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The main objective of this placebo-controlled, triple-blind, balanced crossover study was to assess the acute effects of phenylcapsaicin (PC) intake (2.5 mg) on intraocular pressure (IOP), ocular perfusion pressure (OPP), and heart rate (HR) during a 30-min cycling task performed at 15% of the individual maximal power. Twenty-two healthy young adults performed the cycling task 45 min after ingesting PC or placebo. IOP was measured with a rebound tonometer before exercise, during cycling (every 6 min), and after 5 and 10 min of recovery. OPP was assessed before and after exercise. HR was monitored throughout the cycling task. We found an acute increase of IOP levels related to PC consumption while cycling (mean difference = 1.91 ± 2.24 mmHg; p =.007, η p 2 =.30), whereas no differences were observed for OPP levels between the PC and placebo conditions (mean difference = 1.33 ± 8.70 mmHg; p =.608). Mean HR values were higher after PC in comparison with placebo intake (mean difference = 3.11 ± 15.87 bpm, p =.019, η p 2 =.24), whereas maximum HR did not differ between both experimental conditions (p =.199). These findings suggest that PC intake before exercise should be avoided when reducing IOP levels is desired (e.g., glaucoma patients or those at risk). Future studies should determine the effects of different ergogenic aids on IOP and OPP levels with other exercise configurations and in the long term. [ABSTRACT FROM AUTHOR]

BACKGROUND: Intraocular pressure (IOP) monitoring in glaucoma management is evolving with novel devices. We investigated the reproducibility of 24 hour profiles on two consecutive days and after 30 days of self-measurements via telemetric IOP monitoring. METHODS: Seven primary patients with open-angle glaucoma previously implanted with a telemetric IOP sensor in one eye underwent automatic measurements throughout 24 hours on two consecutive days (day 1 and day 2). Patients wore an antenna adjacent to the study eye connected to a reader device to record IOP every 5 min. Also, self-measurements in six of seven patients were collected for a period of 30 days. Analysis included calculation of hourly averages to correlate time-pairs of day 1 versus day 2 and the self-measurements vers day 2. RESULTS: The number of IOP measurements per patient ranged between 151 and 268 on day 1, 175 and 268 on day 2 and 19 and 1236 during 30 days of self-measurements. IOP time-pairs of automatic measurements on day 1 and day 2 were significantly correlated at the group level (R=0.83, p

Glaucoma, an optic neuropathy with the loss of retinal ganglion cells (RGCs), is a leading cause of irreversible vision loss. Oxidative stress and mitochondrial dysfunction have a significant role in triggering glia-driven neuroinflammation and subsequent glaucomatous RGC degeneration in the context of glaucoma. It has previously been shown that apolipoprotein A-I binding protein (APOA1BP or AIBP) has an anti-inflammatory function. Moreover, Apoa1bp-/- mice are characterized by retinal neuroinflammation and RGC loss. In this study, we found that AIBP deficiency exacerbated the oxidative stress-induced disruption of mitochondrial dynamics and function in the retina, leading to a further decline in visual function. Mechanistically, AIBP deficiency-induced oxidative stress triggered a reduction in glycogen synthase kinase 3β and dynamin-related protein 1 phosphorylation, optic atrophy type 1 and mitofusin 1 and 2 expression, and oxidative phosphorylation, as well as the activation of mitogen-activated protein kinase (MAPK) in Müller glia dysfunction, leading to cell death and inflammatory responses. In vivo, the administration of recombinant AIBP (rAIBP) effectively protected the structural and functional integrity of retinal mitochondria under oxidative stress conditions and prevented vision loss. In vitro, incubation with rAIBP safeguarded the structural integrity and bioenergetic performance of mitochondria and concurrently suppressed MAPK activation, apoptotic cell death, and inflammatory response in Müller glia. These findings support the possibility that AIBP promotes RGC survival and restores visual function in glaucomatous mice by ameliorating glia-driven mitochondrial dysfunction and neuroinflammation.

PURPOSE: This study uses deep neural network-generated rim-to-disc area ratio (RADAR) measurements and the disc damage likelihood scale (DDLS) to measure the rate of optic disc rim loss in a large cohort of glaucoma patients. METHODS: A deep neural network was used to calculate RADAR and DDLS for each optic disc photograph (ODP). Patient demographics, diagnosis, intraocular pressure (IOP), and mean deviation (MD) from perimetry were analyzed as risk factors for faster progression of RADAR. Receiver operating characteristic (ROC) curves were used to compare RADAR and DDLS in their utility to distinguish glaucoma from glaucoma suspect (GS) and for detecting glaucoma progression. RESULTS: A total of 13,679 ODPs with evidence of glaucomatous optic nerve damage from 4106 eyes of 2407 patients with glaucoma or GS were included. Of these eyes, 3264 (79.5%) had a diagnosis of glaucoma, and 842 (20.5%) eyes were GS. Mean ± SD baseline RADAR of GS and glaucoma were 0.67 ± 0.13 and 0.57 ± 0.18, respectively (P < 0.001). Older age, greater IOP fluctuation, baseline MD, right eye, and diagnosis of secondary open-angle glaucoma were associated with slope of RADAR. The mean baseline DDLS of GS and glaucoma were 3.78 and 4.39, respectively. Both RADAR and DDLS showed a less steep slope in advanced glaucoma. In glaucoma, the change of RADAR and DDLS correlated with the corresponding change in MD. RADAR and DDLS had a similar ability to discriminate glaucoma from GS and detect disease progression. Area under the ROC curve of RADAR and DDLS was 0.658 and 0.648. CONCLUSIONS: Automated calculation of RADAR and DDLS with a neural network can be used to evaluate the extent and long-term rate of optic disc rim loss and is further evidence of long-term nerve fiber loss in treated patients with glaucoma. TRANSLATIONAL RELEVANCE: Our study provides a large clinic-based experience for RADAR and DDLS measurements in GS and glaucoma with a neural network.

