Purpose: Accumulating evidence suggests that neuroinflammation and immune response are part of the sequence of pathological events leading to optic nerve damage in glaucoma. Changes in tissue temperature due to inflammation can be measured by thermographic imaging. We investigated the ocular surface temperature (OST) profile of glaucomatous eyes to better understand the pathophysiology of these conditions. Methods: Subjects diagnosed with glaucoma (primary open angle glaucoma [POAG] or pseudo exfoliation glaucoma [PXFG]) treated at the Sam Rothberg Glaucoma Center (11/2019–11/2020.) were recruited. Healthy subjects with no ocular disease served as controls. The Therm-App thermal imaging camera was used for OST acquisition. Room and body temperatures were recorded, and the mean temperatures of the medial cantus, lateral cantus, and cornea were calculated with image processing software. Results: Thermographic images were obtained from 52 subjects (52 eyes: 25 POAG and 27 PXFG) and 66 controls (66 eyes). Eyes with glaucoma had a significantly higher OST compared to controls (mean 0.9 ± 0.3°C, p < 0.005). The difference between the two groups remained significant after adjustment for age, sex, intraocular pressure (IOP) and room and body temperatures. Lens status and topical IOP-lowering medication did not significantly affect OST. A subgroup analysis revealed that the OST was higher among eyes with POAG compared to eyes with PXFG, but not significantly. Conclusions: Differences in the OST between glaucomatous and normal eyes strengthens current thinking that inflammation affects the pathophysiology of glaucoma. Longitudinal studies are warranted to establish the prognostic value of thermographic evaluations in these patients.

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Precis: Visual field (VF) endpoints based on average deviation of specific subsets of points rather than all points may offer a more homogeneous data set without necessarily worsening test-retest variability and so may be useful in clinical trials. Purpose: The purpose of this study was to characterize the outcome measures encompassing particular subsets of VF points and compare them as obtained with Humphrey [Humphrey visual field analyser (HVF)] and Compass perimeters. Methods: Thirty patients with imaging-based glaucomatous neuropathy performed a pair of 24-2 tests with each of 2 perimeters. Nonweighted mean deviation (MD) was calculated for the whole field and separate vertical hemifields, and again after censoring of points with low sensitivity (MDc) and subsequently including only “abnormal” points with a total deviation probability of <5% (MDc5%) or <2% (MDc2%). Test-retest variability was assessed using Bland-Altman 95% limits of agreement (95%LoA). Results: For the whole field, using HVF, MD was −7.5±6.9 dB, MDc −3.6±2.8 dB, MDc5% −6.4±1.7 dB, and MDc2% −7.3±1.5 dB. With Compass the MD was −7.5±6.6, MDc −2.9±1.7 dB, MDc5% −6.3±1.5, and MDC2% −7.9±1.6. The respective 95%LoA were 5.5, 5.3, 4.6, and 5.6 with HVF, and 4.8, 3.7, 7.1, and 7.1 with Compass. The respective number of eligible points were 52, 42±12, 20±11, and 15±9 with HVF, and 52, 41.2±12.6, 10±7, and 7±5 with Compass. With both machines, SD and 95%LoA increased in hemifields compared with the total field, but this increase was mitigated after censoring. Conclusion: Restricting analysis to particular subsets of points of interest in the VF after censoring points with low sensitivity, as compared with using the familiar total field MD, can provide outcome measures with a broader range of MD, a markedly reduced SD and therefore more homogeneous data set, without necessarily worsening test-retest variability.