Purpose: Hormonal therapy (HT) has been suggested to lower the risk of developing glaucoma. Our goal was to investigate the association between HT use and the onset of glaucoma diagnosis in postmenopausal women. Methods: This retrospective case-only study included female veterans with open-angle glaucoma from VA records between 2000 to 2019. Propensity score matching was used to match HT (n = 1926) users to untreated (n = 1026) women on multiple covariates (e.g., age of menopause, BMI, blood pressure, antihypertensive medications, and a co-morbidity index). A simple linear regression was used to evaluate the impact of HT duration on the age of glaucoma diagnosis, and multivariate linear regression analysis was used to determine which factors contributed to the age at diagnosis of glaucoma. Results: We found a linear relationship between the age at diagnosis of glaucoma and menopause in women with (r = 0.54) and without HT (r = 0.57) use. HT users tended to have a later diagnosis of glaucoma. Our multivariate analysis found that 0–2 years, 2–5 years, and >5 years of HT use were associated with a 2.20 [confidence interval (CI), 1.64, 2.76], 3.74 [CI, 3.02, 4.46], and 4.51 [CI, 3.84, 5.18] years later diagnosis of glaucoma. An interaction (−0.009 [−0.015, −0.003]) was observed between HT duration and age of menopause diagnosis, with the impact of HT decreasing for later menopause ages. Conclusions: Longer duration of HT use was associated with a later diagnosis of glaucoma in postmenopausal women in this case-only analysis. The impact of HT may be modulated by menopausal age, although further study is needed. The findings support a protective role of estrogen in glaucoma pathogenesis.

The association between 17β-estradiol (E2) deprivation, seen in menopause, and a risk for developing glaucoma has been shown. Thus, exogenous supplementation of E2 may protect against retinal ganglion cell (RGC) degradation and vision loss. Here, we investigated the utility of topical 10β,17β-dihydroxyestra-1,4-dien-3-one (DHED), a prodrug of E2 that selectively produces the neuroprotective hormone in the retina, on visual function after optic nerve crush (ONC) and ovariectomy (OVX). We used female Brown Norway rats that underwent either Sham or OVX surgeries. After ONC, OVX animals received DHED or vehicle eye drops for 12 weeks. Visual function, via the optomotor reflex, and retinal thickness, via optical coherence tomography, were followed longitudinally. Afterward, we performed mass spectrometry-based label-free retina proteomics to survey retinal protein interaction networks in our selected animal model and to identify E2-responsive proteins after OVX on neurodegeneration. We found that ONC with OVX caused a significant decline in visual functions that were ameliorated by DHED treatments. Discovery-driven retina proteomics identified numerous proteins associated with neurodegenerative processes due to ONC that were remediated by DHED eye drops. Altogether, our three-pronged phenotypic preclinical evaluation of the topical DHED in the OVX + ONC model of glaucoma reveals the therapeutic potential of the prodrug to prevent visual deficits after glaucomatous retinal injury.

We present RetOCTNet, a deep learning tool to segment the retinal nerve fiber layer (RNFL) and total retinal thickness automatically from optical coherence tomography (OCT) scans in rats following retinal ganglion cell (RGC) injury. We created unilateral RGC injury by ocular hypertension (OHT) or optic nerve crush (ONC), and contralateral eyes were not injured. We manually segmented the RNFL and total retina of 3.0-mm radial OCT scans (1000 A-scans per B-scan, 20 frames per B-scan) as ground truth (n = 192 scans). We used these segmentations for training (80%), testing (10%), and validation (10%) to optimize the F1 score. To determine the generalizability of RetOCTNet, we tested it on volumetric scans of a separate cohort at baseline and 4, 8, and 12 weeks post-ONC. RetOCTNet's segmentations achieved high F1 scores relative to the ground-truth segmentations created by human annotators: 0.88 (RNFL) and 0.98 (retinal thickness) for control eyes, 0.84 and 0.98 for OHT eyes, and 0.78 and 0.96 for ONC eyes, respectively. On volumetric scans 12 weeks post-ONC, RetOCTNet calculated thinning of 29.49% and 10.82% in the RNFL and retina at the optic nerve head (ONH) and thinning of 38.34% and 9.85% in the RNFL and retina superior to the ONH. RetOCTNet can segment the RNFL and total retinal thickness of both radial and volume OCT scans. RetOCTNet can be applied to longitudinally monitor RNFL in rodent models of RGC injury. This tool automates RNFL and retinal thickness measurement for rat OCT scans following RGC injury, reducing analysis time and increasing the consistency between studies.

