The Relative Odds of Progressing by Structural and Functional Tests in Glaucoma.

PurposeThe purpose of this study was to evaluate the effect of disease severity and number of tests acquired during follow-up on the relative odds of identifying progression by structural or functional tests in glaucoma.MethodsThis was an observational cohort study involving 462 eyes of 305 patients with glaucoma and 62 eyes of 49 healthy subjects. Glaucoma patients and healthy subjects were followed for an average of 3.6 ± 0.9 and 3.8 ± 0.9 years, with a median (interquantile range) of 8 (6-9) and 7 (6-8) visits, respectively. At each visit, subjects underwent visual field assessment with standard automated perimetry (SAP) and retinal nerve fiber layer (RNFL) evaluation by spectral-domain optical coherence tomography (SD-OCT). Slopes of change in SAP mean sensitivity and OCT RNFL thickness over time were estimated by linear regression using progressively cumulative visits over time. Cutoff values for age-related expected rates of change for each test were obtained from the healthy group. Progression by SD-OCT and/or SAP was determined if the slope of change was statistically significant and also lower (faster) than the fifth percentile cutoff calculated from the healthy group. A generalized estimating equation logistic regression model was used to evaluate the relative odds of progressing by OCT versus SAP in glaucoma eyes.ResultsEyes with less severe disease at baseline had a higher chance of being detected as progressing by SD-OCT but not by SAP, whereas an increase in disease severity at baseline increased the chance that the eye would be detected as progressing by SAP but not SD-OCT. Each 1 dB higher MD was associated with a 5% increase in the odds of detecting progression by SD-OCT versus SAP (odds ratio = 1.05 per 1 dB; 95% confidence interval: 1.01-1.09; P = 0.005).ConclusionsThe ability to detect glaucoma progression by SAP versus SD-OCT is significantly influenced by the stage of disease. Our results may provide useful information for guiding clinicians on the relative utility of these tests for detecting change throughout the disease continuum

Estimated rates of retinal ganglion cell loss in glaucomatous eyes with and without optic disc hemorrhages.

PurposeTo evaluate whether optic disc hemorrhages are associated with faster rates of estimated retinal ganglion cell (RGC) loss in glaucoma.MethodsA longitudinal observational cohort study of 222 eyes of 122 patients with glaucoma recruited from the Diagnostic Innovations Glaucoma Study (DIGS) followed for an average of 3.74±0.85 years. All subjects had optical coherence tomography and standard automated perimetry during follow up. Optic disc hemorrhages were detected by masked evaluation of stereophotographs. Rates of change in estimated numbers of RGCs were determined using a previously described method. A random coefficients model was used to investigate the relationship between disc hemorrhages and rates of change in estimated RGC counts over time.Results19 eyes of 18 subjects had at least one disc hemorrhage during follow up. At baseline, average estimated RGC counts in eyes with and without disc hemorrhages were 677,994 cells and 682,021 cells, respectively (P = 0.929). Eyes with optic disc hemorrhages during follow-up had significantly faster rates of estimated RGC loss than eyes without disc hemorrhages (22,233 cells/year versus 10,704 cells/year, P = 0.020). The effect of disc hemorrhages on the rates of estimated RGC loss remained significant after adjusting for confounding variables.ConclusionEyes with disc hemorrhages showed faster rates of RGC loss compared to eyes without disc hemorrhages. These results provide further evidence that disc hemorrhages should be considered as an indicator of increased risk for faster neural loss in glaucoma

Rates of Retinal Nerve Fiber Layer Loss in Contralateral Eyes of Glaucoma Patients with Unilateral Progression by Conventional Methods.

PurposeTo determine whether progressive retinal nerve fiber layer (RNFL) loss occurs in the contralateral eye of patients with glaucoma showing unilateral progression according to conventional diagnostic methods.DesignProspective, longitudinal, observational cohort study.ParticipantsThree hundred forty-six eyes of 173 patients (118 eyes with glaucoma and 228 eyes with suspect glaucoma at baseline) followed up for an average of 3.5±0.7 years.MethodsAll subjects underwent standard automated perimetry (SAP; Humphrey Field Analyzer; Carl Zeiss Meditec, Dublin, CA) and spectral-domain (SD) optical coherence tomography (OCT; Spectralis; Heidelberg Engineering, Inc., Carlsbad, CA) in both eyes at 6-month intervals. Eyes were determined as progressing by conventional methods if there was progression on masked grading of optic disc stereophotographs or SAP Guided Progression Analysis (GPA; Carl Zeiss Meditec; "likely progression"). Rates of change in SD OCT average RNFL thickness were obtained using a linear mixed effects model. Rate of global loss was calculated using a random coefficient model and compared for nonprogressing patients, progressing eyes, and fellow eyes of unilateral progressing patients.Main outcomes measuresRate of change in global RNFL thickness.ResultsThirty-nine subjects showed evidence of unilateral progression by GPA, disc photographs, or both during follow-up. Mean ± standard error rate of RNFL loss in eyes progressing by conventional methods was -0.89±0.22 μm/year (P<0.001). The contralateral eyes of these subjects also showed significant loss of RNFL over time (-1.00±0.20 μm/year; P<0.001). One hundred thirty-four subjects did not show progression by conventional methods in either eye. These eyes also showed a significant decline over time in average RNFL thickness (-0.71±0.09 μm/year; P<0.001); however, the rate of change in these eyes was slower than that of the contralateral eye of patients showing unilateral progression (P<0.001).ConclusionsLoss of RNFL thickness was seen in a substantial number of contralateral eyes of glaucoma patients showing unilateral progression by conventional methods. These findings indicate that assessment of RNFL thickness by SD OCT may show progressive glaucomatous damage that is not detected by visual fields or optic disc stereophotography

Rates of Retinal Nerve Fiber Layer Loss in Contralateral Eyes of Glaucoma Patients with Unilateral Progression by Conventional Methods.

