Progressive Changes in the Neuroretinal Rim and Retinal Nerve Fiber Layer in Glaucoma: Impact of Baseline Values and Floor Effects.

PURPOSE: To determine whether more severe baseline damage impedes measurement of minimum rim width (MRW) and peripapillary retinal nerve fiber layer thickness (RNFLT) change in glaucoma patients because of a floor effect. DESIGN: Prospective, longitudinal cohort study in a hospital-based setting. PARTICIPANTS: The study included patients with open-angle glaucoma and healthy control subjects. Participants had at least 5 years of follow-up with OCT every 6 months. METHODS: Baseline global and sectorial MRW and RNFLT values were classified as within normal limits, borderline, or outside normal limits based on reference normative values. Regression analysis was used to determine the magnitude and significance of MRW and RNFLT change. Additionally, the follow-up period for each participant was divided into 2 equal halves (first and second periods) to determine whether there was attenuation of MRW and RNFLT change with follow-up time. MAIN OUTCOME MEASURES: Rates of global and sectoral MRW and RNFLT changes (slopes). RESULTS: A total of 97 patients with glaucoma (median age, 70.3 years) and 42 healthy subjects (median age, 64.8 years) were followed for a median of 6.9 years and 7.0 years, respectively. The median mean deviation of the visual field in glaucoma patients was -4.30 decibels (dB) (interquartile range, -7.81 to -2.06 dB; range, -20.68 to 1.37 dB). Statistically significant changes in global and sectoral MRW and RNFLT were detected across all baseline classifications; however, there was a tendency for less change with increasing baseline damage. In glaucoma patients, RNFLT slopes, but not MRW slopes, were significantly more positive (less change) in the second period compared with the first. There were also no differences in MRW or RNFLT slopes in the first and second periods in healthy subjects. CONCLUSIONS: Significant MRW and RNFLT changes were detected at all levels of baseline damage. However, an attenuation in the rate of RNFLT change compared with MRW indicates an earlier floor effect in RNFLT measurements globally and in equivalent sectors. Because the axonal component of these measurements should be equivalent, our results suggest important differences in tissue remodeling at the level of the optic nerve head and peripapillary retina. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Variability of scan quality and perfusion density in longitudinal optical coherence tomography angiography imaging.

BACKGROUND/AIMS: Optical coherence tomography angiography (OCT-A) images are subject to variability, but the extent to which learning impacts OCT-A measurements is unknown. We determined whether there is a learning effect in glaucoma patients and healthy controls imaged with OCT-A. METHODS: Ninety-one open-angle glaucoma patients and 54 healthy controls were imaged every 4 months over a period of approximately 1 year in this longitudinal cohort study. We analysed 15°×15° scans, centred on the fovea, in one eye of each participant. Two-dimensional projection images for the superficial, intermediate and deep vascular plexuses were exported and binarised after which perfusion density was calculated. Linear mixed-effects models were used to investigate the association between perfusion density and follow-up time. RESULTS: The mean (SD) age of glaucoma patients and healthy controls was 67.3 (8.1) years and 62.1 (9.0) years, respectively. There was a significant correlation between perfusion density and scan quality in both glaucoma patients (r=0.50 (95% CI 0.42 to 0.58); p<0.05) and healthy controls (r=0.41 (95% CI 0.29 to 0.52); p<0.05). An increase in perfusion density occurred over time and persisted, even after adjustment for scan quality (1.75% per year (95% CI 1.14 to 2.37), p<0.01). CONCLUSIONS: Perfusion density measurements are subject to increasing experience of either the operator or participant, or a combination of both. These findings have implications for the interpretation of longitudinal measurements with OCT-A.

Non-arteritic anterior ischemic and glaucomatous optic neuropathy: Implications for neuroretinal rim remodeling with disease severity.

