Joseph L. Simonson

Factors Associated With Focal Lamina Cribrosa Defects in Glaucoma

PURPOSE To assess factors associated with focal lamina cribrosa (LC) defects in glaucoma. METHODS Serial enhanced depth imaging (EDI) optical coherence tomography (OCT) B-scans of the optic nerve head were obtained from glaucoma patients. EDI OCT scans were reviewed for focal LC defects (laminar holes or disinsertions). Evaluated clinical factors included age, central corneal thickness, visual field (VF) mean deviation (MD), exfoliation syndrome, normal-tension glaucoma (NTG), disc hemorrhage, and intraocular pressure (IOP) during past follow-up. RESULTS One hundred forty-eight glaucomatous eyes (148 patients; mean age, 68 ± 12 years; mean VF MD, -11.63 ± 6.96 dB) were included. Sixty-seven (45%) eyes had focal LC defects and 81 (55%) did not. Eyes with focal LC defects had a higher prevalence of both disc hemorrhage (25% vs. 6%) and NTG (33% vs. 9%) and worse VF MD (-14.12 vs. -9.58 dB) than those without focal LC defects (P = 0.002, P < 0.001, and P < 0.001, respectively). In the multivariate logistic regression analysis, higher frequency of disc hemorrhage detection (odds ratio [OR], 3.63; P = 0.032), a diagnosis of NTG (OR, 4.23; P = 0.005), and worse VF MD (OR, 1.11; P < 0.001) were significant factors associated with the presence of focal LC defects. Disc hemorrhage developed in the same half of the disc as the largest or the second largest focal LC defect in 15 of 17 eyes (88.2%). CONCLUSIONS Disc hemorrhage, a diagnosis of NTG, and more advanced glaucoma status are associated with focal LC defects. Future studies are needed to elucidate the cause-and-effect relationships between focal LC defects and these factors.

Parafoveal scotoma progression in glaucoma: humphrey 10-2 versus 24-2 visual field analysis.

OBJECTIVE To compare the performance of 10-2 versus 24-2 visual fields (VFs) in detecting progression of initial parafoveal scotoma (IPFS) in glaucomatous eyes. DESIGN Retrospective, observational study. PARTICIPANTS Glaucoma patients with the following criteria: (1) an IPFS (≥ 3 adjacent points with P<0.05 within the central 10° degrees of fixation, 1 point or more with P<0.01 lying at the innermost paracentral points, and no scotoma outside the central 10°) in either hemifield based on 2 reliable Humphrey 24-2 Swedish interactive threshold algorithm standard VFs, and (2) 5 or more 10-2 and 24-2 VFs. METHODS Based on threshold map sensitivities, VF progression, defined as having 1 or more significantly progressing point(s) with a slope of sensitivity of less than -1.0 dB/year at P<0.01, was evaluated using pointwise linear regression. MAIN OUTCOME MEASURES The number of progressing eyes in 10-2 and 24-2 VF analyses. RESULTS Fifty eyes (50 patients) were included (mean age ± standard deviation, 62 ± 9 years). Mean follow-up period (5.7 vs. 5.6 years) and number of VFs (7.6 vs. 7.8) were similar between 10-2 and 24-2 analyses (all P>0.3). Significantly more progressing eyes were detected in 10-2 than in 24-2 analyses (24 vs. 11 eyes; P = 0.007). This difference became greater within the central 10° (24 vs. 4 eyes; P<0.001). Four of the 11 progressing eyes in 24-2 analysis were missed in 10-2 analysis, whereas 17 of the 24 progressing eyes in 10-2 analysis were missed in 24-2 analysis. The 4 progressing eyes missed in 10-2 analysis had progressing point(s) only outside the central 10° in 24-2 analysis. The other 3 eyes with progressing point(s) only outside the central 10° in 24-2 analysis were detected as progressing in 10-2 analysis. Similar results were obtained when more stringent criteria (at least 2 significantly progressing points within the same hemifield) were used for VF progression. CONCLUSIONS The 10-2 VF detects more progressing eyes than the 24-2 VF in glaucoma patients with IPFS, suggesting that closer surveillance of the central VF using testing algorithms with closely spaced grids is warranted in eyes with parafoveal scotomas. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.

Progression Pattern of Initial Parafoveal Scotomas in Glaucoma

OBJECTIVE To characterize the progression pattern of initial parafoveal scotomas (IPFSs) using cross-sectional and longitudinal 10-2 visual field (VF) data. DESIGN Retrospective, observational study. PARTICIPANTS Glaucoma patients with an IPFS in either hemifield based on 2 reliable 24-2 Swedish interactive threshold algorithm standard VFs (≥3 adjacent points with P<0.05 within the central 10° of fixation, 1 point or more with P<0.01 lying at the innermost paracentral points, and no scotoma outside the central 10°) and at least 2 10-2 VFs (first and last VFs 1 year or more apart). METHODS To simulate a cohort with an extended follow-up, eyes with an IPFS were divided into subgroups based on the severity of glaucoma using their 10-2 VF pattern standard deviation (PSD). Cross-sectional data were used to create an average pattern deviation map that was generated by averaging pattern deviation map values of 10-2 VF point-by-point within each subgroup. Longitudinal data (eyes with 5 or more 10-2 VFs) was used to perform pointwise linear regression analysis of pattern deviation values. Patterns of IPFS progression were identified from these cross-sectional and longitudinal assessments. MAIN OUTCOME MEASURES Average pattern deviation maps (cross-sectional) and maps of progression rates (longitudinal) in different disease severity subgroups. RESULTS Eighty eyes (80 patients) and 40 eyes (40 patients) with an IPFS were included for cross-sectional and longitudinal analyses, respectively. The mean age ± standard deviation, 24-2 VF mean deviation, and 24-2 VF PSD for all eyes were 63±10 years, -3.27±2.18 dB, and 5.46±2.40 dB, respectively. Based on maps generated in both cross-sectional and longitudinal analyses, IPFS in the superior hemifield had an arcuate pattern initially that later deepened approximately 3° to 5° above fixation. The scotoma then elongated toward the physiologic blind spot and spread toward the nasal periphery, sparing the area corresponding to the papillomacular bundle. The IPFS in the inferior hemifield had a similar pattern, but was slightly farther from fixation. CONCLUSIONS Superior and inferior IPFS have a similar characteristic pattern of progression, although the latter tend to be farther from fixation. Understanding these patterns should help in the management of such patients and in improving VF testing algorithms.

