The relationship between better-eye and integrated visual field mean deviation and visual disability

Characterizing Longitudinal Changes in Fear of Falling and Quality of Life in Patients with Varying Levels of Visual Field Damage

PURPOSE

To investigate the relationship between baseline visual field (VF) severity and rates of visual field loss with changes in quality of life (QoL) and fear of falling (FoF) in adults with glaucoma.

METHODS

Prospective cohort study, including participants from the Falls In Glaucoma Study. Quality of life and FoF were assessed annually using the Glaucoma Quality of Life-15 Questionnaire, and the University of Illinois at Chicago FoF Questionnaire, respectively, with higher Rasch-analyzed scores (in logits) indicating better QoL and greater FoF. Mean deviation (MD) values of each eye were collected, with better-eye MD taken as the primary exposure. Change rates in better-eye MD, QoL, and FoF were computed using linear regression. Separate regression models were employed to explore the relationship between baseline better-eye MD and its rate of change with rates of change in QoL and FoF.

RESULTS

The mean (standard deviation) rate of change in better-eye MD was -0.08 dB/year (0.5), rate of QoL change was -0.08 logits/year (0.4), and rate of FoF change was 0.16 logits/year (0.7). At baseline, better-eye MD (per dB worse) was significantly associated with worse baseline QoL (β = -0.10 logits [95% confidence interval [CI]: -0.13, -0.08]) and greater FoF (β = 0.06 logits [95% CI: 0.01, 0.10]). Baseline better-eye MD was associated with no significant change in QoL ( -0.004 logits/year, 95% CI: -0.02, 0.01) or FoF (-0.0001 logits/year, 95% CI: -0.02, 0.02) over time. Change rates in better-eye MD showed significant associations with faster increases in FoF over time (β = 0.26 logits/year [95% CI: 0.06, 0.45]; per dB loss/year), but not with changes in QoL (P = 0.79).

CONCLUSIONS

Patients with glaucoma generally showed worsening of QoL and FoF over time, though the degree of change was modest and not related to the degree of damage at baseline. Faster rates of better-eye MD change alone were associated with faster increases in FoF. Further studies are needed to evaluate the reasons (visual and nonvisual) for changes in QoL and functionality over time and find ways in which QoL and mobility can be improved for those with VF damage.

FINANCIAL DISCLOSURES

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

Impact of Monocular and Binocular Visual Function Parameters on Vision-Related Quality of Life in Glaucoma

PRCIS

This study describes the impact of monocular (M/O) and binocular (B/O) visual function decline, primarily the contrast sensitivity (CS) and visual field (VF) defect severity and its location, on the subjective perception of quality of life (QoL) among the Indian glaucoma population with spared central acuity.

AIM

To investigate the influence of M/O and B/O visual function parameters on vision-related QoL (VRQoL) in glaucoma with spared central visual acuity.

MATERIALS AND METHODS

Glaucoma subjects underwent M/O and B/O visual acuity, CS assessment, followed by the M/O perimetry from which the integrated VF was estimated (B/O summation method). VRQoL was evaluated using the Glaucoma Quality Of Life-15 (GQL-15) and Visual Function Questionnaire-Utility Index (VFQ-UI) questionnaires. The relationship between CS and VF defect (VFD) with the composite VRQoL scores was analyzed.

RESULTS

A total of 154 glaucoma subjects with a median age of 61 (range: 24-83) years were enrolled. Subjects with severe VFD reported poor composite scores for GQL-15 and VFQ-UI when compared with unilateral and mild groups ( P < 0.001, Dunn post hoc). Both the composite scores were negatively correlated with M/O and B/O CS and VF mean deviation ( r range: -0.3 to -0.5, P < 0.001, Spearman rank correlation). B/O VFD in the inferior central zone contributed to poor GQL-15 score [odds ratio: 1.14 (95% CI: 1.10-1.29), P = 0.04] irrespective of sex, whereas females with increasing B/O VFD reported poor QoL score in VFQ-UI [odds ratio: 4.09 (95% CI: 1.77-9.43), p=0.003].

CONCLUSIONS

Poor GQL-15 and VFQ-UI scores were reported with increasing disease severity. B/O VFD in the inferior central region was found to contribute predominantly to the poor GQL-15 scores while both disease severity and sex influenced VFQ-UI scores.

Quality of life in glaucoma

BACKGROUND

An essential goal of glaucoma management is to prevent a patient's visual impairment that compromises their health-related quality of life (QOL). The disease itself, in addition to the medical or surgical treatment, can have a large impact on one's life. We aim to briefly review and evaluate aspects of QOL in glaucoma.

METHODS

The PubMed database was utilized for the literature examination of this review. Keywords that were searched included glaucoma, quality of life, vision-related QOL (VRQOL), quality of life questionnaire, and glaucoma therapy.

RESULTS

The main topics identified and analyzed during the literature review stages include factors affecting VRQOL, the assessment of VRQOL using questionnaires, QOL in early and severe glaucoma, glaucoma and activities of daily living, glaucoma treatments, and new advances in clinically assessing QOL. The study findings indicate a relationship between the deterioration of visual field and the quality of life. The investigation shows that visual loss can result in a range of daily life challenges, which include compromised mental health status and difficulties with driving, reading, and recognizing people.

CONCLUSION

Glaucoma-induced visual field loss can significantly impact different aspects of patients' life, and several methods exist for evaluating changes in quality of life. Quality of life assessments have their limitations as they are subjective. As potential future steps, we suggest exploring technological advancements such as virtual reality to improve patient care and outcomes.

Progressive Visual Field Loss and Subsequent Quality of Life Outcomes in Glaucoma

PURPOSE

To evaluate the association between baseline severity of visual field (VF) damage and the initial rates of VF progression with quality of life (QOL) outcomes over an extended follow-up in glaucoma.

DESIGN

Retrospective cohort study.

METHODS

Both eyes of 167 glaucoma or suspected glaucoma patients were followed for 10.0±0.3 years. The National Eye Institute Visual Function Questionnaire (NEI-VFQ)-25 was performed at the end of the follow-up. Separate linear regression models included the VF parameters of the better eye, the worse eye, and the central and peripheral points of the integrated binocular VF to evaluate the association of baseline and initial rates of change of VF parameters (first half of the follow-up) with NEI-VFQ-25 Rasch-calibrated disability scores over an extended follow-up.

RESULTS

All models demonstrated association of worse baseline severity of VF damage with worse subsequent NEI-VFQ-25 scores. Faster rates of decline in VF mean deviation of the better eye and the mean sensitivity of the central and peripheral test locations of the integrated binocular VF were significantly associated with worse subsequent NEI-VFQ-25 scores. VF parameters of the better eye performed better than those of the worse eye (R2 of 0.21, and 0.15, respectively), and the VF parameters of the central test locations performed better than those of the peripheral test locations (R2 of 0.25, and 0.20, respectively).

CONCLUSIONS

Baseline severity and initial rates of change of VF damage are associated with QOL outcomes over an extended follow-up. Assessment of longitudinal VF changes, especially in better eye, provides prognostic utility to identify glaucoma patients at a higher risk for developing disease-related disability.

Impact of minimally invasive glaucoma surgery on the ocular surface and quality of life in patients with glaucoma

Background:

Minimally invasive glaucoma procedures are emerging as clinically effective and safe glaucoma management approaches; however, evidence regarding quality-of-life outcomes is limited.

Objectives:

To explore the impact of minimally invasive glaucoma surgery (MIGS) combined with phacoemulsification on patient-reported outcomes and clinical parameters related to ocular surface disease in people with glaucoma.

Design:

Retrospective observational study.

Methods:

Fifty-seven consecutive patients were examined prior to undergoing iStent combined with phacoemulsification with or without adjunctive endocyclophotocoagulation and at 4-month follow-up.

Results:

At follow-up, on average patients returned statistically significantly improved scores on glaucoma-specific (GQL-15, p < 0.001; GSS, p < 0.001), general health (EQ-5D, p = 0.02) and ocular surface PROMs (OSDI, p = 0.001). Patients were using fewer eye drops on average after MIGS compared with before surgery (1.1 ± 0.9 versus 1.8 ± 0.8; p < 0.001). Undergoing MIGS was associated with improved tear film break-up time ( p < 0.001) and reduced corneal fluorescein staining ( p < 0.001).

Conclusion:

This retrospective audit shows quality of life and clinical parameters related to the ocular surface are improved following MIGS combined with phacoemulsification in patients previously treated with anti-glaucoma therapy.

Visual Field Loss Impacts Vision-Specific Quality of Life by Race and Ethnicity: The Multiethnic Ophthalmology Cohorts of California Study

PURPOSE

To assess the impact of visual field loss (VFL) on vision-specific quality of life (VSQOL) by race, ethnicity, and age.

DESIGN

Pooled analysis of cross-sectional data from 3 population-based, prospective cohort studies.

PARTICIPANTS

The Multiethnic Ophthalmology Cohorts of California Study (MOCCaS) participants included 6142 Latinos, 4582 Chinese Americans, and 6347 Black Americans from Los Angeles County.

