Investigation of progression pattern and associated risk factors in glaucoma patients with initial paracentral scotomas using Humphrey 10-2

Assessment of silent reading ability among glaucoma patients using an eye tracking system with horizontally scrolling text

PURPOSE

There have been many reports suggesting that glaucoma patients with visual field defects may have decreased silent reading ability compared with individuals without glaucoma. This study used an eye tracking system to assess the ability of glaucoma patients to silently read horizontally scrolling text.

METHODS

Glaucoma patients who met the following criteria were recruited: age of ≤ 70 years, at least one eye with a 10 - 2 threshold on standard automated perimetry, a mean deviation value of n 4.0 dB or less, and corrected decimal visual acuity of 0.7 or better in both eyes. Using heat map images created from data from an eye tracking system operating during presentation of a video in which a sentence scrolled horizontally from right to left, reading time, average gaze position, and average fixation time (AFT) were compared between normal eyes (23 individuals, 46 eyes) and glaucomatous eyes (25 patients, 45 eyes). Four styles of sentences (large slow, large fast, small slow, and small fast) were scrolled in the top or bottom sections of the screen.

RESULTS

Primary open-angle glaucoma was the most common type of glaucoma in 34 eyes (75.6%), followed by secondary glaucoma in six eyes (13.3%). In comparison with normal eyes, the reading time among right eyes was significantly longer in glaucomatous eyes when reading large fast text that was shown in the bottom area and left glaucomatous eyes showed a leftward shift in gaze position in the top, bottom, or both sections with all four sentence types. There was no significant difference in AFT between glaucomatous and normal eyes across the four sentence styles. In the left eye with inferior visual field loss, text presented at the top consistently showed a correlation with leftward shift of the gaze position across all scenarios.

CONCLUSION

Glaucoma patients with central visual field defects in their left eyes may experience greater difficulty reading horizontally scrolling text than individuals with normal eyes.

Structural and vascular changes in glaucoma with single-hemifield defect: predictors of opposite hemifield visual field progression

PURPOSE

To investigate longitudinal changes in optic nerve head (ONH) superficial vessel density (VD), macular VD, circumpapillary retinal nerve fiber layer (RNFL) thickness, and macular ganglion cell-inner plexiform layer (GCIPL) thickness, and their associations with future VF defects in unaffected hemifields of primary open angle glaucoma (POAG) eyes with baseline VF defect confined to a single hemifield.

METHODS

This retrospective observational study included 61 POAG eyes with VF defect confined to a single hemifield monitored over a mean follow-up time of 2.7 years. Development of VF defect in opposite hemifield was defined based the Early Manifest Glaucoma Trail criteria. Each eye was classified into either "conversion" or "no conversion" groups according to development of VF defect in the unaffected hemifield. The rates of longitudinal changes in VD and structure parameters in each hemiretina were compared between the two groups. A Cox proportional hazard model was used to identify potential risk factors for VF conversion in the unaffected hemifield.

RESULTS

Among 61 eyes, 17 eyes (27.9%) were classified as "conversion" and 44 eyes (72.1%) were classified as "non-conversion" groups. The conversion group exhibited significantly greater rates of both VD and structural changes in both hemiretinas. In Cox proportional hazard model, greater rate of change in GCIPL thickness, ONH superficial VD, and macular VD of both hemiretinas and greater rate of change in RNFL thickness of the unaffected hemiretina were identified as risk factors for VF conversion in the unaffected hemifield.

CONCLUSIONS

Monitoring progressive changes in VD and structural parameters effectively predict future VF defect in the opposite hemifields of POAG eyes with single-hemifield defects.

The number of examinations required for the accurate prediction of the progression of the central 10-degree visual field test in glaucoma

The purpose of the study was to investigate the number of examinations required to precisely predict the future central 10-degree visual field (VF) test and to evaluate the effect of fitting non-linear models, including quadratic regression, exponential regression, logistic regression, and M-estimator robust regression model, for eyes with glaucoma. 180 eyes from 133 open angle glaucoma patients with a minimum of 13 Humphrey Field Analyzer 10-2 SITA standard VF tests were analyzed in this study. Using trend analysis with ordinary least squares linear regression (OLSLR), the first, second, and third future VFs were predicted in a point-wise (PW) manner using a varied number of prior VF sequences, and mean absolute errors (MAE) were calculated. The number of VFs needed to reach the minimum 95% confidence interval (CI) of the MAE of the OLSLR was investigated. We also examined the effect of applying other non-linear models. When predicting the first, second, and third future VFs using OLSLR, the minimum MAE was obtained using VF1-12 (2.15 ± 0.98 dB), VF1-11 (2.33 ± 1.10 dB), and VF1-10 (2.63 ± 1.36 dB), respectively. To reach the 95% CI of these MAEs, 10, 10, and 8 VFs were needed for the first, second and third future VF predictions, respectively. No improvement was observed by applying non-linear regression models. As a conclusion, approximately 8-10 VFs were needed to achieve an accurate prediction of PW VF sensitivity of the 10-degree central VF.

Cluster Formation for Analyses of Glaucomatous Visual Field Defects in Central 10-2 Visual Field in Normal Tension Glaucoma Eyes

Purpose

To develop a cluster system to analyze the retinal sensitivity loss of 68 test points in the central 10 degrees of standard automated perimetry (SAP) in eyes with normal tension glaucoma (NTG).

Patients and Methods

Patients with NTG who met the following criteria were included: visual acuity ≥0.7, SAP-derived mean deviation ≥−15 dB, and pattern deviation probability plots with at least one point with a probability of <0.5% and/or two or more contiguous points with a probability of <1% that did not cross the horizontal meridian in the central 12 points of the 24-2 test points. SAP with the Swedish Interactive Threshold Algorithm Standard (SITA-S) 10-2 program (10-2) was performed within 6 months of the SITA-S 24-2. The averaged total deviation (TD) for each of the 68 test points in the 10-2 was calculated. Hierarchical cluster analyses were performed based on the deviation of the TDs of the test points, and a dendrogram was created. The number of clusters was determined following the Sturges’ rule.

Results

One hundred and twenty-six eyes of 126 patients (61.9±11.4 years) were studied. Hierarchical cluster analysis of the TD values statistically obtained a dendrogram that divided the 68 test points into 7 clusters. Of these 7 clusters, 21 points belonging to the clusters in the papillomacular region included cluster 5. Cluster 5 was distributed above and below the horizontal meridian, which does not agree with the course of the retinal nerve fiber layer (RNFL).

Conclusion

The hierarchical cluster analysis of the TD values stratified the 68 test points of the 10-2 into seven clusters. Considering the course of the RNFL, cluster 5 was divided into clusters of 5a and 5b, and consequently eight clusters were considered to be appropriate for detecting glaucomatous visual field defects in the central 10 degrees in NTG eyes.