Investigating the usefulness of a cluster-based trend analysis to detect visual field progression in patients with open-angle glaucoma

Long-term prognosis of acute primary angle closure in an east asian cohort

PURPOSE

To provide an updated analysis of the long-term outcomes of patients with acute primary angle closure (APAC) and to investigate the risk factors for visual field (VF) loss progression.

STUDY DESIGN

Retrospective, clinical cohort study METHODS: One hundred and forty-six APAC patients with a minimum of 1-year follow-up were included. The presenting features and the treatment utilized were recorded. The visual and intraocular pressure (IOP) outcomes were analyzed. The main outcome measures were the proportion of blindness and IOP at the final visit. A subset of patients with sufficient VF results was divided into a stable and progressive group based on mean deviation (MD) loss rate. Univariate and multivariate logistic regression analyses were performed to identify predictors of progression.

RESULTS

Nine patients (6.2%) were blind, and 76.0% (111/146) had final decimal visual acuity greater than or equal to 0.5. All patients had normal final IOP, and 65.1% (95/146) were medication-free. 64.4% (94/146) underwent cataract surgery at a median 4 months after their APAC attack. The use of topical hypotensive medications (OR = 8.029, P = 0.012) was the only significant predictor of fast MD loss in the multivariate regression.

CONCLUSIONS

The long-term outcomes of APAC in recent years have been more promising. All patients maintained normal IOP several years following their APAC attack, and fewer than half required hypotensive agents. The incidence of blindness was low. These findings suggest that current practice patterns in the management of APAC are beneficial.

Understanding and identifying visual field progression

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

Utility of targeted mean total deviation trend analysis for detecting progressive visual field changes in early-to-moderate stage glaucoma

OBJECTIVES

To evaluate the clinical utility of trend-based analysis of the targeted mean total deviation (TMTD) by comparing its rates of visual field (VF) change and sensitivities of detecting VF progression with those of the mean total deviation (mTD) in the global and hemifield VF area in early to-moderate glaucoma patients.

METHODS

A single eye from 139 open-angle glaucoma patients with hemifield VF defects and a minimum two year follow-up were retrospectively evaluated. The TMTD was estimated by averaging the total deviation (TD) values after excluding VF points that had a threshold sensitivity of <0 dB in three baseline tests, and the mTD by averaging the entire VF TD values. The study patients were classified as VF progressors vs. non-progressors using both event- and trend-based analysis. The rates of change and ratios of progression detection were compared between TMTD and mTD.

RESULTS

This study included 49 VF progressors and 90 non-progressors. Slopes for the global and VF-affected hemifield TMTD were significantly faster than those for the mTD in each subgroup and in the entire cohort (P < 0.001). Trend-based TMTD analysis detected VF progression in greater proportion than either trend-based mTD or event-based analysis (38.1% vs. 30.2% vs. 27.3%, respectively: VF affected hemifields).

CONCLUSIONS

The rates of change in the TMTD are significantly faster than those for the mTD globally and in the VF-affected hemifields. Trend-based TMTD analysis shows greater sensitivity for detecting VF progression than trend-based mTD or event-based analysis in early-to-moderate glaucoma patients with hemifield VF loss.

Investigating the clinical validity of the guided progression analysis definition with 10-2 visual field in retinitis pigmentosa

PURPOSE

To investigate the clinical validity of the Guided Progression Analysis definition (GPAD) and cluster-based definition (CBD) with the Humphrey Field Analyzer (HFA) 10-2 test in retinitis pigmentosa (RP).