PURPOSE: Post-acute non-arteritic ischemic optic neuropathy (NAION) and glaucomatous optic neuropathy (GON) can be difficult to differentiate clinically. Our objective was to identify optical coherence tomography (OCT) parameters to help differentiate these optic neuropathies. METHODS: We compared 12 eyes of 8 patients with NAION and 12 eyes of 12 patients with GON, matched for age and visual field mean deviation (MD). All patients underwent clinical assessment, automated perimetry (Humphrey Field Analyzer II; Carl Zeiss Meditec, Dublin, CA, USA), and OCT imaging (Spectralis OCT2; Heidelberg Engineering, Heidelberg, Germany) of the optic nerve head and macula. We derived the neuroretinal minimum rim width (MRW), peripapillary retinal nerve fibre layer (RNFL) thickness, central anterior lamina cribrosa depth, and macular retinal thickness. RESULTS: MRW was markedly thicker, both globally and in all sectors, in the NAION group compared to the GON group. There was no significant group difference in RFNL thickness, globally or in any sector, with the exception of the temporal sector that was thinner in the NAION group. The group difference in MRW increased with increasing visual field loss. Other differences observed included lamina cribrosa depth significantly greater in the GON group and significantly thinner central macular retinal layers in the NAION group. The ganglion cell layer was not significantly different between the groups. CONCLUSIONS: The neuroretinal rim is altered in a dissimilar manner in NAION and GON and MRW is a clinically useful index for differentiating these two neuropathies. The fact that the difference in MRW between the two groups increased with disease severity suggests distinct remodelling patterns in response to differing insults with NAION and GON.

Elucidating macular structure-function correlations in glaucoma.

Correlation between structural data from optical coherence tomography and functional data from the visual field may be suboptimal because of poor mapping of OCT measurement locations to VF stimuli. We tested the hypothesis that stronger structure-function correlations in the macula can be achieved with fundus-tracking perimetery, by precisely mapping OCT measurements to VF sensitivity at the same location. The conventional 64 superpixel (3° × 3°) OCT grid was mapped to VF sensitivities averaged in 40 corresponding VF units with standard automated perimetry (conventional mapped approach, CMA) in 38 glaucoma patients and 10 healthy subjects. Similarly, a 144 superpixel (2° × 2°) OCT grid was mapped to each of the 68 locations with fundus-tracking perimetry (localized mapped approach, LMA). For each approach, the correlation between sensitivity at each VF unit and OCT superpixel was computed. Vector maps showing the maximum correlation between each VF unit and OCT pixel was generated. CMA yielded significantly higher structure-function correlations compared to LMA. Only 20% of the vectors with CMA and < 5% with LMA were within corresponding mapped OCT superpixels, while most were directed towards loci with structural damage. Measurement variability and patterns of structural damage more likely impact correlations compared to precise mapping of VF stimuli.