METHODS

A total of 17 071 adults aged 40 years and older completed comprehensive interviews and ophthalmic examinations from 2000 to 2018. VFL was measured using the Humphrey Swedish Interactive Threshold Algorithm Standard 24-2 test as decibels (dB) of mean deviation (MD). Multivariable linear regression was used to evaluate the impact of VFL in the better-seeing eye on self-reported VSQOL scores, adjusting for sociodemographic and clinical covariables. Hierarchical modeling was performed to determine the best-fit model after considering main effects and interactions by race, ethnicity, and age.

MAIN OUTCOME MEASURES

The VSQOL scores were measured using the 25 Item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25). Item response theory was used to model vision-related task and well-being composite scores, and classical test theory was used to calculate 11 vision subscales.

RESULTS

The impact of VFL on VSQOL varied by race and ethnicity. Five-point reductions in task and well-being scores were reached after mild-to-moderate VFL for Latinos (6.7 dB and 7.5 dB), mild-to-moderate VFL for Chinese Americans (7.0 dB and 8.7 dB), and moderate-to-severe VFL for Black Americans (10.1 dB and 12.9 dB), respectively. Differences met statistical significance when comparing Latinos and Black Americans (P < 0.001). Visual field loss had the largest effect on driving among all participants. Driving difficulties were the only VSQOL outcome modified by age; participants aged 65 years and older scored 0.487 lower points per MD of VFL (P < 0.001). Subscales most affected by VFL included role function, mental health, and dependency.

CONCLUSIONS

Race and ethnicity modified the impact of VFL on VSQOL, even after adjusting for sociodemographic covariates. In MOCCaS, Latinos and Chinese Americans reported a greater change in VSQOL than Black Americans for the same level of VFL. Future work should assess whether findings were due to socioeconomic or cultural differences in perception of visual function.

Structure-Function Relationship and Vision-Related Quality of Life in Glaucoma Secondary to Anterior Uveitis: Comparison with Open Angle Glaucoma

Purpose: The aim of this study is to investigate the structure–function characteristics and vision-related quality of life (VR-QoL) in uveitic glaucoma (UG) compared with open-angle glaucoma (OAG). Method: The study included 69 patients with UG and 138 patients with primary open angle glaucoma, normal-tension glaucoma. A 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) was used to evaluate the patients’ VR-QoL. The retinal nerve fiber layer thickness (RNFLT) was measured using optical coherence tomography, and the integrated visual field (IVF) was determined using the best location method. Results: There were no significant differences in the binocular IVF and mean deviation (MD) of the affected eye between the OAG and UG group, whereas the average RNFLT was significant thinner in the OAG group (p = 0.008). The patients with UG showed a significantly lower composite score and five subscales of the VFQ-25, compared with those with OAG (p < 0.05, for all, general linear model). Multivariate linear regression analyses showed that the composite score showed the strongest associations with the whole IVF (β = 1.240, p < 0.001) in the OAG group, whereas in the UG group, a significant association was seen only with the inferior VF of the affected eye (β = 0.596, p = 0.038). Conclusions: The eyes with UG exhibited distinctive structure–function characteristics and worse VR-QoL that differentiated them from OAG eyes.

Comparison of the Automated Pattern-Noise (PANO) Glaucoma Test with the HFA, an FDT Stimulus, and the Fundus Area Cup-to-disk Ratio

AIM AND OBJECTIVE

To compare the results of a new automated glaucoma test-Pattern-Noise (PANO)-to the Humphrey Visual Field Analyzer-II (HFA), the fundus area cup-to-disk ratio (CDR), and a frequency doubling technology (FDT) stimulus.

MATERIALS AND METHODS

This was a prospective study performed in the West-Region of Cameroon. Two hundred and nineteen eyes of 122 adult patients were included with a clinical suspicion of normal-tension or primary open-angle glaucoma and no other major ocular pathology. Eyes were examined with PANO, HFA (24-2 SITA standard), and FDT-stimulus in a randomized order followed by clinical assessment of the CDR.

RESULTS

Parametric correlation of the mean contrast threshold of PANO with the mean contrast threshold of FDT-stimulus, total deviation of HFA, and area CDR was 0.94, -0.85, and 0.62, respectively (p < 0.001 for all values). Spatial distribution of sensitivity thresholds is highly correlated (p < 0.001) at all points in the visual field between PANO and HFA. With cut-off values of 3 ± 1 dB for HFA mean deviation and 4 ± 1 for PANO mean contrast threshold and after eliminating borderline cases, PANO's sensitivity was 95% and specificity 60%. The mean patient age was 45.2 ± 15.8 years. Mean thresholds of PANO and FDT-stimulus decreased with increasing age. Mean examination time was 7.1 ± 1.8 minutes for PANO, 5.9 ± 1.3 minutes for HFA, and 4.7 ± 1.3 minutes for FDT-stimulus. The mean percentage of false-positives per examination was 4.95% for PANO, 4.62% (p = 0.025) for FDT-stimulus, and 2.10% for HFA.

CONCLUSION

The results showed that PANO was successful in suspecting the presence of glaucoma. Pattern-Noise examination led to findings that were significantly correlated to HFA, FDT stimulus, and area CDR. Some patterns of defect were also correlated. Furthermore, PANO showed a reasonable examination time and error rate.

CLINICAL SIGNIFICANCE

Affordable and robust visual field devices are lacking in large parts of the developing world. Comparing them to established methods is a prerequisite to their clinical use.

HOW TO CITE THIS ARTICLE

Hannen T, El-Khoury S, Patel R, et al. Comparison of the Automated Pattern-Noise (PANO) Glaucoma Test with the HFA, an FDT Stimulus, and the Fundus Area Cup-to-disk Ratio. J Curr Glaucoma Pract 2021;15(3):132-138.

Impact of Visual Field Loss on Vision-Specific Quality of Life in African Americans: The African American Eye Disease Study

PURPOSE

To elucidate how visual field loss (VFL) impacts self-reported vision-specific quality of life (VSQOL) in African Americans, who experience a disproportionate burden of visual impairment.

DESIGN

Cross-sectional, population-based cohort.

METHODS

Eligible participants (n = 7,957) were recruited who self-identified as African American, were aged 40 years or older, and resided in Inglewood, California, USA. A total of 6,347 participants (80.0%) completed clinical eye examinations. Total mean deviation (MD) of VFL was measured bilaterally as decibels (dB) using the Humphrey SITA Standard 24-2 test. VSQOL was measured using the National Eye Institute Visual Function Questionnaire (NEI-VFQ 25) and scored using item response theory (IRT).

RESULTS

Participants with reliable data (n = 5,121) had a mean age of 60.7 years (standard deviation 11.0); those with worse VFL were older; had more comorbidities, lower income, less education, and worse visual acuity; and were more likely to be unemployed and depressed. Using IRT analysis, a change in VF of 6.2 (95% confidence interval [CI]: 5.3, 7.7) dB and 9.2 (95% CI: 7.5, 11.9) dB was necessary to observe a meaningful (5-point) difference in vision-related task and emotional well-being scores, respectively. VFL had the greatest impact on self-reported driving ability (6.0 dB [95% CI: 5.2, 7.1]), followed by satisfaction with general vision, near vision, vision-related mental health, and peripheral vision.

CONCLUSIONS

The strongest impact of VFL reported by African Americans was on their ability to complete visual tasks, especially for driving. An effect of VFL on emotional well-being also was observed, but the magnitude of association was about 50% lower for well-being compared to that of task.

Quality of Life in Primary Open-Angle Glaucoma and Cataract: An Analysis of VFQ-25 and OSDI From the iStent inject® Pivotal Trial

OBJECTIVE

To assess quality of life (QOL) as measured by patient-reported outcomes (PRO) within the iStent inject® pivotal trial.

DESIGN

Randomized controlled trial analysis of secondary outcomes.

METHODS

The Vision Function Questionnaire (VFQ-25) and Ocular Surface Disease Index (OSDI) questionnaire were administered at baseline and at months 1, 6, 12, and 24. PRO responders were defined as patients reaching improvement based on minimally important differences.

RESULTS

A total of 505 patients were randomized (386 iStent inject® [Glaukos], 119 surgery alone). The iStent inject® group exhibited a greater percentage of PRO responders across all follow-up visits over 24 months, averaging 58.0% vs 45.8%; P < .05 for VFQ-25 composite scores and 56.7% vs 48.9%; P < .05 for OSDI composite scores. Odds of being a responder in the iStent inject® group was 60% (P < .05) higher for the VFQ-25 and 32% (P > .05) higher for the ODSI. Driving (49.0% vs 28.8%; P < .05), ocular pain (59.3% vs 47.2%; P < .05), and general vision (71.8% vs 60.0%; P < .05) were the VFQ-25 subscales responsible for differences between treatment groups. At month 24, 76.5% of VFQ-25 responders and 62.5% of nonresponders were medication free regardless of treatment group (P < .05).

CONCLUSIONS

Exploratory analysis suggests that by reducing medication dependence, implantation with the micro-scale iStent inject® device with cataract surgery may improve QOL vs cataract surgery alone over 24 months, with improvements influenced by ocular symptoms and vision-related activities.