PurposeTo determine whether progressive retinal nerve fiber layer (RNFL) loss occurs in the contralateral eye of patients with glaucoma showing unilateral progression according to conventional diagnostic methods.DesignProspective, longitudinal, observational cohort study.ParticipantsThree hundred forty-six eyes of 173 patients (118 eyes with glaucoma and 228 eyes with suspect glaucoma at baseline) followed up for an average of 3.5±0.7 years.MethodsAll subjects underwent standard automated perimetry (SAP; Humphrey Field Analyzer; Carl Zeiss Meditec, Dublin, CA) and spectral-domain (SD) optical coherence tomography (OCT; Spectralis; Heidelberg Engineering, Inc., Carlsbad, CA) in both eyes at 6-month intervals. Eyes were determined as progressing by conventional methods if there was progression on masked grading of optic disc stereophotographs or SAP Guided Progression Analysis (GPA; Carl Zeiss Meditec; "likely progression"). Rates of change in SD OCT average RNFL thickness were obtained using a linear mixed effects model. Rate of global loss was calculated using a random coefficient model and compared for nonprogressing patients, progressing eyes, and fellow eyes of unilateral progressing patients.Main outcomes measuresRate of change in global RNFL thickness.ResultsThirty-nine subjects showed evidence of unilateral progression by GPA, disc photographs, or both during follow-up. Mean ± standard error rate of RNFL loss in eyes progressing by conventional methods was -0.89±0.22 μm/year (P<0.001). The contralateral eyes of these subjects also showed significant loss of RNFL over time (-1.00±0.20 μm/year; P<0.001). One hundred thirty-four subjects did not show progression by conventional methods in either eye. These eyes also showed a significant decline over time in average RNFL thickness (-0.71±0.09 μm/year; P<0.001); however, the rate of change in these eyes was slower than that of the contralateral eye of patients showing unilateral progression (P<0.001).ConclusionsLoss of RNFL thickness was seen in a substantial number of contralateral eyes of glaucoma patients showing unilateral progression by conventional methods. These findings indicate that assessment of RNFL thickness by SD OCT may show progressive glaucomatous damage that is not detected by visual fields or optic disc stereophotography

Frequency Doubling Technology Perimetry and Changes in Quality of Life of Glaucoma Patients: A Longitudinal Study.

PurposeTo evaluate the relationship between rates of change on frequency doubling technology (FDT) perimetry and longitudinal changes in quality of life (QoL) of glaucoma patients.DesignProspective observational cohort study.MethodsOne hundred fifty-two subjects (127 glaucoma and 25 healthy) were followed for an average of 3.2 ± 1.1 years. All subjects were evaluated with National Eye Institute Visual Function Questionnaire (NEI VFQ-25), FDT, and standard automated perimetry (SAP). Glaucoma patients had a median of 3 NEI VFQ-25, 8 FDT, and 8 SAP tests during follow-up. Mean sensitivities of the integrated binocular visual fields were estimated for FDT and SAP and used to calculate rates of change. A joint longitudinal multivariable mixed model was used to investigate the association between change in binocular mean sensitivities and change in NEI VFQ-25 Rasch-calibrated scores.ResultsThere was a statistically significant correlation between change in binocular mean sensitivity for FDT and change in NEI VFQ-25 scores during follow-up in the glaucoma group. In multivariable analysis with the confounding factors, each 1 dB/year change in binocular FDT mean sensitivity corresponded to a change of 0.8 units per year in the NEI VFQ-25 scores (P = .001). For binocular SAP mean sensitivity, each 1 dB/year change was associated with 2.4 units per year change in NEI VFQ-25 scores (P < .001). The multivariable model containing baseline and rate of change information from SAP had stronger ability to predict change in NEI VFQ-25 scores compared to the equivalent model for FDT (R(2) of 50% and 30%, respectively; P = .001).ConclusionSAP performed significantly better than FDT in predicting change in NEI VFQ-25 scores in our population, suggesting that it may still be the preferable perimetric technique for predicting risk of disability from the disease

Probabilistic Assessment of Grid Security for Different Scenarios of Power System Development

PurposeTo evaluate the association between longitudinal changes in quality of life (QoL) and rates of progressive visual field loss in glaucoma.DesignProspective observational cohort study.ParticipantsWe 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.MethodsAll 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 measuresThe relationship between change in NEI VFQ-25 Rasch-calibrated scores and change in binocular SAP MS.ResultsThere 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.ConclusionsBaseline 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