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

Importance: Estimating the rate of glaucomatous visual field change provides practical assessment of disease progression and has implications for management decisions. Objective: To assess the rates of visual field change in patients receiving treatment for glaucoma compared with healthy individuals over an extensive follow-up period and to quantify the impact of important covariates for these rates. Design, Setting, and Participants: This prospective longitudinal cohort study was conducted in a hospital-based setting from January 1991 to February 2020. The study included 40 patients receiving treatment for open-angle glaucoma and 29 healthy participants. One eye of each participant was randomly selected as the study eye. Exposures: Patients with glaucoma and healthy participants received testing with standard automated perimetry every 6 months. Individual rates of mean sensitivity change were computed using ordinary least-squares regression analysis, and linear mixed-effects modeling was used to estimate the mean rates of mean sensitivity change in the 2 groups and the impact of baseline mean sensitivity, baseline age, and follow-up intraocular pressure for rate estimates. Main Outcomes and Measures: Rate of mean sensitivity change in patients with glaucoma and healthy participants. Results: A total of 40 patients with glaucoma (median age, 53.07 years [IQR, 48.34-57.97 years]; 21 men [52%]) and 29 healthy participants (median age, 48.80 years [IQR, 40.40-59.07 years], 17 women [59%]) were followed up for a median of 25.65 years (IQR, 22.49-27.02 years) and 19.56 years (IQR, 16.19-26.21 years), respectively. Most participants (65 individuals [94%]) self-identified as White, with the exception of 2 patients with glaucoma (1 self-identified as Black and 1 as South Asian) and 2 healthy participants (both self-identified as South Asian). The mean follow-up intraocular pressure of patients with glaucoma (median, 15.83 mm Hg [IQR, 13.05-17.33 mm Hg]) was similar to that of healthy participants (median, 14.94 mm Hg [IQR, 13.28-16.01 mm Hg]; P = .25). In an ordinary least-squares regression analysis, 31 patients (78%) with glaucoma had rates of mean sensitivity change within the range of healthy participants (ie, between -0.20 dB/y and 0.15 dB/y). Linear mixed-effects modeling revealed that the mean (SE) rate of mean sensitivity change in healthy participants was 0.003 (0.033) dB/y (95% CI, -0.062 to 0.068; P = .93). In comparison, patients with glaucoma had a mean (SE) rate of mean sensitivity change that was -0.032 (0.052) dB/y faster, but this difference was not statistically significant (95% CI, -0.134 to 0.070; P = .53). Among covariates, only baseline mean sensitivity was associated with the rate of mean sensitivity change (mean [SE], 0.021 [0.010] dB/y/dB; 95% CI, 0.002-0.041; P = .03). Conclusions and Relevance: The results of this cohort study suggest that over a median follow-up of more than 25 years, the rate of visual field change in patients receiving treatment for glaucoma was comparable to that of healthy individuals. These findings could guide practitioners in making management decisions.

Impact of Glaucoma Severity on Rates of Neuroretinal Rim, Retinal Nerve Fiber Layer, and Macular Ganglion Cell Layer Thickness Change.

PURPOSE: To determine the impact of glaucoma severity on rates of change of minimum rim width (MRW), peripapillary retinal nerve fiber layer (RNFL), and macular ganglion cell layer (GCL) thickness. DESIGN: Prospective, cohort study. METHODS: Glaucoma patients and healthy subjects had optical coherence tomography scans at 6-month intervals. Individual rates of change for MRW, RNFL, and GCL thickness were estimated with ordinary least-squares regression. Linear mixed-effect models were used to estimate the rate of change of each parameter and evaluate the impact of glaucoma severity (expressed by visual field mean deviation, MD) and age on these rates. RESULTS: A total of 132 glaucoma patients and 57 healthy subjects were followed for a median of 4.3 years and 3.7 years, respectively. Healthy subjects had a statistically significant deterioration in MRW (-1.66 µm/year), RNFL (-0.46 µm/year), and GCL thickness (-0.22 µm/year). While glaucoma patients had a faster rate of change in each parameter compared with healthy subjects, only GCL thickness showed a statistically significant group difference (mean difference: -0.17 µm/year; P = .03). Older baseline age was associated with faster GCL thickness change (-0.07 µm/year; P = .03), but not other parameters. Baseline MD had no impact on the subsequent rates of change in any of the parameters. CONCLUSIONS: The rates of MRW, RNFL, and GCL thickness change were not significantly influenced by glaucoma severity at baseline; however, GCL thickness was able to statistically contrast the rate of change between healthy subjects and glaucoma patients throughout the disease spectrum.

Comparing Five Criteria for Evaluating Glaucomatous Visual Fields.