A Novel Approach to Measuring Binocular Visual Fields in Glaucoma

PRECIS

Combined average visual field index (VFI) is a simple, novel tool for binocular visual field which agrees with the existing binocular integrated visual field (IVF) model, as well as patient reported activity limitation in glaucoma.

PURPOSE

The aim was to determine the correlation between novel models of binocular visual field with the existing IVF and glaucoma activity limitation (GAL-9).

MATERIALS AND METHODS

IVFs were calculated from the monocular visual fields of 58 patients with primary glaucoma and the novel binocular visual field models termed binocular summation visual field index (BiSumVFI) and combined average visual field index (CaVFI) were derived from the VFIs of both fields. GAL-9 questionnaire was administered to the patients. The relationship between IVF and the 2 newer models of binocular fields were determined and the correlation of IVF, BiSumVFI, and CaVFI with GAL-9 was estimated.

RESULTS

A very strong correlation was seen between IVF and BiSumVFI (r=-0.913, P<0.001, confidence interval: -0.958 to -0.821) and also between IVF and CaVFI (r=-0.896, P<0.001, confidence interval: -0.947 to -0.802). Linear regression analysis showed a significant R2 of 0.902 (P<0.001) to predict IVF from BiSumVFI and R2 of 0.847 (P<0.001) to predict IVF from CaVFI. IVF, BiSumVFI, and CaVFI correlated moderately and significantly with GAL-9 with correlation coefficients of 0.481, -0.499, and -0.505, respectively.

CONCLUSION

The binocular summation VFI and combined average VFI models of binocular visual field are good predictors of IVF in glaucoma. They correlate well with the existing IVF model in estimating patients' perception of activity limitation in glaucoma.

Comparison of Patient-Reported Functional Recovery From Different Types of Ophthalmic Surgery

PURPOSE

To characterize and compare patient-reported recovery of function after cataract or glaucoma surgery using a novel visual analog scale.

DESIGN

Prospective observational cohort study.

METHODS

Daily for 2 weeks and weekly thereafter, patients recovering from trabeculectomy, tube shunt implantation, or cataract extraction (CE) completed a diary-style questionnaire including visual analog scales (VASs; scored 0-100) grading pain and global function. Clinical examination data and medical histories were collected. Generalized estimating equation models evaluated associations between VAS function scores and pain or visual acuity (VA) and compared scores between surgery types.

RESULTS

Among 51 participants followed for 12 weeks, tube shunt placement reduced postoperative day 1 (POD1) function by 47 of 100 points vs CE (P = .006), while trabeculectomy did not reduce POD1 function vs CE (P = .33). After CE, trabeculectomy, and tube shunt placement, average VAS function scores increased 13.94 per week for 2 weeks (P < .001), 4.18 per week for 4 weeks (P = .02), and 7.76 per week for 7 weeks (P < .001), respectively. After those timepoints, there was no further significant change. Beyond 2 weeks, pain levels plateaued, and VA returned to baseline across surgery types; function was inversely related to pain or VA only for the first 2 or 4 weeks, respectively.

CONCLUSIONS

Patients recovering from cataract and glaucoma surgery report reduced function in the postoperative period. Tube shunt implantation causes greater morbidity than trabeculectomy, and both are associated with slower improvement than CE. Early postoperative function is associated with VA and pain, but neither fully explains reported impairment. A VAS for function may efficiently capture postoperative recovery.

The Computerized Glaucoma Visual Function Test: A Pilot Study Evaluating Computer-Screen Based Tests of Visual Function in Glaucoma

Purpose

We aimed to develop and evaluate the Computerized Glaucoma Visual Function Test (CoGVFT), among a cohort of glaucoma patients, and identify potential new items to optimize the test.

Method

A cross-sectional study involving 84 patients with open-angle glaucoma of varying severity and 18 controls without glaucoma were recruited. Better and worse eye visual field parameters, visual acuity, contrast sensitivity, 6-Part Cognitive Impairment Test (6CIT) and Glaucoma Activity Limitation-9 (GAL-9) questionnaire responses were recorded. The CoGVFT was administered to all participants. Rasch analysis was used to assess the psychometric properties of the CoGVFT, which was then evaluated with criterion, convergent, and divergent validity tests. Regression modeling determined factors predictive of CoGVFT performance.

Results

The 38-item CoGVFT demonstrated convergent validity with statistically significant differences in glaucoma severity groups (P < 0.001, analysis of variance). The correlation coefficient for CoGVFT person measures (logits) with GAL-9 person measures (logits) and better eye (BE) mean deviation was 0.528 (P < 0.001) and 0.762 (P < 0.001), respectively, demonstrating convergent validity. Divergent validity was suboptimal as the 6CIT score demonstrated moderate correlation (r = 0.463, P < 0.001) with CoGVFT person measures (logits). Multivariable analysis revealed that better BE contrast sensitivity, lower age, and better BE visual acuity were associated with better CoGVFT performance (P < 0.001).

Conclusions

The CoGVFT retains most of the features of its predecessor to estimate vision-based activity limitation related to glaucoma.

Translational Relevance

The CoGVFT is an easily accessible tool that can potentially be used in the community to help detect undiagnosed glaucoma in the population.

The worse eye revisited: Evaluating the impact of asymmetric peripheral vision loss on everyday function

In instances of asymmetric peripheral vision loss (e.g., glaucoma), binocular performance on simple psychophysical tasks (e.g., static threshold perimetry) is well-predicted by the better seeing eye alone. This suggests that peripheral vision is largely 'better-eye limited'. In the present study, we examine whether this also holds true for real-world tasks, or whether even a degraded fellow eye contributes important information for tasks of daily living. Twelve normally-sighted adults performed an everyday visually-guided action (finding a mobile phone) in a virtual-reality domestic environment, while levels of peripheral vision loss were independently manipulated in each eye (gaze-contingent blur). The results showed that even when vision in the better eye was held constant, participants were significantly slower to locate the target, and made significantly more head- and eye-movements, as peripheral vision loss in the worse eye increased. A purely unilateral peripheral impairment increased response times by up to 25%, although the effect of bilateral vision loss was much greater (>200%). These findings indicate that even a degraded visual field still contributes important information for performing everyday visually-guided actions. This may have clinical implications for how patients with visual field loss are managed or prioritized, and for our understanding of how binocular information in the periphery is integrated.

The Relationship Between Binocular Visual Field Loss and Various Stages of Monocular Visual Field Damage in Glaucoma Patients

PURPOSE

To investigate the effects of monocular visual field loss severity on binocular visual field (BVF) loss in primary angle-closure glaucoma, primary open-angle glaucoma, and normal tension glaucoma patients.

MATERIALS AND METHODS

In this observational cross-sectional study, 250 glaucoma patients and 31 healthy participants were assigned to groups according to the stage of monocular visual field loss in both eyes; normal, early, moderate, or severe. BVF assessments were determined via integrated visual field and Esterman binocular visual evaluations. Monocular and BVF parameters were compared within and among groups.

RESULTS

In patients with one eye at normal or early stage and the other at severe stage, the average integrated mean deviations (MDs) were [mean (SD)], -1.67 (1.39), and -3.27 (2.05) dB, respectively, and the average Esterman scores were >95% [99.17% (1.89%), 96.08% (3.99%), respectively]. Where both eyes had progressed to moderate or severe damage (moderate/moderate, moderate/severe, or severe/severe), the average integrated MDs were worse than -6 dB, and the mean Esterman scores in the moderate/moderate and the moderate/severe damage groups were still >90% [94.20% (5.96%), 94.32% (4.95%), respectively], but it dropped rapidly from >90% to 68.44% (26.27%) when both eyes were at severe stage.

CONCLUSIONS

The BVF can remain relatively intact provided one eye is at the normal or early stage. Significant BVF defects measured by integrated MD were evident when both eyes had progressed to moderate or severe stage, and significant Esterman BVF defects were only detected when both eyes had advanced to a severe stage.

Reading Ability in Primary Open-angle Glaucoma: Evaluation with Radner Reading Charts

SIGNIFICANCE

This study determined the impact of visual disabilities caused by glaucoma on the patient's everyday life and emphasized the importance of developing strategies to improve reading ability in primary open-angle glaucoma (POAG) patients.

PURPOSE

The purposes of this study were to investigate the reading performances of patients affected by POAG using the Italian version of the Radner Reading Charts and to test the presence of correlation between visual field (VF) damage and reading parameters.

METHODS

In this cross-sectional observational study, all patients underwent a complete ophthalmic evaluation including VF testing and evaluation of reading performance using the Radner Reading Charts. The parameters for testing reading performance were reading acuity in logRAD, reading speed in words per minute, maximum reading speed, critical print size, and reading mistakes. Primary open-angle glaucoma and healthy groups were compared using the Mann-Whitney U test. The correlation between VF and reading parameters in glaucomatous eyes was assessed using Spearman correlation analysis. Based on VF mean deviation, each POAG patient had differences in reading performance between his/her best and worst eyes when compared using the paired Wilcoxon test. Statistical significance was set at P ≤ .05.