METHODS

Ten non-progressive RP visual fields (VFs) (HFA 10-2 test) were simulated for each of 10 VFs of 111 eyes (10 simulations × 10 VF sequencies × 111 eyes = 111,000 VFs; Dataset 1). Using these simulated VFs, the specificity of GPAD for the detection of progression was determined. Using this dataset, similar analyses were conducted for the CBD, in which the HFA 10-2 test was divided into four quadrants. Subsequently, the Hybrid Definition was designed by combining the GPAD and CBD; various conditions of the GPAD and CBD were altered to approach a specificity of 95.0%. Subsequently, actual HFA 10-2 tests of 116 RP eyes (10 VFs each) were collected (Dataset 2), and true positive rate, true negative rate, false positive rate, and the time required to detect VF progression were evaluated and compared across the GPAD, CBD, and Hybrid Definition.

RESULTS

Specificity values were 95.4% and 98.5% for GPAD and CBD, respectively. There were no significant differences in true positive rate, true negative rate, and false positive rate between the GPAD, CBD, and Hybrid Definition. The GPAD and Hybrid Definition detected progression significantly earlier than the CBD (at 4.5, 5.0, and 4.5 years, respectively).

CONCLUSIONS

The GPAD and the optimized Hybrid Definition exhibited similar ability for the detection of progression, with the specificity reaching 95.4%.

Application of diffusion tensor imaging technology in glaucoma diagnosis

Glaucoma is the first major category of irreversible blinding eye illnesses worldwide. Its leading cause is the death of retinal ganglion cells and their axons, which results in the loss of vision. Research indicates that glaucoma affects the optic nerve and the whole visual pathway. It also reveals that degenerative lesions caused by glaucoma can be found outside the visual pathway. Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique that can investigate the complete visual system, including alterations in the optic nerve, optic chiasm, optic tract, lateral geniculate nuclear, and optic radiation. In order to provide a more solid foundation for the degenerative characteristics of glaucoma, this paper will discuss the standard diagnostic techniques for glaucoma through a review of the literature, describe the use of DTI technology in glaucoma in humans and animal models, and introduce these techniques. With the advancement of DTI technology and its coupling with artificial intelligence, DTI represents a potential future for MRI technology in glaucoma research.

Glaucoma progression. Clinical practice guide

OBJECTIVE

To provide general recommendations that serve as a guide for the evaluation and management of glaucomatous progression in daily clinical practice based on the existing quality of clinical evidence.

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 Reviews) and Cochrane "Risk of bias" tools by at least two reviewers, recommendations were formulated following the Scottish Intercollegiate Guideline network (SIGN) methodology.

RESULTS

Recommendations with their corresponding levels of evidence that may be useful in the interpretation and decision-making related to the different methods for the detection of glaucomatous progression are presented.

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 glaucomatous progression.

[Static automated perimetry in the diagnosis of glaucoma. Assessment of disease progression]

There are several ways to assess glaucoma progression using standard automated perimetry. Most often, ophthalmologists evaluate the stability of visual functions manually when comparing several study protocols. The advantages of clinical assessment are ease of implementation and the ability to interpret data from any device. The main disadvantage of this method is its subjectivity. There are many available automated methods for assessing disease progression involving Humphrey Field Analyzer and Octopus perimeters. Event analysis allows determining glaucoma progression at the time of examination, with consideration of the possible physiological fluctuations in light sensitivity. Trend analysis of perimetric indices makes it possible to assess the rate of glaucoma progression and forecast the trend of changes in visual functions over the next five years. All these methods for assessing progression have certain advantages and disadvantages and cannot be considered ideal. Pointwise and cluster trend analysis are more sensitive in early glaucoma and are being actively researched and developed. These methods have great potential, although they are not yet sufficiently available in clinical practice.

[Optical coherence tomography and optical coherence tomography angiography for detecting glaucoma progression. Part 2. Clinical and functional correlations, monitoring of advanced glaucoma and limitations of the method]

The purpose of this study is to analyze the literature on the role of optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) in the diagnosis of glaucoma. This review considers the structural and functional correlations observed during the progression of glaucomatous optic neuropathy, as well as the capabilities of the method in late glaucoma, describes the strengths and weaknesses of OCT and OCTA, and pays particular attention to the role of OCT in assessing the effectiveness of treatment. Optical coherence tomography is the main method for determining the progression of glaucoma, which plays a key role in the choice of treatment algorithm. However, the use of OCT in far advanced glaucoma has certain particularities and limitations. OCTA can be helpful in overcoming this problem.