Defining 10-2 Visual Field Progression Criteria: Exploratory and Confirmatory Factor Analysis Using Pointwise Linear Regression

PURPOSE To test different visual field progression criteria using trend analysis in a glaucoma population followed with long sequences of 10-2 tests as a first attempt to understand and document rates of progression in the central field. DESIGN Retrospective cohort study. PARTICIPANTS We included 146 eyes of 146 patients with established glaucoma. METHODS Pointwise linear regression analysis using the methods of ordinary least squares was performed on the 68 test locations of the 10-2 visual field sequences. Threshold sensitivities at each test location were plotted as the dependent variable against follow-up time as the independent variable. Statistically significant progression or improvement of a visual field test point was defined if its regression slope measured ≤-1.0 dB/year or ≥+1.0 dB/year, respectively, at P<0.01. We explored sets of criteria to define visual field progression, generating a hypothetical sensitivity (progression), specificity (improvement), and progression-to-improvement ratio (PIR) for each criterion. The criterion with the highest PIR was deemed the one with best performance. Latent class analysis (LCA) was used to determine visual field sectors with highest inter-correlation. MAIN OUTCOME MEASURES The performance of different visual field progression criteria to detect fast rates of mean deviation (MD) change. RESULTS Median baseline 10-2 MD value was -12.0 dB (interquartile range [IQR], -6.7 to -17.8 dB), and the median rate of 10-2 MD change over time was -0.38 dB/year (IQR, -0.07 to -0.77 dB/year). The highest PIR was obtained with the progression criterion requiring at least 3 test points located in the same LCA-derived 10-2 visual field sector progressing faster than -1.0 dB/year at P<0.01. This criterion was further validated for content and convergence. CONCLUSIONS This is the first study to investigate progression criteria for 10-2 visual fields using rates of change and to test their performance and validity. These findings may be useful to improve the monitoring of patients with glaucoma at different levels of functional loss and to develop new perimetric algorithms that scrutinize specific visual field locations for a more accurate detection of progression.

Assessment of patient perception of glaucomatous visual field loss and its association with disease severity using Amsler grid

Purpose To investigate patients’ perception of glaucomatous VF loss and its association with glaucoma severity using the Amsler grid test. Methods In this prospective cross-sectional study, glaucoma patients with abnormal 10–2 Humphrey Swedish Interactive Threshold Algorithm-standard VF tests were enrolled consecutively. All patients underwent a black-on-white Amsler grid test for each eligible eye. They were asked to outline any perceived scotomas (areas with abnormal grid lines) on the grid and then describe verbally their perception of the scotomas. Examiners asked patients to clarify their descriptions. All descriptions used by patients were recorded in their own words, which were then sorted into descriptor categories according to similar themes. The number of descriptor categories was counted for each eye. 10–2 VF mean deviation (MD) was compared among eyes that reported different number of descriptor categories. The mean 10–2 VF MD values were compared among different descriptor categories. Results Fifty glaucoma patients (88 eyes) were included. Patients used a total of 44 different descriptors for their scotomas. Patients’ descriptors were classified into categories that incorporated similar themes, resulting in 4 overarching descriptor categories: Missing/White, Blurry/Gray, Black, and Not Aware. Fifty-two eyes reported one descriptor category and 19 eyes reported two descriptor categories (mean number of descriptor categories = 1.27±0.45). Eyes that reported two descriptor categories had worse VF MD than those that reported one (-17.86±10.31 dB vs. -12.08±7.53 dB; p = 0.012). When eyes were organized according to its combination of descriptor categories, each eye naturally sorted into one of the following 5 groups, in frequency order: Missing/White (27 eyes; 31%), Blurry/Gray (21 eyes; 24%), combined Missing/White and Blurry/Gray (19 eyes; 21%), Not Aware (17 eyes; 19%), and Black (4 eyes; 5%). The mean 10–2 VF MD severity order was Black (-21.18±10.59 dB), combined Missing/White and Blurry/Gray (-17.86±10.31 dB), Missing/White (-11.92±6.76 dB), Blurry/Gray (-10.55±7.03 dB), and Not Aware (-3.91±4.05 dB) (p<0.001). Conclusion Paracentral vision loss in glaucoma is perceived by patients. As the perception of scotomas and the variety of terms to describe scotomas are related to glaucoma severity, clinicians should pay attention to patients’ subjective descriptions of their glaucomatous VF loss. The historical notion that glaucoma patients lose their peripheral vision first and eventually look through a black tunnel needs to be updated to reflect the true perception of glaucoma.