RESULTS

Eighty POAG patients and 60 healthy controls were enrolled. Glaucomatous subjects read slowly (166.63 ± 29.40 vs. 193.84 ± 26.20 words per minute, P < .0001) and made more mistakes than did healthy subjects. The critical print size for POAG patients was larger than the one for controls (0.52 ± 0.18 vs. 0.62 ± 0.16, P < .0001). Reading parameters showed a moderate correlation with VF mean deviation. The reading parameters were significantly impaired in the worst eye, and this result confirms the impact of VF loss on reading ability.

CONCLUSIONS

This study demonstrated that glaucomatous patients read slowly and with more errors. Reading performances showed a good correlation with VF defect.

Correlation Between Visual Function and Performance of Simulated Daily Living Activities in Glaucomatous Patients

PURPOSE

To analyze the correlations between functional clinical tests and the performance of glaucoma patients in simulated daily living activities.

PATIENTS AND METHODS

Thirty-two patients with chronic glaucoma, followed at the Quinze-Vingts National Ophthalmology Hospital, were included. All patients had a clinical evaluation of visual function including best-corrected visual acuity, contrast sensitivity, and monocular and binocular visual field (VF) tests. Four different simulated activities of daily living were evaluated in standardized artificial platforms (StreetLab and HomeLab): "mobility" and an obstacle avoidance task in an artificial street, "reaching and grasping" large and small objects on a kitchen work surface, "localization of people" and "face orientation recognition." Patient performance in the different tasks was correlated with VF evaluation including integrated binocular visual field (IVF), VF mean deviation (MD) of the better and the worse eye, Esterman binocular VF, best-corrected visual acuity, and contrast sensitivity.

RESULTS

The IVF score was significantly correlated with "localization of people" time (r=0.49; P=0.003), "face orientation recognition" time (r=0.50; P=0.002), and "movement onset" for reaching and grasping small objects (r=0.38; P=0.029). The MD of the better eye appeared significantly correlated with "face orientation recognition" time (r=-0.44; P=0.009) and "localization of people" time (r=-0.46; P=0.005). The Esterman score appeared significantly correlated with "mobility time" (r=-0.40; P=0.018), "localization of people" (r=-0.37; P=0.030), "face orientation recognition" times (r=-0.39; P=0.024), and "movement onset" for reaching and grasping large objects (r=-0.43; P=0.015).

CONCLUSIONS

The IVF score and the MD of the better eye appeared to better evaluate "reaching and grasping," "face orientation recognition," and "localization of people" simulated tasks, whereas for the "mobility" task, the Esterman VF seemed more useful. The precise evaluation of the glaucoma patient's ability to perform everyday life tasks is complex and may require both monocular and binocular VF tests.

2015 Glenn A. Fry Award Lecture: Driving toward a New Vision: Understanding the Role of Vision in Driving

More than 90% of the sensory information that we use for driving is estimated to be visual. However, there is ongoing debate regarding the extent to which different ocular conditions and types of visual impairment affect driving performance and which visual functions are most important for safe driving. My program of research has sought to address these questions using a range of experimental approaches including measures of real-world driving performance on a closed-circuit driving course and under in-traffic conditions. This article provides a current overview of how visual impairment affects driving ability and safety and also highlights the visual challenges of nighttime driving, including the visibility of vulnerable road users, based on the wider research literature, as well as providing a snapshot of some of my own studies. Emphasis is placed on those studies that are relevant to assessing a patient's visual fitness to drive, as well as providing appropriate advice regarding the impact of common visual impairments on driving ability and safety.

Vision Preference Value Scale and Patient Preferences in Choosing Therapy for Symptomatic Vitreomacular Interface Abnormality

Importance

While symptomatic vitreomacular interface abnormalities (VIAs) are common, assessment of vision preference values and treatment preferences of these may guide treatment recommendations by physicians and influence third-party payers.

Objective

To determine preference values that individuals with VIA assign to their visual state and preferences of potential treatments.

Design, Setting, and Participants

In this cross-sectional one-time questionnaire study conducted between December 2015 and January 2017, 213 patients from tertiary care referral centers in Thailand, the United Kingdom, and the United States were studied. Patients with symptomatic VIA diagnosed within 1 year of data collection, visual acuity less than 20/20 OU, and symptoms ascribed to VIAs were included. Data were analyzed from January 2017 to November 2017.

Main Outcomes and Measures

The primary end points were overall mean preference value that individuals with VIA assigned to their visual state and patients' preferences for potential treatments. Preference values were graded on a scale from 0 to 1, with 0 indicating death and 1 indicating perfect health with perfect vision.

Results

Of the 213 included patients, 139 (65.3%) were women, and the mean (SD) age was 65.6 (7.7) years. Diagnoses included epiretinal membrane (n = 100 [46.9%]), macular hole (n = 99 [46.5%]), and vitreomacular traction (n = 14 [6.6%]). The mean (SD) vision preference value was 0.76 (0.15), without differences identified among the 3 VIA types. More participants were enthusiastic about vitrectomy (150 [71.1%]) compared with intravitreal injection (120 [56.9%]) (difference, 14.2%; 95% CI, 5.16-23.3; P = .002). Adjusted analyses showed enthusiasm for vitrectomy was associated with fellow eye visual acuity (odds ratio, 10.99; 95% CI, 2.01-59.97; P = .006) and better-seeing eye visual acuity (odds ratio, 0.03; 95% CI, 0.001-0.66; P = .03). Overall enthusiasm for treatment was associated with fellow eye visual acuity (odds ratio, 7.22; 95% CI, 1.29-40.40; P = .02). Overall, most participants (171 [81.0%]) were enthusiastic about surgery, injection, or both.

Conclusions and Relevance

Study participants reported similar preference values among 3 types of VIAs. The data suggest that most patients with these conditions would be enthusiastic about undergoing vitrectomy or an injection to treat it, likely because of the condition's effect on visual functioning, although there may be a slight preference for vitrectomy at this time.

A New Graphical Tool for Assessing Visual Field Progression in Clinical Populations

Purpose

We demonstrate a new approach for assessing and visualizing visual field (VF) progression in clinics.

Methods

Two summary measures for VF progression, Rate of Progression (RP) and Loss of Sight Years (LSY), are combined with a novel visualization (Hedgehog Plots). RP is calculated per eye using linear regression of mean deviation (MD) against time of follow-up. LSY is a novel parameter, linked to actuarial data, which estimates the number of years that a patient will have advanced bilateral VF loss in their predicted remaining lifetime. Every eye is given a rank within the sample based on RP and LSY allowing for “priority” patients to be identified. We illustrate differences between the parameters with an experiment comparing the cases flagged as “priority” by each method using data from 1263 VF records.

Results

RP for every eye in a “clinic” can be visualized and assessed using a Hedgehog Plot. Eyes are ranked against all other eyes by RP and LSY; these parameters provide different and complementary information on a patient's VF progression status. A purpose written interactive application demonstrating the techniques is available in the public domain at https://crabblab.shinyapps.io/hedgehog.

Conclusion

Hedgehog Plots provide a tool for visualizing VF progression in groups of patients and can be used potentially to prioritize monitoring resources.

Translational Relevance

This study illustrates a novel visualization technique and an interactive application that can be used to help determine VF progression in large groups of patients.

Objective Assessment of Activity Limitation in Glaucoma with Smartphone Virtual Reality Goggles: A Pilot Study

Purpose

To evaluate the use of smartphone-based virtual reality to objectively assess activity limitation in glaucoma.

Methods

Cross-sectional study of 93 patients (54 mild, 22 moderate, 17 severe glaucoma). Sociodemographics, visual parameters, Glaucoma Activity Limitation-9 and Visual Function Questionnaire – Utility Index (VFQ-UI) were collected. Mean age was 67.4 ± 13.2 years; 52.7% were male; 65.6% were driving. A smartphone placed inside virtual reality goggles was used to administer the Virtual Reality Glaucoma Visual Function Test (VR-GVFT) to participants, consisting of three parts: stationary, moving ball, driving. Rasch analysis and classical validity tests were conducted to assess performance of VR-GVFT.

Results

Twenty-four of 28 stationary test items showed acceptable fit to the Rasch model (person separation 3.02, targeting 0). Eleven of 12 moving ball test items showed acceptable fit (person separation 3.05, targeting 0). No driving test items showed acceptable fit. Stationary test person scores showed good criterion validity, differentiating between glaucoma severity groups (P = 0.014); modest convergence validity, with mild to moderate correlation with VFQ-UI, better eye (BE) mean deviation, BE pattern deviation, BE central scotoma, worse eye (WE) visual acuity, and contrast sensitivity (CS) in both eyes (R = 0.243–0.381); and suboptimal divergent validity. Multivariate analysis showed that lower WE CS (P = 0.044) and greater age (P = 0.009) were associated with worse stationary test person scores.

Conclusions

Smartphone-based virtual reality may be a portable objective simulation test of activity limitation related to glaucomatous visual loss.