Structure-Function Relationship between Cluster Mean Defect and Sector Peripapillary Retinal Nerve Fiber Layer Thickness in Primary Open Angle Glaucoma

Purpose

To determine the structure–function relationship between cluster mean defect (MD) offered by standard automated perimetry and corresponding sector peripapillary retinal nerve fiber layer thickness (pRNFLT) measured with optical coherence tomography (OCT) in primary open angle glaucoma (POAG).

Method

39 healthy eyes (control group), 43 early POAG eyes (global MD ≤ 6 dB, early group), 30 moderate POAG eyes (global MD between 6 and 12 dB, moderate group), and 53 advanced POAG eyes (global MD > 12 dB, advanced group) underwent visual field (VF) examination with Octopus perimeter (dynamic strategy/G2 pattern) and peripapillary retinal nerve fiber layer thickness measurements with RTVue-100 FD-OCT. Spearman analysis was used to investigate the correlation between cluster MDs provided by Octopus perimeter and corresponding sector pRNFLT for the total sample and each subgroup, respectively. Then, linear (y = a+ bx) and curvilinear (quadratic, y = a+bx + cx²) regression analyses were employed to investigate the model for the cluster MD-sector pRNFLT pair with significant correlation. The strength of the relationship was characterized with correlation coefficient (ρ) and coefficient of determination (R²). For the cluster–sector pair that could be fitted by both models, Wilcoxon signed rank test of absolute residuals was used to compare the goodness of fit.

Results

Correlation between cluster MDs and corresponding sector pRNFLT was significant for all clusters in the total sample (ρ values: −0.572 to 0.832, P < 0.001) and in the POAG group (ρ values: −0.551 to −0.777, P < 0.001). The highest ρ values were found for cluster-sector pair 9 and pair 3, respectively. The curvilinear (quadratic) model provided better fit for all 10 cluster-sector pairs in the total sample (R² values: 0.431–0.687, P < 0.001) and in the POAG group (R² values: 0.364–0.594, P < 0.01). The highest R² values were found also for cluster–sector pair 9 and pair 3, respectively. In the control group, no significant correlation was found for any cluster–sector pair (P > 0.01). In the early group, correlation was significant for cluster–sector pairs 3, 8, and 9 (ρ values: −0.449, −0.627, and −0.815, resp., P < 0.01). In the moderate group, correlation was significant for pairs 2, 3, 8, and 9 (ρ values: −0.703, −0.556, −0.680, and −0.637, resp., P < 0.01). In the advanced group, correlation was significant (P < 0.01) for all 10 pairs (ρ values: −0.395 to −0.699, P < 0.001) except for pairs 2, 3, and 8, and the highest ρ value was found for pair 1. For all cluster–sector pairs with significant correlation in the early, moderate, and advanced groups, only linear model could be fitted (P < 0.01), except for pair 9 in the early group and pair 5 in the advanced group.

Conclusions

Cluster MD of the Octopus visual field showed significant moderate-to-strong negative correlation and curvilinear (quadratic) relationship with the corresponding sector pRNFLT for POAG. This type of regional structure–function relationship varied according to the severity of POAG, and at each stage, the significantly correlated cluster–sector pairs mainly showed linear relationship. The results could provide guidance for better utilization of this regional structure–function method in the management of different stages of POAG.

Pointwise and Region-Wise Course of Visual Field Loss in Patients With Glaucoma

Purpose

Accurate assessment of visual field (VF) trend may help clinicians devise the optimum treatment regimen. This study was conducted to investigate the behavior of VF sequences using pointwise and region-wise linear, exponential, and sigmoid regression models.

