Diffuse Macular Damage in Mild to Moderate Glaucoma Is Associated With Decreased Visual Function Scores Under Low Luminance Conditions

Improving glaucoma staging in clinical practice by combining the ICD-10 glaucoma severity classification system and optical coherence tomography

OBJECTIVE

The International Classification of Disease, 10th revision (ICD-10) codes used for glaucoma severity classification are based on the 24-2 visual-field (VF) test. This study aim was to assess the added value of providing clinicians with optical coherence tomography (OCT) data, in addition to functional data, for glaucoma staging in clinical practice.

EXPOSURE

Disease classification was determined for 54 glaucoma eyes, according to the principles of the ICD-10 guidelines. Eyes were independently graded in a masked fashion using the 24-2 VF test and 10-2 VF test, with and without OCT information. The reference standard (RS) for severity was determined using a previously published automated structure-function topographic agreement for glaucomatous damage using all available information.

RESULTS

The RS classified eyes as mild, moderate and advanced in 3, 16 and 35 cases, respectively. Individual and combined 24-2 and 10-2 based gradings were significantly different from the RS (all P < 0.005), with Kappa agreements of 0.26, 0.45 and 0.42 respectively (P < 0.001). Classifications using OCT combined with either of the VF were not-significantly different from the RS (P > 0.3) with Kappa agreements of 0.56 and 0.57 respectively (P < 0.001). Combining 24-2 with OCT had less severity overestimations while 10-2 with OCT had fewer underestimations.

CONCLUSION

Combining OCT and VF data provides better staging of glaucoma severity than VF data alone. The 24-2 and OCT combination seems most appropriate given the high concordance with the RS and less overestimation of severity. Incorporating structural information into disease stages allows clinicians to set more appropriate severity-based treatment targets for individual patients.

MNREAD Reading Vision in Adults With Glaucoma Under Mesopic and Photopic Conditions

Purpose

Despite good photopic visual acuity, glaucoma patients report difficulty performing daily activities under dim light such as reading. Here we investigated the impact of mesopic lighting conditions on reading vision of glaucoma patients.

Methods

The study design included 39 patients with glaucoma and 40 healthy controls. Reading vision was assessed with MNREAD charts under mesopic (2 cd/m2) and photopic (220 cd/m2) conditions. Four reading indexes: maximum reading speed (MRS), critical print size (CPS), reading acuity (RA), and reading accessibility index (ACC) were obtained from the MNREAD test yielding a plot of reading speed versus print size.

Results

Compared to photopic conditions, reading vision of both healthy controls and glaucoma patients significantly decreased under mesopic conditions (P < 0.05). For glaucoma patients (85% with mild or moderate glaucoma), MRS and ACC decreased by six words per minute and 0.1, respectively under mesopic conditions; CPS and RA increased by 0.25 and 0.18 logMAR, respectively. Moreover, under both photopic and mesopic conditions, reading vision of glaucoma patients was significantly worse than that of healthy controls, but the difference was greater under mesopic conditions (P < 0.05) even after controlling for age and visual acuity.

Conclusions

Mesopic conditions make reading more challenging for both healthy controls and glaucoma patients. However, reading in dim light appears to be more burdensome for glaucoma patients. Mesopic reading tests mediated by both cone and rod photoreceptor systems likely provide a more sensitive and comprehensive assessment of a patient's reading impairment than testing under photopic conditions.

Effect of low luminance on face recognition in adults with central and peripheral vision loss

PURPOSE

To investigate the effect of low luminance on face recognition, specifically facial identity discrimination (FID) and facial expression recognition (FER), in adults with central vision loss (CVL) and peripheral vision loss (PVL) and to explore the association between clinical vision measures and low luminance FID and FER.