Translational Relevance

The use of simulated virtual environments could help better understand the activity limitations that affect patients with glaucoma.

Predicting Vision-Related Disability in Glaucoma

PURPOSE

To present a new methodology for investigating predictive factors associated with development of vision-related disability in glaucoma.

DESIGN

Prospective, observational cohort study.

PARTICIPANTS

Two hundred thirty-six patients with glaucoma followed up for an average of 4.3±1.5 years.

METHODS

Vision-related disability was assessed by the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) at baseline and at the end of follow-up. A latent transition analysis model was used to categorize NEI VFQ-25 results and to estimate the probability of developing vision-related disability during follow-up. Patients were tested with standard automated perimetry (SAP) at 6-month intervals, and evaluation of rates of visual field change was performed using mean sensitivity (MS) of the integrated binocular visual field. Baseline disease severity, rate of visual field loss, and duration of follow-up were investigated as predictive factors for development of disability during follow-up.

MAIN OUTCOME MEASURES

The relationship between baseline and rates of visual field deterioration and the probability of vision-related disability developing during follow-up.

RESULTS

At baseline, 67 of 236 (28%) glaucoma patients were classified as disabled based on NEI VFQ-25 results, whereas 169 (72%) were classified as nondisabled. Patients classified as nondisabled at baseline had 14.2% probability of disability developing during follow-up. Rates of visual field loss as estimated by integrated binocular MS were almost 4 times faster for those in whom disability developed versus those in whom it did not (-0.78±1.00 dB/year vs. -0.20±0.47 dB/year, respectively; P < 0.001). In the multivariate model, each 1-dB lower baseline binocular MS was associated with 34% higher odds of disability developing over time (odds ratio [OR], 1.34; 95% confidence interval [CI], 1.06-1.70; P = 0.013). In addition, each 0.5-dB/year faster rate of loss of binocular MS during follow-up was associated with a more than 3.5 times increase in the risk of disability developing (OR, 3.58; 95% CI, 1.56-8.23; P = 0.003).

CONCLUSIONS

A new methodology for classification and analysis of change in patient-reported quality-of-life outcomes allowed construction of models for predicting vision-related disability in glaucoma.

Tolerable rates of visual field progression in a population-based sample of patients with glaucoma

AIMS

To provide population-based data on the maximum tolerable rate of progression to avoid visual impairment (maxTRoP_VI) and blindness (maxTRoP_BL) from open-angle glaucoma (OAG).

METHODS

Participants with OAG in the Thessaloniki Eye Study (cross-sectional, population-based study in a European population) were included in the analysis. Visual impairment was defined as mean deviation (MD) equal to or worse than -12dB and blindness as MD equal to or worse than -24dB. Additional thresholds for visual impairment were tested. For each participant maxTRoP_VI was defined as the rate of progression which would not lead to visual impairment during expected lifetime. MaxTRoP_BL was defined accordingly. Both parameters were calculated for each OAG subject using age, sex, MD and life expectancy data. The eye with the better MD per subject was included in the analysis.

RESULTS

Among 135 subjects with OAG, 123 had reliable visual fields and were included in the analysis. The mean age was 73±6 years and the median MD was -3.65±5.28dB. Among those, 69.1% would have a maxTRoP_VI slower than -1dB/year and 18.7% would have a maxTRoP_VI between -1 and -2dB/year. Also, 72.4% would have a maxTRoP_BL slower than -2dB/year. For all tested thresholds for visual impairment, approximately 86% of the OAG study participants would not be able to tolerate a rate of progression equal to or faster than -2dB/year.

CONCLUSIONS

The majority of patients with glaucoma in our study would have a maximum tolerable rate of progression slower than -1dB/year in their better eye. Patient-tailored strategies to monitor the visual field are important, but raise the issue of feasibility with regard to the number of visual field tests needed.

Association Between Undetected 10-2 Visual Field Damage and Vision-Related Quality of Life in Patients With Glaucoma

Importance

Recent evidence supports the presence of macular damage (within 8° of the central field) to retinal ganglion cells and associated central visual field (VF) defects in glaucoma, even in early stages. Despite this, to our knowledge, the association of 10-2 VF damage with vision-related quality of life (QOL) has not been well studied.

Objective

To determine the association between QOL and visual function as measured by 24-2 and 10-2 VFs in patients with primary open-angle glaucoma and to test the hypothesis that patients with vision-related QOL disproportionate to their 24-2 VF status may exhibit 10-2 damage overlooked by the 24-2 test.

Design, Setting, and Participants

In this cross-sectional analysis of observational cohort study data taken from a tertiary care specialty practice, 113 patients with glaucoma with the entire range of 24-2 VF damage completed the National Eye Institute Visual Function Questionnaire (NEI VFQ-25). Data were collected from May 2014 to January 2015 and were analyzed from March 2016 to May 2016.

Interventions

Standardized binocular 24-2 and 10-2 VF sensitivities were calculated for each patient.

Main Outcomes and Measures

Association of binocular 24-2 and 10-2 VF sensitivity with Rasch-calibrated NEI VFQ-25 scores. Detection of outliers was based on Cook distance of the regression of binocular 24-2 and NEI VFQ-25 score. Outlier association with QOL was then assessed using a linear regression model, with binocular 10-2 VF sensitivity as the independent variable.

Results

Of the 113 patients, the mean (SD) age was 70.1 (10.9) years, and 51 (45.1%) were male and 71 (62.8%) were white. The composite NEI VFQ-25 score was associated with both binocular 24-2 (β = 1.95; 95% CI, 0.47-3.43; P = .01) and 10-2 (β = 2.57; 95% CI, 1.12-4.01; P = .001) sensitivities, but the 10-2 VF univariable model showed an almost 2-fold better fit to the data (R2 = 9.2% vs 4.9%). However, the binocular 10-2 sensitivities of 24-2 outliers had the strongest association with the composite NEI VFQ-25 scores (β = 2.78; 95% CI, 0.84-4.72; P = .006.) and the best fit to the data (R2 = 18.2%.).

Conclusions and Relevance

The 10-2 VF model showed a stronger association with NEI VFQ-25 score than the 24-2 VF model. Patients with disproportionately low quality of vision relative to patients with 24-2 VF damage may have damage on the central field missed by the 24-2 grid. Future prospective testing, including additional dimensions of quality of life, is indicated.

Evidence-based Criteria for Assessment of Visual Field Reliability

PURPOSE

Assess the impact of false-positives (FP), false-negatives (FN), fixation losses (FL), and test duration (TD) on visual field (VF) reliability at different stages of glaucoma severity.

DESIGN

Retrospective.

PARTICIPANTS

A total of 10 262 VFs from 1538 eyes of 909 subjects with suspect or manifest glaucoma and ≥5 VF examinations.

METHODS

Predicted mean deviation (MD) was calculated with multilevel modeling of longitudinal data. Differences between predicted and observed MD (ΔMD) were calculated as a reliability measure. The impact of FP, FN, FL, and TD on ΔMD was assessed using multilevel modeling.

MAIN OUTCOME MEASURES

ΔMD associated with a 10% increment in FP, FN, and FL, or a 1-minute increase in TD.

RESULTS

FL had little impact on ΔMD (<0.2 decibels [dB] per 10% abnormal catch trials), and no level of FL produced ≥1 dB of ΔMD at any disease stage. FP yielded greater than expected MD, with a 10% increment in abnormal catch trials associated with a ΔMD = 0.42, 0.73, and 0.66 dB in mild (MD >-6 dB), moderate (-6 ≤MD <-12 dB), and severe (-12 ≤MD ≤-20 dB) disease, respectively, up to 20% abnormal catch trials, and a ΔMD = 1.57, 2.06, and 3.53 dB beyond 20% abnormal catch trials. FNs generally produced observed MDs below expected MDs. FN were minimally impactful up to 20% abnormal catch trials (ΔMD per 10% increment >-0.14 dB at all levels of severity). Beyond 20% abnormal catch trials, each 10% increment in abnormal catch trials was associated with a ΔMD = -1.27, -0.53, and -0.51 dB in mild, moderate, and severe disease, respectively. |ΔMD| ≥1 dB occurred with 22% FP and 26% FN in early, 14% FP and 34% FN in moderate, and 16% FP and 51% FN in severe disease. A 1-minute increment in TD produced ΔMDs between -0.35 and -0.40 dB.

CONCLUSIONS

FL have little impact on reliability in patients with established glaucoma. FP, and to a lesser extent FNs and TD, significantly affect reliability. The impact of FP and FN varies with disease severity and over the range of abnormal catch trials. On the basis of our findings, we present evidence-based, severity-specific standards for classifying VF reliability for clinical or research applications.

Evaluation of Central and Peripheral Visual Field Concordance in Glaucoma

Purpose

The purpose of this study was to characterize the extent to which central visual field (VF) loss reflects peripheral VF loss in patients with varying degrees of glaucoma severity.

Methods

A total of 232 patients with glaucoma or suspect glaucoma completed static central VF testing using the 24-2 pattern and peripheral VF testing using the suprathreshold 30-60 pattern. Points from 24-2 tests were reclassified as normal/abnormal based on pattern deviation values.