Materials and Methods

In a retrospective cohort study, 277 eyes of 139 patients with glaucoma who had been followed for at least 7 years were investigated. Linear, exponential, and sigmoid regression models were fitted for each VF test location and Glaucoma Hemifield Test (GHT) region to model the trend of VF loss. The model with the lowest root mean square error (RMSE) was selected as the best fit.

Results

The mean age (standard deviation [SD]) of the patients was 59.9 years (9.8) with a mean follow-up time of 9.3 (0.7) years. The exponential regression had the best fit based on pointwise and region-wise approaches in 39.3% and 38.1% of eyes, respectively. The results showed a better performance based on sigmoid regression in patients with initial VF sensitivity threshold greater than 22 dB (71.6% in pointwise and 62.2% in region-wise approaches). The overall RMSE of the region-wise regression model was lower than the overall RMSE of the pointwise model.

Conclusions

In the current study, nonlinear regression models showed a better fit compared to the linear regression models in tracking VF loss behavior. Moreover, findings suggest region-wise analysis may provide a more appropriate approach for assessing VF deterioration.

Translational Relevance

Findings may confirm a nonlinear progression of VF deterioration in patients with glaucoma.

A Joint Multitask Learning Model for Cross-sectional and Longitudinal Predictions of Visual Field Using OCT

Purpose

We constructed a multitask learning model (latent space linear regression and deep learning [LSLR-DL]) in which the 2 tasks of cross-sectional predictions (using OCT) of visual field (VF; central 10°) and longitudinal progression predictions of VF (30°) were performed jointly via sharing the deep learning (DL) component such that information from both tasks was used in an auxiliary manner (The Association for Computing Machinery's Special Interest Group on Knowledge Discovery and Data Mining [SIGKDD] 2021). The purpose of the current study was to investigate the prediction accuracy preparing an independent validation dataset.

Design

Cohort study.

Participants

Cross-sectional training and testing data sets included the VF (Humphrey Field Analyzer [HFA] 10-2 test) and an OCT measurement (obtained within 6 months) from 591 eyes of 351 healthy people or patients with open-angle glaucoma (OAG) and from 155 eyes of 131 patients with OAG, respectively. Longitudinal training and testing data sets included 7984 VF results (HFA 24-2 test) from 998 eyes of 592 patients with OAG and 1184 VF results (HFA 24-2 test) from 148 eyes of 84 patients with OAG, respectively. Each eye had 8 VF test results (HFA 24-2 test). The OCT sequences within the observation period were used.

Methods

Root mean square error (RMSE) was used to evaluate the accuracy of LSLR-DL for the cross-sectional prediction of VF (HFA 10-2 test). For the longitudinal prediction, the final (eighth) VF test (HFA 24-2 test) was predicted using a shorter VF series and relevant OCT images, and the RMSE was calculated. For comparison, RMSE values were calculated by applying the DL component (cross-sectional prediction) and the ordinary pointwise linear regression (longitudinal prediction).

Main Outcome Measures

Root mean square error in the cross-sectional and longitudinal predictions.

Results

Using LSLR-DL, the mean RMSE in the cross-sectional prediction was 6.4 dB and was between 4.4 dB (VF tests 1 and 2) and 3.7 dB (VF tests 1–7) in the longitudinal prediction, indicating that LSLR-DL significantly outperformed other methods.

Conclusions

The results of this study indicate that LSLR-DL is useful for both the cross-sectional prediction of VF (HFA 10-2 test) and the longitudinal progression prediction of VF (HFA 24-2 test).

The Relationship Between Optic Disc and Retinal Artery Position and Glaucomatous Visual Field Progression

Purpose

To investigate whether retinal structural parameters, including positions of the optic disc and major retinal arteries, affect glaucomatous progression of the visual field (VF).

