Comparison of Rates of Progression of Macular OCT Measures in Glaucoma.

Purpose: The purpose of this study was to compare rates of change of various macular thickness measures and evaluate the influence of baseline damage on macular rates of change. Methods: One hundred twelve eyes (112 patients) with ≥ 2 years of follow-up and ≥ 5 macular optical coherence tomography (OCT) images and 10-2 visual field (VF) tests were included. OCT measures of interests were full macular thickness (FMT), ganglion cell complex (GCC), ganglion cell/inner plexiform layer (GCIPL), ganglion cell layer (GCL), and outer retinal layer (ORL) thickness in 3° × 3° superpixels. Rates of change were estimated with linear regression and normalized by dividing rates by the average normative superpixel thickness. We compared rates of change and proportion of significantly worsening superpixels (detection rate) and improving superpixels (false discovery rate [FDR]) among macular measures as a function of baseline thickness and 10-2 VF status. Results: Median (interquartile range [IQR]) baseline VF mean deviation, follow-up time, and number of VFs/OCTs were -7.6 dB (-11.8 to -3.8 dB), 4.5 years (4.0-5.0 years), and 9 (8-10), respectively. Normalized FMT and GCC rates of change were faster and detection rates were higher than GCIPL and GCL (P < 0.001), but FMT had lower FDR than GCC (P = 0.02); faster FMT rates were partially explained by ORL rates of change. GCC detection rates were less likely than GCIPL and GCL rates to decrease with diminishing baseline thickness or worse VF damage. In eyes with 10-2 VF worsening, GCC and GCL demonstrated the fastest rates of change. Conclusions: GCC measurements are most likely to detect structural worsening along the spectrum of glaucoma severity. Although FMT rates of change are least influenced by baseline thickness, they partially reflect likely age-related ORL changes. Translational Relevance: GCC thickness measurements seem to be the optimal macular outcome measure for detection of glaucoma deterioration.

Macular imaging with optical coherence tomography in glaucoma.

With the advent of spectral-domain optical coherence tomography, imaging of the posterior segment of the eye can be carried out rapidly at multiple anatomical locations, including the optic nerve head, circumpapillary retinal nerve fiber layer, and macula. There is now ample evidence to support the role of spectral-domain optical coherence tomography imaging of the macula for detection of early glaucoma. Macular spectral-domain optical coherence tomography measurements demonstrate high reproducibility, and evidence on its utility for detection of glaucoma progression is accumulating. We present a comprehensive review of macular spectral-domain optical coherence tomography imaging emerging as an essential diagnostic tool in glaucoma.

Relationship of the Macular Ganglion Cell and Inner Plexiform Layers in Healthy and Glaucoma Eyes.

PURPOSE: To explore factors influencing the inner plexiform layer (IPL) in healthy subjects and to test the hypothesis that IPL thickness is preferentially decreased in glaucoma as compared with ganglion cell layer (GCL) thickness. METHODS: Ninety-nine glaucomatous eyes and 66 healthy eyes (165 subjects) underwent macular spectral-domain optical coherence tomography (SD-OCT) imaging and GCL and IPL were segmented creating 8 × 8 arrays of 3° × 3° superpixels. The central 24 superpixels were categorized into three levels of eccentricity (∼1.5°, 4.5°, and 7.5° from the foveal center). Linear mixed models were used to determine predictive parameters for IPL thickness in healthy subjects and to explore the influence of diagnosis of glaucoma on IPL thickness taking into account the effect of GCL thickness and other covariates. RESULTS: Being located at 4.5° eccentricity predicted thicker IPL compared with 1.5° eccentricity (P < 0.001) in multivariable models in healthy subjects, whereas older age (P = 0.001) and Asian ethnicity (P = 0.021) were associated with thinner IPL. Diagnosis of glaucoma was not associated with thinner IPL regardless of eccentricity after accounting for age and ethnicity. The results were similar when only eyes with mean deviation greater than -6 dB were analyzed. CONCLUSIONS: Ethnicity and distance from the fovea are the main determinants of IPL thickness in the central macula. Preferential thinning of the macular IPL, compared with GCL, could not be detected in this study regardless of glaucoma stage. TRANSLATIONAL RELEVANCE: There is no evidence for preferential thinning of the macular IPL in glaucoma compared with GCL based on currently available SD-OCT-imaging technology.

Longitudinal Macular Structure-Function Relationships in Glaucoma and Their Sources of Variability.