PURPOSE: To evaluate Humphrey Visual Field (HVF) test reliability and its associated risk factors in children with glaucoma or glaucoma suspect. DESIGN: Retrospective cohort study. METHODS: None. SETTING: Single-center childhood glaucoma clinic. PATIENT POPULATION: One hundred thirty-six patients aged ≤18 years with glaucoma/glaucoma suspect, and least 1 completed 24 to 2 HVF test between 2018 and 2023. OBSERVATION PROCEDURE: Demographic and clinical characteristics including age, primary language, visual acuity (VA), and glaucoma diagnosis were extracted from electronic health records. MAIN OUTCOME MEASURES: HVF 24 to 2 testing metrics, including FP, FN, and FL. Tests were defined as reliable using manufacturer guidelines of ≤33% FP, ≤33% FN, and ≤20% FL. For each patient, a reliability score was calculated as the percentage of reliable tests among all tests completed. A multivariable logistic regression model was used to determine factors associated with test-level reliability (yes/no). A multivariable linear regression model was used to determine factors associated with patient-level reliability score. RESULTS: Among 634 HVFs from 136 patients (Mean ± SD age at first test 12.0 ± 3.2 years, 47.8% female), 51.3% were reliable. Older age, better baseline VA, and English as primary language were associated with greater odds of test-level reliability (P < .04). Mean ± SD patient-level reliability score was 51.7 ± 38.1%. Older age at first clinic visit, better baseline VA, and English as primary language were associated with higher reliability scores (all P < .02), and number of prior VF tests was not (P = .56). CONCLUSIONS: Younger age, worse visual acuity, and non-English as primary language were associated with decreased reliability and should be considered when interpreting VF testing in children. A significant learning effect was not observed with repeated testing.

BackgroundTo examine long-term retinal nerve fibre layer thickness (RNFLT) variability and associated clinical factors in African (AD) and European descent (ED) individuals with glaucoma.MethodsThis retrospective cohort study included glaucoma eyes of AD and ED from Diagnostic Innovations in Glaucoma Study/The African Descent and Glaucoma Evaluation Study with ≥4 visits/2 years of follow-up. We calculated optic nerve head RNFLT variability per-examination/visit as the absolute error of its residuals across follow-up. Full, baseline and parsimonious linear-mixed models were fit to evaluate the effects of clinical factors (demographics and ocular characteristics, prior/intervening glaucoma surgeries and cataract extraction (CE), RNFLT thinning rate, scan quality, visit/testing frequency, etc) on RNFLT variability in both races.ResultsThere were 376 and 625 eyes (226 and 349 participants) of AD and ED, and the mean (95% CI) RNFLT variability was 1.62 (1.52, 1.71) µm and 1.42 (1.34, 1.50) µm, respectively (p=0.002). AD and ED had some shared predictors of RNFLT variability, including intraocular pressure fluctuation and scan quality, although the effects varied (p

Background/aimsTo investigate the association between longitudinal changes of foveal avascular zone (FAZ) area and the rate of structural and functional progression in glaucoma.MethodsA longitudinal cohort included 115 eyes (46 glaucoma suspect and 66 primary open-angle glaucoma) of 81 patients having ≥2 year follow-up, and ≥4 visits with optical coherence tomography angiography and visual field (VF). Eyes in the longitudinal cohort with a slope greater than that found in 95 percentile of separate healthy test-retest series for FAZ area were categorised into FAZ progressors; all other eyes were defined as FAZ non-progressors. A generalised linear mixed-effect model was used to investigate the association of FAZ progressors with demographic and clinical characteristics.ResultsFaster ganglion cell complex (GCC) thinning and faster VF mean deviation (MD) loss were found in eyes with FAZ progressors compared with FAZ non-progressors (mean difference: -0.7 (95% CI, -1.4 to -0.1) µm/y; p=0.026, -0.3 (-0.5 to -0.1) dB/y; p=0.017, respectively), while whole image vessel density was not associated with FAZ progressors (p=0.929). SD of intraocular pressure (IOP) and IOP range were also associated with FAZ progressors in separate multivariable models (OR: 1.54 (1.02 to 2.32) per 1 mm Hg higher, p=0.041; OR: 1.20 (1.01 to 1.41) per 1 mm Hg higher; p=0.035, respectively).ConclusionsSignificant FAZ increase was weakly associated with moderately faster rates of both GCC thinning and VF MD loss, but not macular vessel density change in glaucoma eyes. Additional studies are needed to elucidate the pathophysiological associations between macula GCC thinning and FAZ area increases in glaucoma.