Methods

In this cohort study, 116 eyes of 73 patients with primary open angle glaucoma (POAG) were included. VFs were measured using the Humphrey Field Analyzer 24-2 program and the VF was divided into seven sectors according to the corresponding optic disc angle. Average total deviation (TD) was calculated in each sector. Positions of major retinal arteries in the superotemporal and inferotemporal areas were decided by identifying the points where the retinal artery intersected the 3.4-mm-diameter circle around the optic disc. The relationship between sectorial TD VF progression rate and eight variables (age, mean and standard deviation of intraocular pressure during the observation period, baseline sectorial TD value, papillomacular bundle tilt angle, and axial length, along with superior/inferior arterial angle) was investigated.

Results

The main outcome measures were the association between retinal structural parameters and glaucomatous progression of VF. The superior retinal artery angular position was positively associated with sectorial TD progression rates in two central sectors in the inferior hemifield, which suggests faster VF progression where superior retinal artery angles are narrow. Papillomacular bundle tilt was not associated with TD progression rate in any sector.

Conclusions

Progression of the inferior VF was associated with the superior retinal artery angular position in this study of POAG.

Development and validation of a visual field cluster in retinitis pigmentosa

The aim was to establish and evaluate a new clustering method for visual field (VF) test points to predict future VF in retinitis pigmentosa. A Humphrey Field Analyzer 10-2 test was clustered using total deviation values from 858 VFs. We stratified 68 test points into 24 sectors. Then, mean absolute error (MAE) of the sector-wise regression with them (S1) was evaluated using 196 eyes with 10 VF sequences and compared to pointwise linear regression (PLR), mean sensitivity of total area (MS) and also another sector-wise regression basing on VF mapping for glaucoma (29 sectors; S2). MAE with S1 were smaller than with PLR when between the first-third and first-seventh VFs were used. MAE with the method were significantly smaller than those of S2 when between the first-sixth and first-ninth VFs were used. The MAE of MS was smaller than those with S1 only when first to 3rd and first to 4th VFs were used; however, the prediction accuracy became far larger than any other methods when larger number of VFs were used. More accurate prediction was achieved using this new sector-wise regression than with PLR. In addition, the obtained cluster was more useful than that for glaucoma to predict progression.

Investigating the clinical usefulness of definitions of progression with 10-2 visual field

BACKGROUND/AIM

To investigate the clinical validity of the Guided Progression Analysis definition (GPAD) and cluster-based definition (CBD) with the Humphrey Field Analyzer 10-2 test in diagnosing glaucomatous visual field (VF) progression, and to introduce a novel definition with optimised specificity by combining the 'any-location' and 'cluster-based' approaches (hybrid definition).

METHODS

64 400 stable glaucomatous VFs were simulated from 664 pairs of 10-2 tests (10 sets × 10 VF series × 664 eyes; data set 1). Using these simulated VFs, the specificity to detect progression and the effects of changing the parameters (number of test locations or consecutive VF tests, and percentile cut-off values) were investigated. The hybrid definition was designed as the combination where the specificity was closest to 95.0%. Subsequently, another 5000 actual glaucomatous 10-2 tests from 500 eyes (10 VFs each) were collected (data set 2), and their accuracy (sensitivity, specificity and false positive rate) and the time needed to detect VF progression were evaluated.

RESULTS

The specificity values calculated using data set 1 with GPAD and CBD were 99.6% and 99.8%. Using data set 2, the hybrid definition had a higher sensitivity than GPAD and CBD, without detriment to the specificity or false positive rate. The hybrid definition also detected progression significantly earlier than GPAD and CBD (at 3.1 years vs 4.2 years and 4.1 years, respectively).

CONCLUSIONS

GPAD and CBD had specificities of 99.6% and 99.8%, respectively. A novel hybrid definition (with a specificity of 95.5%) had higher sensitivity and enabled earlier detection of progression.