Results

Strong positive correlations (r ≥ 0.7) were observed between the proportion of abnormal central and peripheral points for the full VF, superior hemifield, and inferior hemifield, although the percentage of total central and peripheral abnormal points differed by ≥10% in 45% of eyes. In eyes with an average of 10%–40% abnormal points in the central and peripheral VFs, 12.0% more abnormal peripheral points were noted compared with the percentage of abnormal central points (P < 0.001; SD, 16.7%; range, 61% more to 37% less). In eyes with an average of 60%–90% abnormal points in the central and peripheral VFs, 16.4% fewer abnormal peripheral points were noted compared with the percentage of abnormal central points (P = 0.04; SD, 20.9%; range, 19% more to 49% less).

Conclusions

Central 24-2 testing generally reflects the extent of damage to the more peripheral VF in glaucoma, although significant disagreement exists for individual eyes. Further work is needed to determine whether integration of peripheral test points can improve detection of true VF loss in early glaucoma or be useful in monitoring progressive glaucomatous damage to areas of preserved VF in advanced glaucoma.

Impact of Glaucoma and Dry Eye on Text-Based Searching

PURPOSE

We determine if visual field loss from glaucoma and/or measures of dry eye severity are associated with difficulty searching, as judged by slower search times on a text-based search task.

METHODS

Glaucoma patients with bilateral visual field (VF) loss, patients with clinically significant dry eye, and normally-sighted controls were enrolled from the Wilmer Eye Institute clinics. Subjects searched three Yellow Pages excerpts for a specific phone number, and search time was recorded.

RESULTS

A total of 50 glaucoma subjects, 40 dry eye subjects, and 45 controls completed study procedures. On average, glaucoma patients exhibited 57% longer search times compared to controls (95% confidence interval [CI], 26%-96%, P < 0.001), and longer search times were noted among subjects with greater VF loss (P < 0.001), worse contrast sensitivity (P < 0.001), and worse visual acuity (P = 0.026). Dry eye subjects demonstrated similar search times compared to controls, though worse Ocular Surface Disease Index (OSDI) vision-related subscores were associated with longer search times (P < 0.01). Search times showed no association with OSDI symptom subscores (P = 0.20) or objective measures of dry eye (P > 0.08 for Schirmer's testing without anesthesia, corneal fluorescein staining, and tear film breakup time).

CONCLUSIONS

Text-based visual search is slower for glaucoma patients with greater levels of VF loss and dry eye patients with greater self-reported visual difficulty, and these difficulties may contribute to decreased quality of life in these groups.

TRANSLATIONAL RELEVANCE

Visual search is impaired in glaucoma and dry eye groups compared to controls, highlighting the need for compensatory strategies and tools to assist individuals in overcoming their deficiencies.

Binocular Measures of Visual Acuity and Visual Field versus Binocular Approximations

PURPOSE

To assess the relationship of binocular visual function tests with binocular approximations using data from the Collaborative Initial Glaucoma Treatment Study (CIGTS).

DESIGN

Case series based on existing data from a clinical trial.

PARTICIPANTS

Six hundred seven patients with newly diagnosed open-angle glaucoma from the CIGTS.

METHODS

Monocular visual field (VF) and visual acuity (VA) tests were performed at baseline and every 6 months thereafter. Binocular tests of visual function (Esterman VF score, binocular VA) were added to the CIGTS protocol 3 years into the study. The binocular approximations of binocular visual function were better or worse eye, average eye, better or worse location, and binocular summation or pointwise binocular summation. Associations between binocular tests and binocular approximations to represent binocular visual function were assessed with Pearson's correlations (r), as was the relationship between vision-related quality of life (VR QOL; Visual Activities Questionnaire [VAQ] and the 25-item National Eye Institute Visual Function Questionnaire [NEI VFQ-25]) and binocular tests or binocular approximations of visual function.

MAIN OUTCOME MEASURES

Binocular visual function (VF and VA) and VR QOL.

RESULTS

Five hundred seventy-five patients underwent at least 1 binocular visual function test. The Esterman score was correlated significantly with all binocular approximations of VF, with r values ranging from 0.31 (worse-eye mean deviation [MD]) to 0.42 (better-eye MD; P < 0.0001 for all). Binocular VA showed stronger correlations with binocular approximations, with r values ranging from 0.65 (worse-eye VA) to 0.80 (binocular summation; P < 0.0001 for all). Correlations between the VAQ and Esterman score were stronger in 7 of 9 subscales (r = -0.14 to -0.25; P < 0.05 for all) than correlations with all 7 binocular approximations. In contrast, correlations between the VAQ and binocular VA (r = -0.07 to -0.21) were weaker in all subscales than those with better-eye, average-eye, and binocular summation of VA (r = -0.12 to -0.25), but not different from worse-eye values. These trends also were found in relevant subscales of the NEI VFQ-25.

CONCLUSIONS

We found limited benefit in binocular testing of VA in the clinical setting as a means of approximating a patient's reported visual functioning. In contrast, we found some benefit in performing binocular VF testing, because the results correlated more closely with reported functioning than binocular approximations.

Gradually Then Suddenly? Decline in Vision-Related Quality of Life as Glaucoma Worsens

Purpose. To evaluate the relationship between self-reported vision-related quality of life (VRQL) and visual field (VF) loss in people from glaucoma clinics. Methods. A postal survey using the National Eye Institute Visual Function Questionnaire (NEI VFQ-25) was administered to people with a range of VF loss identified from a UK hospital-based glaucoma service database. Trends were assessed in a composite score from NEI VFQ-25 against better-eye mean deviation (BEMD) using linear regression and a spline-fitting method that can highlight where a monotonic relationship may have different stages. Results. A total of 636 patients (median [interquartile range] BEMD -2.1 [-5.2, -0.4] dB, median age 70 [60, 77] years) were analysed. Analysis of trends in the data revealed an average patient loses approximately 2 units (out of 100) on NEI VFQ-25 for every loss of 1 dB (BEMD) as VF defects first become bilateral, up to BEMD -5 dB. NEI VFQ-25 deterioration then appears to slow before a more rapid phase of change (4-5 units per 1 dB loss) after BEMD worsens beyond -15 dB. Conclusions. Relationship between decline in VRQL and VF worsening in glaucoma is unlikely to be linear; it more likely has different phases, and these should be further explored in longitudinal studies.

More frequent, more costly? Health economic modelling aspects of monitoring glaucoma patients in England

BACKGROUND

Chronic open angle glaucoma (COAG) is an age-related eye disease causing irreversible loss of visual field (VF). Health service delivery for COAG is challenging given the large number of diagnosed patients requiring lifelong periodic monitoring by hospital eye services. Yet frequent examination better determines disease worsening and speed of VF loss under treatment. We examine the cost-effectiveness of increasing frequency of VF examinations during follow-up using a health economic model.

METHODS

Two different VF monitoring schemes defined as current practice (annual VF testing) and proposed practice (three VF tests per year in the first 2 years after diagnosis) were examined. A purpose written health economic Markov model is used to test the hypothesis that cost effectiveness improves by implementing proposed practice on groups of patients stratified by age and severity of COAG. Further, a new component of the model, estimating costs of visual impairment, was added. Results were derived from a simulated cohort of 10000 patients with quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs) used as main outcome measures.

RESULTS

An ICER of £21,392 per QALY was derived for proposed practice improving to a value of £11,382 once savings for prevented visual impairment was added to the model. Proposed practice was more cost-effective in younger patients. Proposed practice for patients with advanced disease at diagnosis generated ICERs > £60,000 per QALY; these cases would likely be on the most intensive treatment pathway making clinical information on speed of VF loss redundant. Sensitivity analysis indicated results to be robust in relation to hypothetical willingness to pay threshold identified by national guidelines, although greatest uncertainty was allied to estimates of implementation and visual impairment costs.

CONCLUSION

Increasing VF monitoring at the earliest stages of follow-up for COAG appears to be cost-effective depending on reasonable assumptions about implementation costs. Our health economic model highlights benefits of stratifying patients to more or less monitoring based on age and stage of disease at diagnosis; a prospective study is needed to prove these findings. Further, this works highlights gaps in knowledge about long term costs of visual impairment.

Patient-Reported Vision-Related Quality-of-Life Differences between Primary Angle-Closure Glaucoma and Primary Open-Angle Glaucoma

Purpose

To investigate the different impacts on patient-reported vision-related quality of life (pVRQOL) outcomes in patients with primary angle-closure glaucoma(PACG) and primary open-angle glaucoma(POAG).

Methods

Prospective cross-sectional study. PACG and POAG patients who had a best-corrected visual acuity(BCVA) in the better eye equal to or better than 20/60, intraocular pressure controlled at or below 25 mmHg and reliable visual field test were invited to participate. The control group included patients with BCVA in the better eye equal to or better than 20/60 and who did not have major eye disease. A validated Taiwanese version of the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25(T)) was performed to assess pVRQOL. The association between each domain of NEI VFQ-25(T) among 3 groups was determined using multivariable linear regression analysis.