PURPOSE: No consensus exists on the relative superiority among criteria for evaluating glaucomatous visual field (VF) damage. We compared the sensitivities and specificities of 5 criteria-Glaucoma Hemifield Test (GHT), Hoddap-Anderson-Parrish 2 (HAP2), Foster, United Kingdom Glaucoma Treatment Study (UKGTS), and Low-pressure Glaucoma Treatment Study (LoGTS)-across various levels of functional and structural glaucomatous damage. DESIGN: Retrospective cross-sectional study. METHODS: This single-center study included patients with suspect or known glaucoma with reliable VF (Humphrey 24-2 Swedish Interactive Thresholding Algorithm) and optical coherence tomography (OCT; Spectralis, Heidelberg Engineering) examinations within a 4-month period. One eye per patient was included. The level of functional and structural damage was defined by mean deviation (MD) and by an OCT score, respectively. We created the OCT score by counting the number of abnormal (MD percentile [P] <1%) global and sectoral averages of optic nerve head MRW, circumpapillary RNFL thickness, and macular GCL thickness. We inferred specificities and sensitivities from positive rates of the criteria in patients with low glaucomatous damage (MD at P ≥ 10% or OCT score = 0) and with higher damage (MD at P < 10% or OCT score > 0), respectively. RESULTS: We included 1230 patients. In patients with low glaucomatous damage, HAP2 and UKGTS had higher positive rates, suggesting lower specificities, whereas GHT, Foster, and LoGTS had lower positive rates, suggesting higher specificities. In patients with higher glaucomatous damage, HAP2 and UKGTS had higher positive rates, indicating higher sensitivities, whereas GHT, Foster, and LoGTS had lower positive rates, indicating lower sensitivities. CONCLUSIONS: No criteria had uniformly superior performance. Selection of criteria should consider the degree of damage anticipated and the desire for either higher sensitivity or specificity.

The rates of visual field progression in glaucoma and its clinical importance / Taxas de progressão do campo visual em glaucoma e sua importância clínica

ABSTRACT The rate of visual field progression is an essential factor in determining risk of visual disability or blindness in glaucoma patients. Knowledge of the rate of progression of a particular patient, in combination with an estimation of their longevity and other clinical factors, allows clinicians to optimize management by providing appropriately aggressive treatment. Despite decades of research on the treatment of glaucoma, the natural history of glaucomatous visual field progression in untreated and treated patients remains unclear. The purpose of this review is to provide a comprehensive summary of the literature surrounding the rate of visual field progression in glaucoma. Most of the available data pertains to primary open angle glaucoma, but we will also review progression rates in other subtypes of open angle glaucoma, such as pseudoexfoliative glaucoma and normal tension glaucoma, as well as in primary angle closure glaucoma. Specifically, we will cover methods to identify rates of progression, rates of progression in treated versus untreated patients, factors that may influence progression, and lastly, suggest some parameters that might help clinicians in determining acceptable rates of visual field deterioration in patients with glaucoma.

RESUMO A taxa de progressão do campo visual é um fator essencial para determinar o risco de incapacidade visual ou cegueira em pacientes com glaucoma. Conhecer a taxa de progressão de um determinado paciente, em combinação com uma estimativa de sua longevidade e outros fatores clínicos, permite que os médicos otimizem a conduta, fornecendo um tratamento adequadamente agressivo. Apesar de décadas de pesquisa sobre o tratamento do glaucoma, a história natural da progressão do campo visual glaucomatoso em pacientes não tratados e tratados permanece pouco clara. O objetivo desta revisão é fornecer um resumo abrangente da literatura sobre a taxa de progressão do campo visual do glaucoma. A maioria dos dados disponíveis diz respeito ao glaucoma de ângulo aberto primário, mas também revisaremos as taxas de progressão em outros subtipos de glaucoma de ângulo aberto, como o glaucoma pseudoexfoliativo e o glaucoma de tensão normal, bem como o glaucoma primário de ângulo fechado. Especificamente, iremos cobrir métodos para identificar taxas de progressão, taxas de progressão em pacientes tratados versus não tratados, fatores que podem influenciar a progressão e, finalmente, sugerir alguns parâmetros que podem ajudar os médicos a determinar taxas aceitáveis de deterioração do campo visual em pacientes com glaucoma

Scholarly Impact of Academic Ophthalmologists and Vision Scientists in Canada.