Functional assessment of glaucoma: Uncovering progression

Clinicians who manage glaucoma patients carefully monitor the visual field to determine if treatments are effective or interventions are needed. Visual field tests may reflect disease progression or variability among examinations. We describe the approaches and perimetric tests used to evaluate glaucomatous visual field progression and factors that are important for identifying progression. These include stimulus size, which area of the visual field to assess (central versus peripheral), and the testing frequency, evaluating which is important to detect change early while minimizing patient testing burden. We also review the different statistical methods developed to identify change. These include trend- and event-based analyses, parametric and nonparametric tests, population-based versus individualized approaches, as well as pointwise and global analyses. We hope this information will prove useful and important to enhance the management of glaucoma patients. Overall, analysis procedures based on series of at least 5 to 6 examinations that require confirmation and persistence of changes, that are guided by the pattern and shape of the glaucomatous visual field deficits, and that are consistent with structural defects provide the best clinical performance.

Improving Visual Field Trend Analysis with OCT and Deeply Regularized Latent-Space Linear Regression

PURPOSE

To investigate whether OCT measurements can improve visual field (VF) trend analyses in glaucoma patients using the deeply regularized latent-space linear regression (DLLR) model.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Training and testing datasets included 7984 VF results from 998 eyes of 592 patients and 1184 VF results from 148 eyes of 84 patients with open-angle glaucoma, respectively. Each eye underwent a series of 8 VF tests with the Humphrey Field Analyzer OCT series obtained within the same observation period.

METHODS

Using pointwise linear regression (PLR), the threshold values of a patient's eighth VF results were predicted using values from shorter VF series (first to second VF tests [VF1-2], first to third VF tests, . . . , to first to seventh VF tests [VF1-7]), and the root mean square error (RMSE) was calculated. With DLLR, OCT measurements (macular retinal nerve fiber layer thickness, the thickness of macular ganglion cell layer and inner plexiform layer, and the thickness of the outer segment and retinal pigment epithelium) that were obtained within the period of shorter VF series were incorporated into the model to predict the eighth VF.

MAIN OUTCOME MEASURES

Prediction accuracy of VF trend analyses.

RESULTS

The mean ± standard deviation RMSE resulting from PLR averaged 27.48 ± 16.14 dB for VF1-2 and 3.98 ± 2.25 dB for VF1-7. Significantly (P < 0.001) smaller RMSEs were obtained from DLLR: 4.57 ± 2.71 dB (VF1-2) and 3.65 ± 2.27 dB (VF1-7).

CONCLUSIONS

It is useful to include OCT measurements when predicting future VF progression in glaucoma patients, especially with short VF series.

Ganglion Cell Complex Analysis in Glaucoma Patients: What Can It Tell Us?

Glaucoma is a group of optic neuropathies characterized by a progressive degeneration of retina ganglion cells (RGCs) and their axons that precedes functional changes detected on the visual field. The macular ganglion cell complex (GCC), available in commercial Fourier-domain optical coherence tomography, allows the quantification of the innermost retinal layers that are potentially involved in the glaucomatous damage, including the retinal nerve fiber (RNFL), ganglion cell and inner plexiform layers. The average GCC thickness and its related parameters represent a reliable biomarker in detecting preperimetric glaucomatous damage. The most accurate GCC parameters are represented by average and inferior GCC thicknesses, and they can be associated with progressive visual field loss. Although the diagnostic accuracy increases with more severe glaucomatous damage and higher signal strength values, it is not affected by increasing axial length, resulting in a more accurate discrimination of glaucomatous damage in myopic eyes with respect to the traditional RNFL thickness. The analysis of the structure-function relationship revealed a good agreement between the loss in retinal sensitivity and GCC thickness. The use of a 10-2° visual field grid, adjusted for the anatomical RGCs displacement, describes more accurately the relationship between RGCs thickness and visual field sensitivity loss.

Validating the efficacy of the binomial pointwise linear regression method to detect glaucoma progression with multicentral database

BACKGROUND/AIM

We previously reported the benefit of applying binomial pointwise linear regression (PLR: binomial PLR) to detect 10-2 glaucomatous visual field (VF) progression. The purpose of the current study was to validate the usefulness of the binomial PLR to detect glaucomatous VF progression in the central 24°.