METHODS

Participants included 33 adults with CVL, 17 with PVL and 20 controls. FID and FER were assessed under photopic and low luminance conditions. For the FID task, 12 sets of three faces with neutral expressions were presented and participants asked to indicate the odd-face-out. For FER, 12 single faces were presented and participants asked to name the expression (neutral, happy or angry). Photopic and low luminance visual acuity (VA) and contrast sensitivity (CS) were recorded for all participants and for the PVL group, Humphrey Field Analyzer (HFA) 24-2 mean deviation (MD).

RESULTS

FID accuracy in CVL, and to a lesser extent PVL, was reduced under low compared with photopic luminance (mean reduction 20% and 8% respectively; p < 0.001). FER accuracy was reduced only in CVL (mean reduction 25%; p < 0.001). For both CVL and PVL, low luminance and photopic VA and CS were moderately to strongly correlated with low luminance FID (ρ = 0.61-0.77, p < 0.05). For PVL, better eye HFA 24-2 MD was moderately correlated with low luminance FID (ρ = 0.54, p = 0.02). Results were similar for low luminance FER. Together, photopic VA and CS explained 75% of the variance in low luminance FID, and photopic VA explained 61% of the variance in low luminance FER. Low luminance vision measures explained little additional variance.

CONCLUSION

Low luminance significantly reduced face recognition, particularly for adults with CVL. Worse VA and CS were associated with reduced face recognition. Clinically, photopic VA is a good predictor of face recognition under low luminance conditions.

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

PURPOSE

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

DESIGN

Observational study.

PARTICIPANTS

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

METHODS

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

MAIN OUTCOME MEASURES

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

RESULTS

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

CONCLUSIONS

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

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

The ICD-10 Glaucoma Severity Score Underestimates the Extent of Glaucomatous Optic Nerve Damage

PURPOSE

To evaluate the International Classification of Disease, Tenth Revision (ICD-10) codes used for glaucoma severity classification, which are based on the location of visual field (VF) defects; given the known poor sensitivity of the 24-2 visual field test to early disease and macular damage, we hypothesized that the ICD-10 codes would not accurately reflect the extent of glaucomatous damage.

DESIGN

Retrospective validity and reliability analysis.

METHODS

We evaluated 80 eyes with glaucomatous optic neuropathy (GON). Masked reviewers assigned an ICD-10 severity grade based on 24-2 VF. Two additional masked examiners determined the presence of optical coherence tomography (OCT) structural damage in each hemifield and/or central 5 degrees to define an OCT-based equivalent ICD-10 classification.

RESULTS

A total of 80 eyes with GON were classified as mild, moderate and advanced in 15, 23, and 42 cases, respectively, based on the 24-2 VF, and in 6, 7, and 67 cases, respectively, based on OCT. The OCT classifications were more severe in 29 of 80 cases (36%). In 33 cases (41.3%), macular damage detected by OCT was missed by the 24-2. In 4 of 80 cases (5%), the VF overestimated the severity, likely due to variability of the 24-2 test.

CONCLUSIONS

The ICD-10 system relies solely on damage seen on the 24-2 and as provides a 24-2 functional score rather than a "glaucoma" severity score. OCT revealed wide variation of damage across grades, with a significant proportion of the eyes showing macular structural damage missed with the 24-2 VF. Adding OCT information to the ICD-10 system would help it to more accurately reflect the extent of glaucomatous damage.

Daily Patterns of Accelerometer-Measured Movement Behaviors in Glaucoma Patients: Insights From UK Biobank Participants

PURPOSE

The purpose of this study is to compare daily patterns of accelerometer-measured movement behaviors between glaucoma patients and those without glaucoma.

METHODS

From 2013 to 2015, 106,053 UK Biobank participants took part in a 7-day accelerometer test. Based on established algorithms, continuous accelerometer data were classified into 4 movement behaviors: moderate to vigorous physical activity (MVPA), light physical activity, sedentary behaviors, and sleep. Glaucoma and other covariates were defined according to baseline assessments and inpatient diagnosis records. Negative binomial regression models were used to compare daily patterns of movement behaviors between glaucoma patients and those without glaucoma.