OBJECTIVE: To outline the current impact of Canadian ophthalmology and vision science research as measured by novel research metrics. DESIGN: Cross-sectional survey. PARTICIPANTS: All Canadian ophthalmologists (n = 687) and vision scientists (n = 119) with an online bibliometric profile and academic appointment at a major ophthalmology training centre were included. METHODS: Faculty lists of Canada's 15 major academic ophthalmology departments were obtained. Faculty names, appointments, sex, and educational background were recorded. Elsevier's Scopus database was used to calculate H-index, m-quotient, and total citations for each faculty member. Details around grant funding were obtained through the Canadian Institutes of Health Research (CIHR) Funding Decisions Database. RESULTS: Average H-indices were 7.42 ± 7.98 for ophthalmologists and 23.78 ± 15.25 for vision scientists. Higher academic appointment was correlated with higher h-indices and m-quotients (p <0.0001 for both). Most academic departments had significantly more males than females (avg. 71% male, 29% female); however, more equal ratios were seen in faculties in Quebec. No significant differences in research impact were identified between male and female ophthalmologists when controlled for academic appointment and career stage (p > 0.05). In clinical ophthalmology research, the top three departments with the highest average H-indices were Western University, the University of Toronto, and Dalhousie University. The University of British Columbia, Université de Montréal, and McGill University received the most funding from the CIHR in the last 10 years. CONCLUSION: This study highlights the current scope of ophthalmology and vision science research in Canada. Important trends were identified in research productivity across academic rank, sex, and clinical subspecialty.

Efficacy and Safety of the Susanna Glaucoma Drainage Device After 1 Year of Follow-up.

PRECIS: This study found a rate of failure of 13.6% of the new Susanna Glaucoma Drainage Device (SGDD) after 1 year of follow-up. Severe complications occurred in 1 patient (4.5%). PURPOSE: The purpose of this study was to determine the success and complications rates of the SGDD implant in refractory glaucoma. PATIENTS AND METHODS: This is a retrospective study. Medical records from all consecutive refractory glaucoma patients (failed trabeculectomies with the use of adjunctive mitomycin) followed in a private clinical practice were included in the study. All patients had undergone SGDD implant surgery from September 2016 to July 2019 were included. All surgeries were done by the same surgeon (R.S.). Primary outcome was surgical failure, defined as intraocular pressure (IOP) >18 mm Hg and/or <20% IOP reduction from baseline, IOP<5 mm Hg, reoperation for glaucoma, need of implant removal or loss of light perception vision. Secondary outcomes included mean IOP, use of supplemental medical therapy, and complications. RESULTS: In all, 22 eyes were analyzed. Mean patient age was 63±15 years (range: 27 to 87 y). Mean IOP decreased from 23±7 to 11±8 mm Hg (P<0.001, paired t test) at an average of 18±9 months after the tube implant. The mean SD number of glaucoma medications was reduced from 3.3±1 to 1.5±1.2 at the last postoperative visit (P<0.01, paired t test). No early postoperative complications occurred. There was 1 case of late persistent hypotony in a patient with previous endocyclophotocoagulation that was solved with tube ligature with silk 8-0. Failure because of high IOP occurred in 2 cases. There was no extrusion or erosion of the tube and the plate. CONCLUSION: The SGDD presented a 13.6% failure rate (86.4% success rate) with very few complications, being an efficient and safe alternative for refractory glaucoma.

Value of 10-2 Visual Field Testing in Glaucoma Patients with Early 24-2 Visual Field Loss.