METHODS

Series of 15 VFs (Humphrey Field Analyzer 24-2 SITA-standard) from 341 eyes of 233 patients, obtained over 7.9±2.1 years (mean±SD), were investigated. PLR was performed by regressing the total deviation of all test points. VF progression was determined from the VF test points analyses using the binomial test (one side, p<0.025). The time needed to detect VF progression was compared across the binomial PLR, permutation analysis of PLR (PoPLR) and mean total deviation (mTD) trend analysis.

RESULTS

The binomial PLR was comparable with PoPLR and mTD trend analyses in the positive predictive value (0.18-0.87), the negative predictive value (0.89-0.95) and the false positive rate (0.057-0.35) to evaluate glaucomatous VF progression. The time to classify progression with binomial PLR (5.8±2.8 years) was significantly shorter than those with mTD trend analysis (6.7±2.8 years) and PoPLR (6.6±2.7 years).

CONCLUSIONS

The binomial PLR method, which detected glaucomatous VF progression in the central 24° significantly earlier than PoPLR and mTD trend analyses, shows promise for improving our ability to detect visual field progression for clinical management of glaucoma and in clinical trials of new glaucoma therapies.

Cluster analysis of computerized visual field and optical coherence tomography–ganglion cell complex defects in high intraocular pressure patients or early stage glaucoma

Purpose:

The aim of the study is to evaluate the relationship between functional defects shown by cluster analysis of computerized visual field and anatomic defects from optical coherence tomography–ganglion cell complex examination in ocular hypertension or eyes affected by glaucoma.

Methods:

205 eyes affected by ocular hypertension (intraocular pressure > 22 mmHg) or early stage glaucoma were enrolled. The age of the patients ranged from 26 to 87 years (average: 61.83 ± 1.54 years). Computerized 30° visual field (Octopus G1x Dynamic strategy) and optical coherence tomography–ganglion cell complex (I-Vue Optovue) analyses were performed for each eye selected; 68 eyes were tested and retested from two to seven times for a total of 320 visual fields and 320 optical coherence tomography–ganglion cell complex examinations. The visual field was considered abnormal with a mean defect < –2 and loss variance > 6. The optical coherence tomography–ganglion cell complex was considered abnormal with a significant focal loss volume (p < 5%) and/or a significant thinning of total, superior, or inferior thickness (p < 5%). Four different groups of examinations were created according to the results of visual field and ganglion cell complex: normal visual field and normal ganglion cell complex (group 1), abnormal visual field and abnormal ganglion cell complex (group 2), normal visual field and abnormal ganglion cell complex (group 3), and abnormal visual field and normal ganglion cell complex (group 4). The cluster analysis of visual fields (EyeSuite software Interzeag CH) was performed only in the visual field of group 3, and the correlation between cluster values and topographical changes at optical coherence tomography–ganglion cell complex was analyzed.

Results:

The results of the ganglion cell complex and visual field examinations matched 247 (77.19%) times. In 143 cases, the examinations belonged to group 1, in 104 to group 2, in 23 to group 3, and, finally, in 50 to group 4. The visual field cluster analysis performed on group 3 showed that the correlation between optical coherence tomography–ganglion cell complex and visual field cluster analysis defects was 100% (both the exams altered). In 72% of them, there was also a topographical correspondence between the visual field and optical coherence tomography–ganglion cell complex defects.