Results

A total of 106 PACG, 186 POAG, and 95 controls were enrolled. In multivariable regression analysis of all three groups(PACG/POAG/controls), compared to POAG, PACG showed a weakly positive association with social functioning (R² = 0.13, β = 0.22, P = 0.04). PACG showed no significantly negative impact on pVRQOL compared to controls. Taking only glaucoma patients into consideration, PACG patients had a higher score on social functioning compared to POAG (R² = 0.16, β = 0.27, P = 0.01). The results of other domains of NEI VFQ-25(T) between the two groups did not differ significantly(p>0.05).

Conclusions

In patients with controlled disease, the impact of PACG and POAG on most domains of NEI VFQ-25(T) were similar, except for better social functioning in PACG compared to POAG.

National Burden of Eye Diseases in Iran, 1990-2010; Findings from the Global Burden of Diseases Study 2010

Purpose:

The disability-adjusted life-years (DALYs) lost due to eye diseases and trends in DALYs in Iran has not been previously reported. The object of this study is to report the burden of eye diseases in Iran and to compare changes from 1990 to 2010 based on age and gender.

Methods:

Data from the Global Burden of Disease Study 2010 (GBD 2010) are used to report DALYs for cataract, refraction/accommodation (functional) disorders, macular degeneration, and glaucoma.

Results:

Cataract, refraction/accommodation (functional) disorders, macular degeneration, and glaucoma were the 84^th, 87^th, 138^th, and 151^st causes of DALY in 1990 and the 89^th, 72^nd, 99^th, and 137^th in 2010, respectively. Cataract accounted for 0.085% of national DALY in 1990 and 0.09% in 2010, refraction/accommodation (functional) disorders accounted for 0.42% in 1990 and 0.47% in 2010, macular degeneration accounted for 0.017% in 1990 and 0.071% in 2010 and glaucoma accounted for 0.0099% in 1990 and 0.025% in 2010. There was a steady increase in DALY with age for each eye disease for both genders and dichotomized for males and females from 1990 to 2010.

Conclusions:

Epidemiologic transition is reflected in major ophthalmic and blinding diseases in the GBD data for Iran. The burden of macular degeneration is rising, followed by glaucoma. The burden of presbyopia affected individuals past their middle age. The burden of cataract manifested as a slower increase that could be attributable to better access to treatment.

Visual impairment and vision-related quality of life in the Early Manifest Glaucoma Trial after 20 years of follow-up

Purpose

To determine the association between vision‐related quality of life (VRQOL) and levels of visual function loss in the Early Manifest Glaucoma Trial (EMGT).

Methods

Two hundred and fifty‐five patients were included in the EMGT between 1993 and 1997 and followed regularly by ophthalmic examinations. A Swedish translation of the National Eye Institute Visual Function Questionnaire 25 (NEI VFQ‐25) was self‐administered at several follow‐up visits until 2014. We analysed the association between Rasch‐calibrated NEI VFQ‐25 scores and visual function in the best eye at the final follow‐up visit.

Results

Ninety‐one per cent (233/255) of all participants completed the NEI VFQ‐25 at least once. In univariate logistic regression analysis, NEI VFQ‐25 scores were modestly associated with visual acuity (VA) (r² = 0.330, p < 0.001), visual field index (VFI) (r² = 0.200, p < 0.001) and perimetric mean deviation (MD) (r² = 0.193, p < 0.001). In multivariate analysis, VA and VFI together accounted for approximately 40% (r² = 0.380) of the NEI VFQ‐25 scores. NEI VFQ‐25 scores were significantly higher for patients with no visual impairment (mean 73 ± 22) than for visually impaired patients (mean 31 ± 15, p < 0.001). VFI worse than 50% or MD worse than −18 dB was significantly associated with low VRQOL scores (p < 0.001).

Conclusions

Our results support the widespread, albeit arbitrary, use of a better‐eye visual field of <50% as an important threshold for a significant reduction in VRQOL.

Visual disability and quality of life in glaucoma patients

Glaucoma is an optic neuropathy that can result in progressive and irreversible vision loss, thereby affecting quality of life (QoL) of patients. Several studies have shown a strong correlation between visual field damage and visual disability in patients with glaucoma, even in the early stages of the disease. Visual impairment due to glaucoma affects normal daily activities required for independent living, such as driving, walking, and reading. There is no generally accepted instrument for assessing quality of life in glaucoma patients; different factors involved in visual disability from the disease are difficult to quantify and not easily standardized. This chapter summarizes recent works from clinical and epidemiological studies, which describe how glaucoma affects the performance of important vision-related activities and QoL.

Ability of Bottle Cap Color to Facilitate Accurate Patient-Physician Communication Regarding Medication Identity in Patients with Glaucoma

PURPOSE

To determine the accuracy of patient-physician communication regarding topical ophthalmic medication use based on bottle cap color, particularly among individuals who may have acquired color vision deficiency from glaucoma.

DESIGN

Cross-sectional, clinical study.

PARTICIPANTS

Patients aged ≥18 years with primary open-angle, primary angle-closure, pseudoexfoliation, or pigment dispersion glaucoma, bilateral visual acuity of ≥20/400, and no concurrent conditions that may affect color vision.

METHODS

A total of 100 patients provided color descriptions of 11 distinct medication bottle caps. Color descriptors were then presented to 3 physicians. Physicians matched each color descriptor to the medication they thought the descriptor was describing.

MAIN OUTCOME MEASURES

Frequency of patient-physician agreement, occurring when all 3 physicians accurately matched the color descriptor to the correct medication. Multivariate regression models evaluated whether patient-physician agreement decreased with degree of better-eye visual field (VF) damage, color descriptor heterogeneity, or color vision deficiency, as determined by the Hardy-Rand-Rittler (HRR) score and Lanthony D15 color confusion index (D15 CCI).

RESULTS

Subjects had a mean age of 69 (±11) years, with VF mean deviation of -4.7 (±6.0) and -10.9 (±8.4) decibels (dB) in the better- and worse-seeing eyes, respectively. Patients produced 102 unique color descriptors to describe the colors of the 11 bottle caps. Among individual patients, the mean number of medications demonstrating agreement was 6.1/11 (55.5%). Agreement was less than 15% for 4 medications (prednisolone acetate [generic], betaxolol HCl [Betoptic; Alcon Laboratories Inc., Fort Worth, TX], brinzolamide/brimonidine [Simbrinza; Alcon Laboratories Inc.], and latanoprost [Xalatan; Pfizer, Inc., New York, NY]). Lower HRR scores and higher D15 CCI (both indicating worse color vision) were associated with greater VF damage (P < 0.001). Extent of color vision deficiency and color descriptor heterogeneity significantly predicted agreement in multivariate models (odds of agreement = 0.90 per 1 point decrement in HRR score, P < 0.001; odds of agreement = 0.30 for medications exhibiting high heterogeneity [≥11 descriptors], P = 0.007).

CONCLUSIONS

Physician understanding of patient medication use based solely on bottle cap color is frequently incorrect, particularly in patients with glaucoma who may have color vision deficiency. Errors based on communication using bottle cap color alone may be common and could lead to confusion and harm.

Severity of vision loss interacts with word-specific features to impact out-loud reading in glaucoma

PURPOSE

To assess the impact of glaucoma-related vision loss on measures of out-loud reading, including time to say individual words, interval time between consecutive words, lexical errors, skipped words, and repetitions.

METHODS

Glaucoma subjects (n = 63) with bilateral visual field loss and glaucoma suspect controls (n = 57) were recorded while reading a standardized passage out loud. A masked evaluator determined the start and end of each recorded word and identified reading errors.

RESULTS

Glaucoma subjects demonstrated longer durations to recite individual words (265 vs. 243 ms, P < 0.001), longer intervals between words (154 vs. 124 ms, P < 0.001), and longer word/post-word interval complexes (the time spanned by the word and the interval following the word; 419 vs. 367 ms, P < 0.001) than controls. In multivariable analyses, each 0.1 decrement in log contrast sensitivity (logCS) was associated with a 15.0 ms longer word/post-interval complex (95% confidence interval [CI] = 9.6-20.4; P < 0.001). Contrast sensitivity was found to significantly interact with word length, word frequency, and word location at the end of a line with regards to word/post-word interval complex duration (P < 0.05 for all). Glaucoma severity was also associated with more lexical errors (Odds ratio = 1.20 for every 0.1 logCS decrement; 95% CI = 1.02-1.39, P < 0.05), but not with more skipped or repeated words.

CONCLUSIONS

Glaucoma patients with greater vision loss make more lexical errors, are slower in reciting longer and less frequently used words, and more slowly transition to new lines of text. These problem areas may require special attention when designing methods to rehabilitate reading in patients with glaucoma.

Longitudinal changes in quality of life and rates of progressive visual field loss in glaucoma patients

PURPOSE

To evaluate the association between longitudinal changes in quality of life (QoL) and rates of progressive visual field loss in glaucoma.

DESIGN

Prospective observational cohort study.

PARTICIPANTS

We recruited 322 eyes of 161 patients with glaucomatous visual field loss from the Diagnostic Innovations Glaucoma Study followed for an average of 3.5±0.7 years.