PURPOSE: To review central structure-function (SF) relationships in glaucoma; to compare contributions of within-session and between-session variability to total variability of macular optical coherence tomography (OCT) thickness measurements; and to test the hypothesis that longitudinal within-eye variability of central SF relationships is smaller than between-individual variability. METHODS: We reviewed the pertinent literature on central SF relationships in glaucoma. Thirty-eight eyes (20 normal or glaucoma subjects) had ×3 macular images per session over 3 sessions, and superpixels thickness measurements for ganglion cell layer (GCL), ganglion cell/inner plexiform layer (GCIPL), ganglion cell complex (GCC), and full macular thickness (FMT) were exported. Linear mixed models were used for estimating contributions of between- and within-session variability to total thickness variability. One hundred twenty eyes with ≥3 10° visual fields (VFs)/OCT images were enrolled for the longitudinal study. We investigated within-eye longitudinal SF relationships (GCIPL thickness vs VF total deviations) with a change-point regression model and compared within-eye to between-individual variabilities with components-of-variance models. RESULTS: In the cross-sectional study, the between-session component contributed 8%, 11%, 11%, and 36% of total variability for GCL, GCIPL, GCC, and FMT, respectively. In the longitudinal study, between-individual variability explained 78%, 77%, and 67% of total SF variability at 3.4°, 5.6°, and 6.8° eccentricities, respectively (P < .05). SF relationships remained stable over time within individual eyes. CONCLUSIONS: Within-session variability accounts for most of macular thickness variability over time. Longitudinal within-eye SF variability is smaller than between-individual variability. Study of within-eye SF relationships could help clinicians better understand SF linking in glaucoma and help refine progression algorithms. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Cataract Surgery and Rate of Visual Field Progression in Primary Open-Angle Glaucoma.

PURPOSE: To test the hypothesis that cataract surgery slows the apparent rate of visual field (VF) decay in primary open-angle glaucoma patients compared with rates measured during cataract progression. DESIGN: Retrospective cohort study. METHODS: Consecutive open-angle glaucoma patients who underwent cataract surgery and who had ≥4 VFs and ≥3 years of follow-up before and after surgery were retrospectively reviewed. Mean deviation (MD) rate, visual field index (VFI) rate, pointwise linear regression (PLR), pointwise rate of change (PRC), and the Glaucoma Rate Index (GRI) were compared before and after cataract surgery. RESULTS: A total of 134 eyes of 99 patients were included. Median (interquartile range) follow-up was 6.5 (4.7-8.1) and 5.3 (4.0-7.3) years before and after cataract surgery, respectively. All intraocular pressure (IOP) parameters (mean IOP, standard deviation of IOP, and peak IOP) significantly improved (P < .001) after cataract surgery. All VF indices indicated an accelerated VF decay rate after cataract surgery: MD rate (-0.18 ± 0.40 dB/year vs -0.40 ± 0.62 dB/year, P < .001), VFI rate (-0.44% ± 1.09%/year vs -1.19% ± 1.85%/year, P < .001), GRI (-5.5 ± 10.8 vs -13.5 ± 21.5; P < .001), and PRC (-0.62% ± 2.47%/year before and -1.35% ± 3.71%/year after surgery; P < .001) and PLR (-0.20 ± 0.82 dB/year before and -0.42 ± 1.16 dB/year after surgery; P < .001) for all VF locations. Worse baseline MD and postoperative peak IOP were significantly associated with the postoperative VF decay rate and the change in the decay rate after cataract surgery. CONCLUSION: Although all IOP parameters improved after cataract surgery, VFs continued to progress. Cataract surgery does not slow the apparent rate of glaucomatous VF decay as compared to rates measured during the progression of the cataract.

Outcomes of Glaucoma Drainage Device Surgery in Eyes with Treated Uveal Melanoma.

AIM: We report patient safety and intraocular pressure (IOP) control after placement of a glaucoma drainage device (GDD) in eyes with a history of treated malignant uveal melanoma. METHODS: A retrospective review of the records of patients with uveal melanoma was performed. Outcomes were local tumor recurrence, rate of metastases, and to-nometric success, based on survival curves, defined as IOP < 21 mm Hg. RESULTS: Eleven eyes with choroidal melanoma, 4 with iris melanoma, and 1 with ciliary body melanoma were followed for a median (interquartile range) of 2.1 (1.1-3.2) years. Two subjects developed liver metastases; one had monosomy 3 and tumor gene expression profile class 2. The other case with ciliary body melanoma was negative for monosomy 3. There were no cases of local treatment failure. Mean preoperative IOP decreased from 30.5 ± 7.7 to 15.9 ± 8.1 mm Hg at 1 year after surgery (1-year success rate 80%). CONCLUSIONS: Our case series with a median follow-up of 2 years shows that placing a GDD in patients with treated uveal melanoma does not expose patients to greater risk of local or extraocular recurrence. A larger series and longer follow-up time are required to fully evaluate the safety of GDDs in this clinical scenario.

Observational Outcomes of Initial Trabeculectomy With Mitomycin C in Patients of African Descent vs Patients of European Descent: Five-Year Results.