RESULTS

Accelerometer data from 1262 glaucoma patients and 81,551 participants without glaucoma were included. Compared with participants without glaucoma, glaucoma patients spent 4.7% less time on MVPA in multivariable models [mean=28.3 vs 31.4 min/d; incidence-rate ratio (IRR) 0.953, 95% confidence interval (CI): 0.910-0.998; P=0.044], which was mainly attributed to the decreased MVPA time during 18:00-23:59 (IRR=0.863, Bonferroni-corrected 95% CI: 0.768-0.970; P=0.002). Subgroup analyses indicated that compared with those with normal body mass index, the decreased MVPA time was more pronounced in participants with overweight and obesity (IRR=0.912, Bonferroni-corrected 95% CI: 0.851-0.978; P for interaction=0.007). No significant association was found between glaucoma and time spent on other movement behaviors including light physical activity, sedentary behaviors, and sleep.

CONCLUSIONS

Daily patterns of movement behaviors were significantly changed in glaucoma patients. Compared with those without glaucoma, glaucoma patients spent less time on MVPA, especially in the evening.

Altered eye movements during reading under degraded viewing conditions: Background luminance, text blur, and text contrast

Degraded viewing conditions caused by either natural environments or visual disorders lead to slow reading. Here, we systematically investigated how eye movement patterns during reading are affected by degraded viewing conditions in terms of spatial resolution, contrast, and background luminance. Using a high-speed eye tracker, binocular eye movements were obtained from 14 young normally sighted adults. Images of text passages were manipulated with varying degrees of background luminance (1.3-265 cd/m2), text blur (severe blur to no blur), or text contrast (2.6%-100%). We analyzed changes in key eye movement features, such as saccades, microsaccades, regressive saccades, fixations, and return-sweeps across different viewing conditions. No significant changes were observed for the range of tested background luminance values. However, with increasing text blur and decreasing text contrast, we observed a significant decrease in saccade amplitude and velocity, as well as a significant increase in fixation duration, number of fixations, proportion of regressive saccades, microsaccade rate, and duration of return-sweeps. Among all, saccade amplitude, fixation duration, and proportion of regressive saccades turned out to be the most significant contributors to reading speed, together accounting for 90% of variance in reading speed. Our results together showed that, when presented with degraded viewing conditions, the patterns of eye movements during reading were altered accordingly. These findings may suggest that the seemingly deviated eye movements observed in individuals with visual impairments may be in part resulting from active and optimal information acquisition strategies operated when visual sensory input becomes substantially deprived.

Foveal crowding appears to be robust to normal aging and glaucoma unlike parafoveal and peripheral crowding

Visual crowding is the inability to recognize a target object in clutter. Previous studies have shown an increase in crowding in both parafoveal and peripheral vision in normal aging and glaucoma. Here, we ask whether there is any increase in foveal crowding in both normal aging and glaucomatous vision. Twenty-four patients with glaucoma and 24 age-matched normally sighted controls (mean age = 65 ± 7 vs. 60 ± 8 years old) participated in this study. For each subject, we measured the extent of foveal crowding using Pelli's foveal crowding paradigm (2016). We found that the average crowding zone was 0.061 degrees for glaucoma and 0.056 degrees for age-matched normal vision, respectively. These values fall into the range of foveal crowding zones (0.0125 degrees to 0.1 degrees) observed in young normal vision. We, however, did not find any evidence supporting increased foveal crowding in glaucoma (p = 0.375), at least in the early to moderate stages of glaucoma. In the light of previous studies on foveal crowding in normal young vision, we did not find any evidence supporting age-related changes in foveal crowding. Even if there is any, the effect appears to be rather inconsequential. Taken together, our findings suggest unlike parafoveal or peripheral crowding (2 degrees, 4 degrees, 8 degrees, and 10 degrees eccentricities), foveal crowding (<0.25 degrees eccentricity) appears to be less vulnerable to normal aging or moderate glaucomatous damage.