PURPOSE: To determine whether the 10-2 test of the Humphrey Field Analyzer detected a higher proportion of abnormal visual fields compared with the 24-2 test in the central 10° of patients with early glaucomatous visual field damage. DESIGN: Prospective observational study. PARTICIPANTS: Patients with open-angle glaucoma and healthy control participants. METHODS: All participants underwent a 24-2 and 10-2 test. Only the 12 central test locations of the 24-2 test were included to analyze equivalent visual field areas. The performance of the 2 tests was compared across 4 pointwise criteria: total deviation (TD) and pattern deviation (PD) analyses at the 5% and 2% levels. Analyses also were conducted for 2 pairs of follow-up tests, each performed 4 months apart. MAIN OUTCOME MEASURES: (1) Area under the receiver operating characteristic curve (AUC), (2) sensitivity at identically matched specificity for the 4 criteria, (3) overlap (entire field and by quadrant) of abnormal visual fields with both tests, and (4) repeatability of the findings in 2 subsequent follow-up tests. RESULTS: One eye each of 97 glaucoma patients (median mean deviation, -2.31 dB) and 65 control participants were included in the study. The AUCs for the 24-2 and 10-2 tests were not significantly different for any of the 4 criteria and ranged from 0.88 to 0.93 and from 0.91 to 0.94, respectively. At matched specificity, the sensitivity of the 24-2 test was significantly higher for all criteria except for PD analysis at 5%. In patients with an abnormal field with either test, the overlap varied from 60% to 86% depending on the criterion, whereas by quadrant, concordance ranged from 70% to 87%. Over the follow-up, the repeatability of test results (both 24-2 and 10-2 abnormal, either abnormal, or both normal) was achieved in 55% to 70% of patients. CONCLUSIONS: In this study of glaucoma patients with early damage with the 24-2 test, there was little evidence that adding the 10-2 test revealed additional undetected defects in the central visual field. It may be more prudent to reserve 10-2 testing for following up selected patients with higher risk of central visual field progression.

Discrepancy in Loss of Macular Perfusion Density and Ganglion Cell Layer Thickness in Early Glaucoma.

PURPOSE: To identify characteristics of patients with early open-angle glaucoma exhibiting greater macular perfusion density (PD) loss compared with macular ganglion cell layer (GCL) thickness loss. DESIGN: Cross-sectional study. METHODS: Optical coherence tomography (OCT) imaging of the optic nerve head and macula was conducted in patients and healthy control subjects. Minimum rim width, retinal nerve fiber layer and GCL thickness, and PD from OCT angiography were derived. Only high-quality images were included. For direct comparison, raw PD and GCL thickness values in patients were converted to relative age-corrected loss values based on data from controls. Demographic and ocular variables related to greater PD loss compared with GCL thickness loss were identified with multivariate logistic regression. RESULTS: Data from 89 patients (median mean deviation with the 24-2 and 10-2 tests, Humphrey Field Analyzer: -1.96 dB and -1.49 dB, respectively) and 54 controls were analyzed. Sixty-three (71%) patients had relatively more GCL thickness loss, whereas 26 (29%) had relatively more PD loss. More PD loss was associated with lower OCT and OCT-angiography signal strength (odds ratio [95% confidence interval], 0.64 [0.40, 0.96] and 0.60 [0.38, 0.86], per dB, respectively), thicker retinal nerve fiber layer thickness (1.08 [1.01, 1.16] per µm), and female sex (6.57 [1.25, 48.79]). CONCLUSION: Less than one-third of patients with early glaucoma had more loss of perfusion compared with conventional structural loss in the macula. Even within a range of high-quality images, lower signal strength may be at least partially responsible for apparent perfusion loss.

Asymmetry analysis of macular optical coherence tomography angiography in patients with glaucoma and healthy subjects.