METHODS

All subjects had National Eye Institute Visual Function Questionnaire (NEI VFQ)-25 performed annually and standard automated perimetry (SAP) at 6-month intervals. Subjects were included if they had a minimum of 2 NEI VFQ-25 and ≥5 SAP during follow-up. Evaluation of rates of visual field change was performed using the mean sensitivity (MS) of the integrated binocular visual field (BVF). Rasch analysis was performed to obtain final scores of disability as measured by the NEI VFQ-25. A joint longitudinal multivariate mixed model was used to investigate the association between change in NEI VFQ-25 Rasch-calibrated scores and change in BVF sensitivity. Potentially confounding socioeconomic and clinical variables also were analyzed.

MAIN OUTCOME MEASURES

The relationship between change in NEI VFQ-25 Rasch-calibrated scores and change in binocular SAP MS.

RESULTS

There was a significant correlation between change in the NEI VFQ-25 Rasch scores during follow-up and change in binocular SAP sensitivity. Each 1-dB change in binocular SAP MS per year was associated with a change of 2.9 units per year in the NEI VFQ-25 Rasch scores during the follow-up period (R(2) = 26%; P<0.001). Eyes with more severe disease at baseline were also more likely to have a decrease in NEI VFQ-25 scores during follow-up (P<0.001). For subjects with the same amount of change in SAP sensitivity, those with shorter follow-up times had larger changes in NEI VFQ-25 scores (P = 0.005). A multivariable model containing baseline and rate of change in binocular MS had an adjusted R(2) of 50% in predicting change in NEI VFQ-25 scores.

CONCLUSIONS

Baseline severity, magnitude, and rates of change in BVF sensitivity were associated with longitudinal changes in QoL of glaucoma patients. Assessment of longitudinal visual field changes may help to identify patients at greater risk for developing disability from the disease.

The relationship between central visual field damage and motor vehicle collisions in primary open-angle glaucoma patients

Purpose

To investigate the relationship between visual field (VF) damage and history of motor vehicle collisions (MVCs) in subjects with primary open-angle glaucoma (POAG).

Methods

MVC history and driving habits were recorded using patient questionnaires in 247 POAG patients. Patients' driving attitudes (carefulness) were estimated using Rasch analysis. The relationship between MVC outcomes and 52 total deviation (TD) values of integrated binocular VF (IVF), better and worse visual acuities (VAs), age and gender was analyzed using principal component analysis and logistic regression.

Results

51 patients had the history of MVCs. Significant difference was observed between patients with and without history of MVCs only for: better VA, a single TD value in the superior-right VF, and the typical distance driven in a week (unpaired t-test, p = 0.002, 0.015 and 0.006, respectively). There was not a significant relationship between MVCs and mean deviation (MD) of IVF (p = 0.41, logistic regression). None of the principal components were significantly correlated with MVC outcome (p>0.05, polynomial logistic regression analysis). There was a significant relationship between IVF MD and Rasch derived Person parameter (R² = 0.023, p = 0.0095). There was also a significant positive relationship between MVCs and the distance driven in a week (p = 0.005, logistic regression).

Conclusions

In this study of POAG patients, MVCs were not related to central binocular VF damage. These results suggest the relationship between visual function and driving is not straightforward, and careful consideration should be given when predicting patients' driving ability using their VF.

Glaucoma and associated visual acuity and field loss significantly affect glaucoma-specific psychosocial functioning

OBJECTIVE

To examine the impact of glaucoma and visual acuity (VA) and visual field (VF) losses on psychosocial functioning (PF).

DESIGN

Cross-sectional study.

PARTICIPANTS

We compared PF between 192 participants with bilateral glaucoma with VA or VF losses and 40 controls from a tertiary eye hospital clinic in Singapore.

METHODS

Glaucoma was defined using the Hodapp-Anderson-Parish criteria. Four psychosocial outcomes of the Glaucoma Quality of Life 36 questionnaire were psychometrically assessed using Rasch analysis. Multivariate regression was performed to determine the independent impact of glaucoma and VA and VF losses on PF. The impact of VA and VF on PF were evaluated by restricted cubic spline analysis.

MAIN OUTCOME MEASURES

Anxiety, self-image, psychological well-being, and confidence in health care.

RESULTS

The mean age of participants was 66.2±11.0 years, and 63% were male. In the better eye, VA and mean deviation were Snellen 20/25 and -8.89±6.52 dB, respectively. In multivariate models, glaucoma patients had 63.0% greater anxiety (95% confidence interval [CI], -66.0% to -61.2%; P<0.001), 71.0% lower self-image (95% CI, -74.1% to -68.5%; P<0.001), 38.3% less psychological well-being (95% CI, -37.4% to -39.0%; P<0.001), and 32.4% reduced confidence in health care than patients without glaucoma. The worst VA and VF categories had the most reduced PF (range, 26.0% to 81.5%; P<0.001 for all associations) compared with controls. With worsening VA, there was a linear increase in anxiety (P=0.009) and decrease in self-image (P=0.005). With worsening VF from 0 to -12.1 dB (P=0.003), anxiety increased before plateauing. Self-image decreased as VF worsened from 0 to -10 dB (P<0.001), and confidence in health care decreased when VF worsened from 0 to -9.3 dB (P=0.008). However, self-image and confidence in health care actually improved at greater levels of VF loss beyond these thresholds.

CONCLUSION

Glaucoma negatively affects PF. Early stage glaucoma with mild VF loss adversely affects anxiety, self-image, and confidence in health care. As VA worsens in advanced glaucoma, anxiety further increases and self-image deteriorates. Ophthalmologists and glaucoma patients need to be aware that both VA and VF losses at different stages of glaucoma negatively impact PF.

Reading ability and reading engagement in older adults with glaucoma

PURPOSE

We evaluated the impact of glaucoma-related vision loss on reading ability and reading engagement in 10 reading activities.

METHODS

A total of 63 glaucoma patients and 59 glaucoma suspect controls self-rated their level of reading difficulty for 10 reading items, and responses were analyzed using Rasch analysis to determine reading ability. Reading engagement was assessed by asking subjects to report the number of days per week they engaged in each reading activity. Reading restriction was determined as a decrement in engagement.

RESULTS

Glaucoma subjects more often described greater reading difficulty than controls for all tasks except puzzles (P < 0.05). The most difficult reading tasks involved puzzles, books, and finances, while the least difficult reading tasks involved notes, bills, and mail. In multivariable weighted least squares regression models of Rasch-estimated person measures of reading ability, less reading ability was found for glaucoma patients compared to controls (β = -1.60 logits, P < 0.001). Among glaucoma patients, less reading ability was associated with more severe visual field (VF) loss (β = -0.68 logits per 5-dB decrement in better-eye VF mean deviation [MD], P < 0.001) and contrast sensitivity (β = -0.76 logits per 0.1-unit lower log CS, P < 0.001). Each 5-dB decrement in the better-eye VF MD was associated with book reading on 18% fewer days (P = 0.003) and newspaper reading on 10% fewer days (P = 0.008). No statistically significant reading restriction was observed for other reading activities (P > 0.05).

CONCLUSIONS

Glaucoma patients have less reading ability and engage less in a variety of different reading activities, particularly those requiring sustained reading. Future work should evaluate the mechanisms underlying reading disability in glaucoma to determine how patients can maintain reading ability and engagement.

Glaucomatous visual field loss associated with less travel from home

PURPOSE

To determine the association between glaucoma and travel away from home.

METHODS

Fifty-nine glaucoma suspect controls with normal vision and 80 glaucoma subjects with bilateral visual field (VF) loss wore a cellular tracking device during 1 week of normal activity. Location data were used to evaluate the number of daily excursions away from home as well as daily time spent away from home.

RESULTS

Control and glaucoma subjects were similar in age, race, sex, employment, driving support, cognitive ability, mood, and comorbid illness (p > 0.1 for all). Better-eye VF mean deviation (MD) averaged 0.0 decibels (dB) in controls and -11.1 dB in glaucoma subjects. In multivariable models, glaucoma was associated with fewer daily excursions (β = -0.20; 95% confidence interval [95% CI], -0.38 to -0.02) and a greater likelihood of not leaving home on a given day (odds ratio [OR], 1.82; 95% CI, 1.05 to 3.06). Each 5-dB decrement in the better-eye VF MD was associated with fewer daily excursions (β = -0.06; 95% CI, -0.11 to -0.01) and a greater chance of not leaving home on a given day (OR, 1.24; 95% CI, 1.04 to 1.47). Time spent away from home did not significantly differ between the glaucoma subjects and suspects (p = 0.18). However, each 5-dB decrement in the better-eye MD was associated with 6% less time away (95% CI, -12 to -1%).

CONCLUSIONS

Individuals with glaucoma, particularly those with greater VF loss, are more home bound and travel away from home less than individuals with normal vision. Because being confined to the home environment may have detrimental effects on fitness and health, individuals with glaucoma should be considered for interventions such as orientation and mobility training to encourage safe travel away from home.