The Role of Intraocular Pressure and Systemic Hypertension in the Progression of Glaucomatous Damage to the Macula

PRCIS

Macular structural and functional parameters were better correlated with pressure-dependent glaucomatous damage than conventional parameters. Self-reported systemic hypertension (HTN) was not associated with structural or functional progression in this cohort.

PURPOSE

The aim was to examine the relationships between intraocular pressure (IOP), systemic HTN, and glaucoma progression using structural testing with optical coherence tomography (OCT) and functional testing with visual field (VF).

PATIENTS AND METHODS

A total of 191 eyes of 119 patients enrolled in a prospective, longitudinal study (Structural and Functional Progression of Glaucomatous Damage to the Macula study) with a diagnosis of glaucoma were analyzed. Patients were tested with 10-2 and 24-2 VF and spectral-domain OCT obtained at 4 to 6 month intervals. IOP from each visit was collected. Self-reported diagnoses of HTN were reported in 72 eyes (37%) in the patients included. Linear mixed effects regression was used to test the relationship between summary statistics from VF and OCT and HTN diagnosis. The goodness-of-fit of relationships was assessed with Bayesian information criterion.

RESULTS

Mean follow-up IOP was most associated with the following OCT parameters: global macula ganglion cell layer (GCL), inferior macula GCL, mean macular vulnerability zone GCL, and mean less vulnerable zone macula GCL, and with the following VF parameters: 10-2 PSD and 10-2 MD. There was no significant difference in rates of progression between HTN and non-HTN patients for any OCT or VF parameter. Models with the best goodness-of-fit for the relationship between HTN and progression were the same as those observed for IOP.

CONCLUSION

Macular structural and functional parameters are more sensitive to IOP in terms of glaucomatous progression when compared with more conventional parameters. While HTN was not significantly associated with progression using any parameter, macular structural and functional parameters had a better goodness-of-fit to model progression and may be useful as endpoints.

Evaluation of the association between macular damage and disability glare in patients with advanced glaucoma

PURPOSE

This study aimed to investigate the factors associated with disability glare in patients with advanced glaucoma and evaluate the impact of disability glare on the vision-related quality of life.

METHODS

We prospectively studied 225 eyes (225 patients) with advanced glaucoma. The visual function was evaluated using the 10-2 and 24-2 Humphrey visual field (VF) (Dublin, California) and contrast sensitivity test. Structural parameters were obtained using RTVue optical coherence tomography and angiography (Fremont, California). Significant loss of macular vessel density (mVD) was defined as VD < 30%. Each participant completed the National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ-25) and questions regarding subjective symptoms of glare.

RESULTS

Fifty-six patients (24.9%) experienced glare and had a lower NEI-VFQ-25 composite score (P = 0.017). The average retinal nerve fiber layer and ganglion cell complex thickness and mean deviation (MD) in the 24-2 VF test were not associated with glare. Significant superior or inferior mVD loss (P < 0.001; odds ratio [OR], 3.45; and 95% confidence interval [CI], 1.83-6.55), lower logarithmic contrast sensitivity at 0.75 cycles/degree (P < 0.001; OR, 0.27; and 95% CI, 0.13-0.56), and worse MD in the 10-2 VF test (P < 0.001; OR, 0.93; and 95% CI, 0.89-0.97) showed an association with glare.

CONCLUSION

In advanced glaucoma, central VF defect and mVD loss are associated with disability glare, which negatively impacts vision-related quality of life.

Prediction of 10-2 Visual Field Loss Using Optical Coherence Tomography and 24-2 Visual Field Data

PRECIS

Using standard glaucoma structural and functional tests, clinicians accurately predicted the presence/absence of 10-2 glaucomatous visual field (VF) loss in 90% of the eyes in this study.

PURPOSE

To investigate how well clinicians with variable experience can predict the presence and location of 10-2 VF loss using structural and functional data that are routinely obtained for glaucoma assessment.