Purpose: Age of menopause has been associated with the risk of developing glaucoma; however, it is unclear if the onset of menopause is directly associated with the development of glaucoma. Our objective was to determine if there is an association between the age at diagnosis of menopause and glaucoma. Methods: This retrospective, case-only analysis was performed using the Veterans Affairs (VA) Corporate Data Warehouse of female veterans from 2000 to 2019. Women with both menopause and glaucoma diagnoses were matched based on covariates. The two matched cohorts were early menopause–early comparative (EM-EC; n = 1075) and late menopause–late comparative (LM-LC; n = 1050) women. We used a Pearson correlation to examine the linear relationship between age at diagnosis of menopause and glaucoma. Afterward, we used a multivariate linear regression model with age at diagnosis of glaucoma serving as the outcome variable to account for the covariates. Results: We found that EM women developed glaucoma 6.0 years (interquartile range [IQR], 5.1–6.5) earlier than the EC group (P < 0.001), and LM women developed glaucoma an average of 5.2 years (IQR, 4.8–5.7) later than the LC group (P < 0.001). There was a modest linear relationship between the age of menopause and glaucoma diagnoses in the EM-EC (r = 0.40) and LM-LC (r = 0.46) cohorts. In our multivariate analysis, age at diagnosis of menopause was the largest factor related to age at diagnosis of glaucoma while accounting for our covariates. Our models predicted a 0.67-year delay in age at diagnosis of glaucoma with each additional premenopausal year. Conclusions: This case-only analysis elucidates a temporal association between menopause and glaucoma, highlighting the need to characterize the role of menopause in the onset of glaucoma for women.

Increased risk of developing glaucoma has recently been associated with early age of menopause. Here, we examined how age and surgically-induced menopause via ovariectomy (OVX) impacted gene expression in gene pathways previously linked to glaucoma, such as extracellular matrix (ECM) remodeling and TGF-β signaling. Using bulk RNA sequencing, we analyzed changes in young (3-4 months) and middle-aged (9-10 months) Long-Evans rats. We focused on posterior pole tissues (sclera and optic nerve head) but also examined the retina to compare observed changes across different tissue regions. Our results demonstrated that aging and OVX significantly alter gene expression in the sclera and optic nerve head. Generally, OVX triggered the enrichment of immune-related processes. However, OVX in young rats also led to significant enrichment of ECM and TGF-β gene sets. At the same time, these effects were diminished in middle-aged rats, indicating an age dependency of the effects of OVX on matrix-related pathways. Notably, the transcriptional factor Fos was downregulated in the posterior eye and retina in aged and OVX animals. Fos is a major regulator of cell proliferation and survival, and its dysregulation may play an important role in aging and menopause for women. These findings underscore the important role of menopause timing in modulating molecular pathways associated with glaucoma, which is consistent with clinical studies showing that early menopause may heighten the risk of developing this condition. This study also highlights the importance of considering women's health factors, such as menopause, in understanding and managing glaucoma risk.

Purpose: Electroretinography (ERG) is used to assess retinal function in ophthalmology clinics and animal models of ocular disease; however, analyzing ERG waveforms can be a time-intensive process with interobserver variability. We developed ERGAssist, an automated approach, to perform non-subjective and repeatable feature identification (“marking”) of the ERG waveform. Methods: The automated approach denoised the recorded waveforms and then located the b-wave after applying a lowpass filter. If an a-wave was present, the lowpass filter wave was also used to help locate the a-wave, which was considered the initial large negative response after the flash stimuli. Oscillatory potentials (OPs) were found using a bandpass filter on the denoised waveform. We used two cohorts. One was a Coherence cohort that consisted of ERGs with eight dark-adapted and three light-adapted stimuli in Brown Norway rats (−6 to 1.5 log cd·s/m²). The Verification cohort consisted of control and diabetic (DM) Long Evans rats. We examined retinal function using a five-step dark-adapted protocol (−3 to 1.9 log cd·s/m²). Results: ERGAssist showed a strong correlation with manual markings of ERG features in our Coherence dataset, including the amplitudes (a-wave: r² = 0.99; b-wave: r² = 0.99; OP: r² = 0.92) and implicit times (a-wave: r² = 0.96; b-wave: r² = 0.90; OP: r² = 0.96). In the Verification cohort, both approaches detected differences between control and DM animals and found longer OP implicit times (P < 0.0001) in DM animals. Conclusions: These results provide verification of ERGAssist to identify features of the full-field ERG. Translational Relevance: This ERG analysis approach can increase the rigor of basic science studies designed to investigate retinal function using full-field ERG. To aid the community, we have developed an open-source graphical user interface (GUI) implementing the methods presented.