BACKGROUND/AIMS: Quantitative analysis of optical coherence tomography angiography (OCT-A) images requires a reproducible approach that accounts for sectoral loss. The objective of this study was to determine whether an index that accounts for both global (perfusion density, PD) and asymmetric loss of perfusion, rather than PD alone, more reliably measures loss of perfusion in patients with glaucoma. METHODS: We analysed macular OCT-A scans of 95 glaucoma patients and 59 control subjects. Two-dimensional projection images corresponding to the superficial vascular plexus were exported and analyses performed to calculate global PD and image asymmetry. An unsigned perfusion asymmetry index (PAI) that included PD and asymmetry (with 1:1 wt) was calculated. Perfusion density and PAI were compared with 10-2 visual field mean deviation and ganglion cell layer (GCL) thickness. RESULTS: Median (IQR) visual field mean deviation was -1.73 (-3.76, 0.30) dB for the glaucoma group and 0.67 (0.16, 1.18) dB for the control group. The strength of the correlation with mean deviation was stronger for PAI (r=0.47), compared with PD (r=0.35), whereas with GCL thickness they were comparable (r=0.45 and 0.43, respectively). Compared with controls, mean PD was 12% lower in patients with glaucoma (0.27 vs 0.30), while PAI was 17% lower (0.40 vs 0.48). However, diagnostic accuracy of either PD or PAI was worse than GCL thickness. CONCLUSIONS: While PAI yielded better correlation with mean deviation and GCL thickness, and a slightly improved separation between patients with glaucoma and healthy controls, diagnostic accuracy was inferior compared with GCL thickness.

Influence of Bruch's Membrane Opening Area in Diagnosing Glaucoma With Neuroretinal Parameters From Optical Coherence Tomography.

PURPOSE: To determine whether the glaucoma diagnostic accuracy of age- and Bruch membrane opening area (BMOA)-adjusted normative classifications of minimum rim width (MRW) and retinal nerve fiber layer thickness (RNFLT) is dependent on BMOA, in a European descent population. DESIGN: Retrospective, cross-sectional study. METHODS: We included 182 glaucoma patients and 166 healthy controls for the primary study, and 105 glaucoma patients in a second sample used for a replication study. Optical coherence tomography (Spectralis) measurements of BMOA, global MRW, and RNFLT and normative classifications from the device software were exported for analysis. Sensitivity and specificity were calculated for a conservative criterion (abnormal = "outside normal limits" classification) and a liberal criterion (abnormal = "outside normal limits" or "borderline" classifications). The dependence of sensitivity and specificity on BMOA was analyzed with comparison among subgroups divided by tertiles of BMOA, and with logistic regression. RESULTS: For the conservative criterion, MRW sensitivity was independent of BMOA (P ≥ .76), while RNFLT sensitivity increased in the large BMOA subgroup (P = .04, odds ratio: 1.2 per mm2 [P = .02]). For the liberal criterion, MRW and RNFLT sensitivities were independent of BMOA (P ≥ .53). Specificities were independent of BMOA (P ≥ .07). For the replication sample, which included younger patients with larger BMOA and worse visual field damage than the primary sample, sensitivities were independent of BMOA for both criteria (P ≥ .10). CONCLUSIONS: RNFLT sensitivity was higher in eyes with larger BMOA; however, age and visual field damage may influence that association. MRW diagnostic accuracy was not dependent on BMOA.

Clinical relevance of protruded retinal layers in minimum rim width measurement of the optic nerve head.

BACKGROUND/AIMS: Optical coherence tomography (OCT) imaging of the optic nerve head minimum rim width (MRW) has recently been shown to sometimes contain components besides extended retinal nerve fibre layer (RNFL). This study was conducted to determine whether excluding these components, termed protruded retinal layers (PRLs), from MRW increases diagnostic accuracy for detecting glaucoma. METHODS: In this cross-sectional study, we included 123 patients with glaucoma and 123 normal age-similar controls with OCT imaging of the optic nerve head (24 radial scans) and RNFL (circle scan). When present, PRLs were manually segmented, and adjusted MRW measurements were computed. We compared diagnostic accuracy of adjusted versus unadjusted MRW measurement. We also determined whether adjusted MRW correlates better with RNFL thickness compared with unadjusted MRW. RESULTS: The median (IQR) visual field mean deviation of patients and controls was -4.4 (-10.3 to -2.1) dB and 0.0 (-0.6 to 0.8) dB, respectively. In the 5904 individual B-scans, PRLs were identified less frequently in patients (448, 7.6%) compared with controls (728, 12.3%; p<0.01) and were present most frequently in the temporal sector of both groups. Areas under the receiver operating characteristic curves and sensitivity values at 95% specificity indicated that PRL adjustment did not improve diagnostic accuracy of MRW, globally or temporally. Furthermore, adjusting MRW for PRL did not improve its correlation with RNFL thickness in either group. CONCLUSION: While layers besides the RNFL are sometimes included in OCT measurements of MRW, subtracting these layers does not impact clinical utility.