METHODS

Within a test set of 416 eyes (210 subjects) who were diagnosed glaucoma suspect or primary open-angle glaucoma (with most eyes having mild disease), 6 clinicians were asked to predict the presence and hemispheric location of 10-2 VF loss using 24-2 VF and spectral-domain optical coherence tomography structural data. Prediction accuracies were calculated for each clinician and compared using the weighted κ-statistic. Receiver operating characteristic analyses were used to evaluate models for predicting 10-2 VF loss.

RESULTS

Among the 6 clinicians, mean (range) accuracy, false negatives, and false positives for predicting presence/absence of 10-2 VF loss were 90% (87% to 92%), 4.7% (2.4% to 7.0%), and 5.4% (1.7% to 7.5%) respectively. The mean (range) weighted κ-statistic was 0.75 (0.64 to 0.83), suggesting good or very good inter-rater agreement between examiners. Mean accuracy for correctly predicting hemispheric location was 73% (range, 65% to 82%) with the most common error occurring in eyes with both superior and inferior 10-2 VF defects in which one hemisphere was correctly identified but the other missed.

CONCLUSIONS

In this study, the presence/absence of 10-2 glaucomatous VF loss was highly predictable using standard functional and structural clinical metrics. These findings suggest that 10-2 VF testing is not needed to reliably recognize and confirm central VF involvement in most eyes with glaucoma. Whether error related to identifying second hemisphere involvement in 10-2 VF loss is important requires further study.

Impact of low luminance conditions on quality of life for the visually impaired: development of the Low Luminance Questionnaire Japanese version

PURPOSE

This study aimed to develop a Japanese version of the Low Luminance Questionnaire (LLQ-J) and to evaluate its reliability and validity.

STUDY DESIGN

Cross-sectional study.

METHODS

LLQ-J was developed by standardized methods. A total of 101 patients comprising 55 with age-related macular degeneration, 25 with glaucoma, 15 with regressed proliferative diabetic retinopathy, and 6 with retinitis pigmentosa were included in this study. The patients completed the LLQ-J and Japanese version of the visual function Questionnaire-25 (VFQ-25). Using the LLQ-J data, floor and ceiling effects were computed. To examine internal consistency, some patients completed the LLQ-J a second time 2-4 weeks later and the data were analyzed for Cronbach's alpha and intra-class correlation coefficients (ICCs). Best-corrected visual acuity (BCVA) and low luminance visual acuity (LLVA) were measured, and low-luminance deficit (LLD) was calculated. Criterion validity was also tested.

RESULTS

No ceiling or floor effects were present in the LLQ-J data. Cronbach's alfa was 0.88, and ICCs were higher than 0.70 for all subscales. Moderate to high correlation was observed between LLQ-J and VFQ-25 (p < 0.01), confirming concurrent validity. "General dim lighting" and "Peripheral vision" were significantly associated with LLVA in the better eye (p < 0.05). "Mobility", "General dim lighting" and "Peripheral vision" were significantly associated with LLD (p < 0.05). "Emotional distress" was significantly associated with BCVA in the worse eye (p < 0.05). No subscales were associated with BCVA of the better eye.

CONCLUSIONS

The LLQ-J is a valid and reliable questionnaire for assessing QOL under low luminance conditions.

An Evaluation of a New 24-2 Metric for Detecting Early Central Glaucomatous Damage

PURPOSE

We sought to test the hypothesis that a recently proposed pattern standard deviation (PSD) metric, based upon the 24-2 visual field (VF) test, as well as the PSD of the 10-2 VF, will miss central glaucomatous damage confirmed with an objective structure-function method.

DESIGN

Cross-sectional study.