Conclusion:

In the early stages of glaucoma, the visual field cluster analysis seems to be useful to detect some focal defects that can be otherwise underestimated when globally considering the visual field. In group 3, where the conventional analysis of visual field was normal while the optical coherence tomography–ganglion cell complex exam was abnormal, the visual field cluster analysis showed a topographical correlation with optical coherence tomography–ganglion cell complex defects in more than 70% of the examinations performed. In addition, the patients with abnormal visual field and normal optical coherence tomography–ganglion cell complex were older than those with normal visual field and abnormal optical coherence tomography–ganglion cell complex (66.44 ± 3.51 vs 57.04 ± 5.96 years, p < 0.001 (0.0002)). These results confirm that the reliability of a visual field examination is subjective and decreases with age because of its difficulty and the personal compliance of the patient toward this examination.

Early Detection of Glaucomatous Visual Field Progression Using Pointwise Linear Regression With Binomial Test in the Central 10 Degrees

PURPOSE

We previously reported that it was beneficial to apply binomial pointwise linear regression (PLR) to detect 24-2 glaucomatous visual field (VF) progression, compared to mean deviation (MD) trend analysis and permutation analysis of PLR (PoPLR). The purpose of the current study was to validate the usefulness of the binomial PLR method to detect VF progression in the central 10 degrees in glaucoma patients.

DESIGN

Reliability assessment.

METHODS

A series of 15 VFs (Humphrey Field Analyzer 10-2 SITA-standard) from 97 eyes in 69 primary open-angle glaucoma patients, obtained over 8.5 ± 1.3 years (mean ± SD), were investigated. PLR was performed by regressing the total deviation of all test points on the series of 15 VFs. VF progression was determined from the analyses of VF test points using the binomial test (1-sided, P < .025). The time needed to detect VF progression was also investigated. The results were compared with PoPLR and MD trend analyses.

RESULTS

The binomial PLR was comparable to PoPLR and MD trend analyses in the positive predictive value (0.19 to 0.80), the negative predictive value (0.86 to 1.0), and the false positive rate (0.0 to 0.13) to evaluate glaucomatous VF progression. The time needed to detect VF progression (4.2 ± 1.8 years) was significantly shorter with the binomial PLR method compared with PoPLR and MD trend analysis (P = .04, P = .012, respectively).

CONCLUSIONS

The binomial PLR method detected glaucomatous VF progression in the central 10 degrees significantly earlier than PoPLR and MD trend analyses.

Repeated Dexamethasone Intravitreal Implant for the Treatment of Diabetic Macular Oedema Unresponsive to Anti-VEGF Therapy: Outcome and Predictive SD-OCT Features

PURPOSE

To investigate dexamethasone intravitreal implant 0.7 mg (DEX implant) for the treatment of diabetic macular oedema (DME) refractory to anti-vascular endothelial growth factor (anti-VEGF) therapy and evaluate predictive factors.

METHODS

Two-centre retrospective interventional case series, including 40 eyes of 31 patients treated with DEX implant for at least 2 consecutive cycles.

RESULTS

Mean ± SD intervals from implantation to recurrence in the first (4.2 ± 1.0 months) and second cycles (4.0 ± 0.9 months) were not significantly different. Best corrected visual acuity improved significantly (p < 0.001) by 7.0 ± 8.4 letters from baseline to month 2, and by 5.1 ± 6.9 letters between the first and second cycles. Central retinal thickness reduction 2 months after implantation was greater after the first (-194 ± 172 µm) than the second cycle (-134 ± 150 µm). Ellipsoid zone-external limiting membrane (EZ-ELM) disruption score decreased from 1.39 ± 1.16 at baseline to 1.24 ± 1.16 (p = 0.0832) after cycle 1 and remained stable 2 months after cycle 2. Eyes with persisting severe EZ-ELM disruption (score >2, n = 10) 2 months after the first DEX implant showed significantly (p = 0.0153) smaller visual acuity (VA) gains than eyes with less severe (score ≤2) EZ-ELM disruption.

CONCLUSION

Repeated intravitreal DEX injections with average intervals of 4 months are valuable in patients with DME refractory to anti-VEGF therapy. Disorganization of outer retinal layers (EZ-ELM) may predict smaller VA gains if evaluated after initial reduction of macular oedema.