Importance: There is evidence that patients of African descent (AD) experience higher surgical failure rate after trabeculectomy without antimetabolites. Objective: To compare outcomes of initial trabeculectomy with mitomycin C in AD patients with those of patients of European descent (ED) and to identify prognostic factors for failure. Design, Setting, and Participants: In this retrospective matched cohort study, 135 eyes of 105 AD patients were matched with 135 eyes of 117 ED patients by age (within 5 years), surgeon, lens status, and follow-up time (within 1 year) from a single tertiary academic center. Interventions: Initial trabeculectomy with mitomycin C. Main Outcomes and Measures: Criteria A, B, and C defined qualified success rates as final intraocular pressure of 18 mm Hg or less, 15 mm Hg or less, and 12 mm Hg or less, respectively, in addition to 20% or more, 25% or more, and 30% or more reduction of intraocular pressure or reduction of 2 or more medications. Kaplan-Meier survival curves were compared with log-rank test in AD and ED patients, and Cox proportional hazard models were used to estimate the influence of race/ethnicity on surgical success accounting for confounding variables. Results: Of the 105 AD patients, 56 (53.3%) were female, and the mean (SD) age was 67.5 (10.4) years; of the 117 ED patients, 64 (54.7%) were female, and the mean (SD) age was 68.2 (10.0) years. For AD patients compared with ED patients, the qualified success rates at 5 years for criteria A were 61% and 67%, respectively (difference, 7.3%; 95% CI, 4.4-10.4); for criteria B, 43% and 60% (difference, 17.6%; 95% CI, 15.2-20.0); and for criteria C, 25% and 40% (difference, 15.8%; 95% CI, 11.1-20.5). On multivariable Cox regression analyses, AD was associated with higher failure rate with criteria B and C for qualified success and with all criteria for complete success (ie, no need for medications). Incidence of bleb leaks was higher in the AD group (29 vs 11 eyes; P = .002). Additionally, AD patients required additional glaucoma surgeries more often than ED patients (47 vs 26 eyes; P = .004). Conclusions and Relevance: African descent was associated with higher failure rates and higher incidence of bleb leaks after initial trabeculectomy with mitomycin C compared with European descent. If this is subsequently shown to be a cause and effect, the findings need to be considered when surgical treatment of glaucoma is contemplated in AD patients.

Long-term Outcome of Second Ahmed Valves in Adult Glaucoma.

PURPOSE: To evaluate the long-term outcomes of second Ahmed glaucoma valve (AGV) implants in eyes with glaucoma. DESIGN: Retrospective interventional case series. METHODS: Patients with sequential second Ahmed valves implanted in the same eye from 1994 to 2016 were included. Success was defined with 3 criteria: (1) intraocular pressure (IOP) ≤ 21 mm Hg and IOP reduction of 20%; (2) IOP ≤ 18 mm Hg and IOP reduction of 25%; and (3) IOP ≤15 mm Hg and IOP reduction of 30%. The primary analysis was the 5-year Kaplan-Meier survival rate for each criterion. Failure was established when the success criterion was not met at 2 consecutive visits at least 3 months after the surgery. Loss of light perception, requirement for additional glaucoma surgery, hypotony maculopathy, and serious complications were also considered failures. RESULTS: One hundred ten eyes from 104 patients were included with a mean follow-up of 5.0 years (interquartile range [IQR] 1.6-7.33 years). The median (IQR) age at the second AGV was 68.0 (53.5-77.9) years. The median (IQR) time between surgeries was 2.1 (0.7-4.0) years. The 5-year Kaplan-Meier survival rates were 57%, 51%, and 30% for criteria 1, 2, and 3, respectively. CONCLUSION: A second AGV is effective in reducing IOP in patients who require additional IOP lowering after a first AGV. The success rates are comparable to primary AGV implantation, and to trabeculectomy in eyes with a previously implanted glaucoma drainage device. A second AGV is a viable option in eyes with inadequate IOP levels after a primary AGV.

Association of Structural and Functional Measures With Contrast Sensitivity in Glaucoma.

PURPOSE: To test the hypothesis that structural and functional measures predict contrast sensitivity (CS) outcomes in glaucomatous eyes. DESIGN: Cross-sectional prospective study. METHODS: One hundred five eyes of 65 patients who underwent macular spectral-domain optical coherence tomography imaging, 24-2 standard achromatic visual fields (VF), and CS measurement on the same day were enrolled. Association of CS at 4 spatial frequencies (3, 6, 12, and 18 cycles per degree, cpd) with structural and functional outcomes was explored with correlation and regression analyses. RESULTS: The median (IQR) 24-2 visual field mean deviation was -7.6 (-11.1 to -3.0). Significant correlations were found between CS at 6 cpd and ganglion cell/inner plexiform layer thickness at inferotemporal and inferonasal macular sectors (ρ = 0.222, P = .023 and ρ = 0.209, P = .032, respectively). CS at 6 cpd demonstrated higher correlations with full macular thickness measurements, the strongest of which was with the central macular thickness in the superior 6 × 3-degree region (ρ = 0.311, P = .001). Contrast sensitivity at 6 cpd also had the strongest correlation with mean deviation of the 4 central VF points (ρ = -0.420; P < .001). There was a significant correlation between logMAR visual acuity and contrast sensitivity at 6, 12, and 18 cpd (ρ = -0.306, ρ = -0.348 and ρ = -0.241, P < .013, respectively). CONCLUSIONS: Structural and functional measures showed a fair relationship with contrast sensitivity. This association was most prominent between full-thickness macular measures or central VF parameters and CS at 6 cpd. Contrast sensitivity was not a reliable surrogate for glaucoma severity in this cross-sectional study.