METHODS

A glaucoma (G) group (70 eyes/patients) diagnosed with glaucoma and a 24-2 mean deviation better than -6 dB and a healthy (H) group (45 eyes/patients) had 24-2 and 10-2 VFs and optical coherence tomography (OCT) scans twice within 4 weeks. The PSD(C24-2), based upon the central 12 points of the 24-2, was compared with the PSD(10-2). To evaluate central damage (CD) in G eyes with normal PSD(C24-2) values, a post hoc analysis was combined with a CD reference standard (CD-RS), which was based upon an objective, topographic comparison between abnormal points on the 10-2 VF and OCT probability maps.

RESULTS

The 115 PSD(C24-2) and PSD(10-2) values were significantly correlated (Spearman correclation coefficient: rho = 0.55; P < .001) and the number of G eyes (19) identified as abnormal by the PSD(C24-2) was not significantly different from the number (22) identified by the PSD(10-2) (P = .15). However, based upon the CD-RS, 44 of 70 G eyes were classified as abnormal. The PSD(C24-2) missed 27 (61%) of these 44 eyes, and the PSD(10-2) missed 23 (52%) of these eyes. Post hoc analysis revealed clear CD in most of these eyes.

CONCLUSION

Neither the PSD(C24-2) nor the PSD(10-2) metric is good measure of early CD. Instead we recommend a topographic approach based upon OCT probability maps and a 10-2 VF.

Lighting conditions and perceived visual function in ophthalmic conditions

PURPOSE

To determine the influence of different lighting conditions on perceived visual function in patients of different age, gender, race, and in various ophthalmic diseases.

METHODS

A prospective study. A survey given to patients seen in general ophthalmic and retina clinics. Patients were asked four questions: Is your vision better, worse, or the same in (1) bright light vs dim light, (2) indoors or outdoors, (3) beginning or end of the day, and (4) sunny or cloudy day? Parameters tested were age, race, gender, visual acuity, and a variety of ophthalmic conditions. Multivariable models for each question were fit using multinomial regression. Association was considered significant if p < 0.05.

RESULTS

A total of 722 patients were enrolled in the study. Patients with lower vision (LogMAR ≥ 0.3) were more likely to indicate they either had better vision indoors or outdoors compared with better vision patients (LogMAR < 0.1). Patients with pseudophakia were also more likely to indicate they had better vision on a cloudy day (OR = 1.9). White patients had double the odds of selecting bright light compared with others. Males were less likely than females to indicate better vision indoors (OR = 0.62). There were no significant associations with age-related macular degeneration (AMD) in the multivariable model.

CONCLUSIONS

Most patients did not note any difference in lighting conditions, and although there is explanatory rational for some of the findings in this study, those questions concerning lighting conditions or time of day are not useful for screening of disease. Gender and ethnicity were found to have associations with lighting preferences which needs to be further studied.

Improving the Detection of Glaucoma and Its Progression: A Topographical Approach

Glaucoma is typically defined as a progressive optic neuropathy characterized by a specific (arcuate) pattern of visual field (VF) and anatomic changes. Therefore, we should be comparing arcuate patterns of damage seen on VFs with those seen on optical coherence tomography (OCT) maps. Instead, clinicians often use summary metrics such as VF pattern standard deviation, OCT retinal nerve fiber (RNF) global thickness, etc. There are 2 major impediments to topographically comparing patterns of damage on VF and OCT maps. First, until recently, it was not easy to make these comparisons with commercial reports. While recent reports do make it easier to compare VF and OCT maps, they have shortcomings. In particular, the 24-2 VF covers a larger retinal region than the commercial OCT scans, and, further, it is not easy to understand the topographical relationship among the different maps/plots within the current OCT reports. Here we show how a model of RNF bundles can overcome these problems. The second major impediment is the lack of a quantitative, and automated, method for comparing patterns of damage seen on VF and OCT maps. However, it is now possible to objectively and automatically quantify this agreement. Together, the RNF bundle model and the automated structure-function method should improve the power of topographical methods for detecting glaucoma and its progression. This should prove useful in clinical studies and trials, as well as for training and validating artificial intelligence/deep learning approaches for these purposes.