AIM: We tested the hypothesis that visual field (VF) progression can be predicted with a deep learning model based on longitudinal pairs of optic disc photographs (ODP) acquired at earlier time points during follow-up. METHODS: 3919 eyes (2259 patients) with ≥2 ODPs at least 2 years apart, and ≥5 24-2 VF exams spanning ≥3 years of follow-up were included. Serial VF mean deviation (MD) rates of change were estimated starting at the fifth visit and subsequently by adding visits until final visit. VF progression was defined as a statistically significant negative slope at two consecutive visits and final visit. We built a twin-neural network with ResNet50-backbone. A pair of ODPs acquired up to a year before the VF progression date or the last VF in non-progressing eyes were included as input. Primary outcome measures were area under the receiver operating characteristic curve (AUC) and model accuracy. RESULTS: The average (SD) follow-up time and baseline VF MD were 8.1 (4.8) years and -3.3 (4.9) dB, respectively. VF progression was identified in 761 eyes (19%). The median (IQR) time to progression in progressing eyes was 7.3 (4.5-11.1) years. The AUC and accuracy for predicting VF progression were 0.862 (0.812-0.913) and 80.0% (73.9%-84.6%). When only fast-progressing eyes were considered (MD rate < -1.0 dB/year), AUC increased to 0.926 (0.857-0.994). CONCLUSIONS: A deep learning model can predict subsequent glaucoma progression from longitudinal ODPs with clinically relevant accuracy. This model may be implemented, after validation, for predicting glaucoma progression in the clinical setting.

PurposeTo compare rates of retinal nerve fiber layer change over time in healthy, eyes with nonprogressing glaucoma and eyes with progressing glaucoma using single wide-field (SWF) and optic nerve head (ONH) cube scan optical coherence tomography (OCT) images.MethodsForty-five eyes of 25 healthy individuals and 263 eyes of 161 glaucoma patients from the Diagnostic Innovations in Glaucoma Study were included. All eyes underwent 24-2 visual field testing and OCT (Spectralis SD-OCT) ONH and macular imaging. SWF images (up to 43° × 28°) were created by stitching together ONH cube scans centered on the optic disc and macular cube scans centered on the fovea. Visual field progression was defined as guided progression analysis likely progression and/or a significant (P < 0.01) mean deviation slope of less than -1.0 dB/year. Mixed effects models were used to compare rates of change. Highly myopic eyes were included.ResultsThirty glaucomatous eyes were classified as progressing. In eyes with glaucoma, mean global rate of change was -1.22 µm/year (P < 0.001) using SWF images and -0.83 µm/year (P = 0.003) using ONH cube scans. Rate of change was significantly greater in eyes with progressing glaucoma compared with eyes with nonprogressing glaucoma (-1.51 µm/year vs. -1.24 µm/year; P = 0.002) using SWF images and was similar using ONH cube scans (P = 0.27).ConclusionsIn this cohort that includes eyes with and without high axial myopia, the mean rate of retinal nerve fiber layer thinning measured using SWF images was faster in eyes with progressing glaucoma than in eyes with nonprogressing glaucoma. Wide-field OCT images including the ONH and macula can be effective for monitoring glaucomatous progression in patients with and without high myopia.

PurposeTo assess the feasibility and performance of Vivid Vision Perimetry (VVP), a new virtual reality (VR)-based visual field platform.MethodsChildren 7-18 years of age with visual acuity of 20/80 or better undergoing Humphrey visual field (HVF) testing were recruited to perform VVP, a VR-based test that uses suprathreshold stimuli to test 54 field locations and calculates a fraction seen score. Pearson correlation coefficients were calculated to evaluate correlation between HVF mean sensitivity and VVP mean fraction seen scores. Participants were surveyed regarding their experience.ResultsA total of 37 eyes of 23 participants (average age, 12.9 ± 3.1 years; 48% female) were included. All participants successfully completed VVP testing. Diagnoses included glaucoma (12), glaucoma suspect (7), steroid-induced ocular hypertension (3), and craniopharyngioma (1). Sixteen participants had prior HVF experience, and none had prior VVP experience, although 7 had previously used VR. Of the 23 HVF tests performed, 9 (39%) were unreliable due to fixation losses, false positives, or false negatives. Similarly, 35% of VVP tests were unreliable (as defined by accuracy of blind spot detection). Excluding unreliable HVF tests, the correlation between HVF average mean sensitivity and VVP mean fraction seen score was 0.48 (P = 0.02; 95% CI, 0.09-0.74). When asked about preference for the VVP or HVF examination, all participants favored the VVP, and 70% were "very satisfied" with VVP.ConclusionsIn our cohort of 23 pediatric subjects, VVP proved to be a clinically feasible VR-based visual field testing, which was uniformly preferred over HVF.