracted from the Duke Glaucoma Registry, a large database of electronic medical records of patients with glaucoma and suspected disease followed over time at the Duke Eye Center and satellite clinics. All records from patients with a minimum of 6 months of follow-up and at least 2 good-quality SD-OCT scans and 2 clinical visits with Goldmann applanation tonometry were included. Eyes were categorized according to the frequency of visits with IOP below cutoffs of 21 mmHg, 18 mmHg, and 15 mmHg over time. Rates of change for global RNFL thickness were obtained using linear mixed models and classified as slow if change was slower than -1.0 μm/year; moderate if between -1.0 and -2.0 μm/year; and fast if faster than -2.0 μm/year. Multivariable models were adjusted for age, gender, race, diagnosis, central corneal thickness, follow-up time, and baseline disease severity.

MAIN OUTCOME MEASURES

Rates of change in SD-OCT RNFL thickness according to levels of IOP control.

RESULTS

Eyes had a mean follow-up of 3.5±1.9 years. Average rate of change in RNFL thickness was -0.68±0.59 μm/year. Each 1 mmHg higher mean IOP was associated with 0.05 μm/year faster RNFL loss (P < 0.001) after adjustment for potentially confounding variables. For eyes that had fast progression, 41% of them had IOP <21 mmHg in all visits during follow-up, whereas 20% of them had all visits with IOP <18 mmHg, but only 9% of them had all visits with IOP <15 mmHg.

CONCLUSIONS

Intraocular pressure was significantly associated with rates of progressive RNFL loss in a large clinical population. Eyes with stricter IOP control over follow-up visits had a smaller chance of exhibiting fast deterioration. Our findings may assist clinicians in establishing target pressures in clinical practice.