Outer retinal layer thickness in patients with glaucoma with horizontal hemifield visual field defects.

BACKGROUND/AIMS: To determine the effect of glaucoma on outer retinal layer thickness in eyes with horizontal hemifield visual field (VF) defects. METHODS: We conducted a cross-sectional study in glaucomatous eyes with repeatable (in three or examinations) horizontal hemifield VF (programme 24-2) defect defined as: all five nasal VF locations immediately either above or below the horizontal midline abnormal in the pattern deviation plot with p<0.5%; no mirror-image adjacent 5 VF locations abnormal in the pattern deviation plot and no non-edge VF locations in the non-affected hemifield abnormal in the pattern deviation plot with p<1%. We used optical coherence tomography to measure thickness of each retinal layer in the temporal macula (12° horizontally and 24° vertically) and computed the absolute (µm) and relative (%) intraindividual asymmetry between the perimetrically normal and abnormal hemimacula. RESULTS: We included 10 eyes of 8 patients with median age of 67 years and median VF mean deviation of -8.85 dB. The nerve fibre, ganglion cell and inner plexiform layers were significantly thinner in the perimetrically abnormal hemimacula (median asymmetry of -6.4, -11.5 and -3.8 µm, (corresponding to -27.7, -40.5 and -15.7 %), respectively, all p≤0.01). The inner nuclear layer was slightly thicker in the perimetrically abnormal hemimacula (median asymmetry of 1.3 µm (5.0 %), p=0.01). The outer plexiform, outer nuclear and photoreceptor layers asymmetry values were negligible. CONCLUSION: Our study showed no evidence that glaucoma has an effect on the outer retinal layer thickness. In contrast, a large impact was observed in inner layer thickness.

Visibility of Optic Nerve Head Structures With Spectral-domain and Swept-source Optical Coherence Tomography.

PURPOSE: To compare the visibility of deep optic nerve head (ONH) structures and the visible area of the anterior surface of the lamina cribrosa (ASLC) with spectral-domain optical coherence tomography (SD-OCT) and swept-source OCT (SS-OCT). MATERIALS AND METHODS: In total, 33 glaucoma patients were imaged with SD-OCT (Spectralis, 24 radial B-scans centered on the ONH) and SS-OCT (Atlantis, 12 radial and a horizontal and vertical raster scan pattern containing 5 lines each, centered on the ONH). One of the SS-OCT horizontal and vertical scans that was best matching with the horizontal and vertical scan lines with those of SD-OCT was selected. All B-scans were then exported and deidentified. An independent observer determined whether the posterior choroid, border tissue, anterior scleral canal opening, and LC insertion into the sclera were detectable in the matched scan lines. Bruch membrane opening (BMO) and ASLC were segmented manually in radial scans. The segmented points were combined into a single plane and a linear interpolation was used to define BMO and ASLC areas. RESULTS: The posterior choroid, border tissue, and anterior scleral canal opening were detectable in most patients (94% to 100%, 88% to 100%, and 76% to 100%, respectively) and were not different between SD-OCT and SS-OCT. The LC insertion detection rate was nonstatistically higher for SS-OCT compared with SD-OCT (58% to 85% vs. 42% to 73%; P>0.10). The mean (SD) ASLC visible area (percentage of the respective BMO area) was 124 (30%) with SD-OCT and 135 (32%) with SS-OCT (P<0.01). CONCLUSION: SD-OCT and SS-OCT had comparable detection rates of deep ONH structures; however, a larger area of ASLC was visible with SS-OCT.