METTL23 Variants and Patients With Normal-Tension Glaucoma.

Importance: This research confirms and further establishes that pathogenic variants in a fourth gene, METTL23, are associated with autosomal dominant normal-tension glaucoma (NTG). Objective: To determine the frequency of glaucoma-causing pathogenic variants in the METTL23 gene in a cohort of patients with NTG from Iowa. Design, Setting, and Participants: This case-control study took place at a single tertiary care center in Iowa from January 1997 to January 2024, with analysis occurring between January 2023 and January 2024. Two groups of participants were enrolled from the University of Iowa clinics: 331 patients with NTG and 362 control individuals without glaucoma. Patients with a history of trauma; steroid use; stigmata of pigment dispersion syndrome; exfoliation syndrome; or pathogenic variants in MYOC, TBK1, or OPTN were also excluded. Main Outcomes and Measures: Detection of an enrichment of METTL23 pathogenic variants in individuals with NTG compared with control individuals without glaucoma. Results: The study included 331 patients with NTG (mean [SD] age, 68.0 [11.7] years; 228 [68.9%] female and 103 [31.1%] male) and 362 control individuals without glaucoma (mean [SD] age, 64.5 [12.6] years; 207 [57.2%] female and 155 [42.8%] male). There were 5 detected instances of 4 unique METTL23 pathogenic variants in patients with NTG. Three METTL23 variants-p.Ala7Val, p.Pro22Arg, and p.Arg63Trp-were judged to be likely pathogenic and were detected in 3 patients (0.91%) with NTG. However, when all detected variants were evaluated with either mutation burden analysis or logistic regression, their frequency was not statistically higher in individuals with NTG than in control individuals without glaucoma (1.5% vs 2.5%; P = .27). Conclusion and Relevance: This investigation provides evidence that pathogenic variants in METTL23 are associated with NTG. Within an NTG cohort at a tertiary care center, pathogenic variants were associated with approximately 1% of NTG cases, a frequency similar to that of other known normal-tension glaucoma genes, including optineurin (OPTN), TANK-binding kinase 1 (TBK1), and myocilin (MYOC). The findings suggest that METTL23 pathogenic variants are likely involved in a biologic pathway that is associated with glaucoma that occurs at lower intraocular pressures.

Eyes for Ears: Usage and Efficacy of a Podcast for Ophthalmic Education.

Purpose: To characterize listenership and perceived educational impact of the ophthalmic podcast "Eyes for Ears". Methods: A cross-sectional, internet-distributed, 9-question Qualtrics survey was made available to podcast listeners. Listenership metrics were analyzed from the podcast host platform. Results: From January 10, 2019 to September 2, 2021, the podcast was downloaded over 422,000 times, averaging about 4442 downloads per episode. 209 Qualtrics survey responses were analyzed from podcast listeners with backgrounds in eye care including medical students, residents, fellows, clinicians and technicians. The majority were residents (60.3%), representative of the target audience of the podcast. Listeners reported using the podcast while commuting (81.3%), felt it increased the time they could spend on self-care (63.2%), and thought it improved their fund of knowledge (99.0%). Respondents recalled feeling better prepared for the OKAP or written boards after using this podcast (before median = 50/100 on Likert Scale, IQR 30-65 vs median = 70/100, IQR 56-81, p <0.001). Respondents identified question banks as the most helpful for OKAP studying, followed by podcasts. Podcasts were preferred over articles and lectures in terms of helpfulness (p < 0.001). Conclusion: The Eyes for Ears podcast has achieved a robust international audience. The surveyed audience felt the podcast was useful for their education and well-being.

Cell-Matrix Interactions in the Eye: From Cornea to Choroid.

The extracellular matrix (ECM) plays a crucial role in all parts of the eye, from maintaining clarity and hydration of the cornea and vitreous to regulating angiogenesis, intraocular pressure maintenance, and vascular signaling. This review focuses on the interactions of the ECM for homeostasis of normal physiologic functions of the cornea, vitreous, retina, retinal pigment epithelium, Bruch's membrane, and choroid as well as trabecular meshwork, optic nerve, conjunctiva and tenon's layer as it relates to glaucoma. A variety of pathways and key factors related to ECM in the eye are discussed, including but not limited to those related to transforming growth factor-ß, vascular endothelial growth factor, basic-fibroblastic growth factor, connective tissue growth factor, matrix metalloproteinases (including MMP-2 and MMP-9, and MMP-14), collagen IV, fibronectin, elastin, canonical signaling, integrins, and endothelial morphogenesis consistent of cellular activation-tubulogenesis and cellular differentiation-stabilization. Alterations contributing to disease states such as wound healing, diabetes-related complications, Fuchs endothelial corneal dystrophy, angiogenesis, fibrosis, age-related macular degeneration, retinal detachment, and posteriorly inserted vitreous base are also reviewed.

Oral rifampin for central serous retinopathy: a strategic approach in three patients.

The authors present three cases of chronic central serous retinopathy in which rifampin was used for the utility of its oral delivery in remote care and as an alternative to photodynamic therapy when intravenous access was not possible. In each of these cases, a reduction of subfoveal fluid and improvement of visual acuity were achieved.

Angioarchitectural evolution of clival dural arteriovenous fistulas in two patients.

Dural arteriovenous fistulas (dAVFs) may present in a variety of ways, including as carotid-cavernous sinus fistulas. The ophthalmologic sequelae of carotid-cavernous sinus fistulas are known and recognizable, but less commonly seen is the rare clival fistula. Clival dAVFs may have a variety of potential anatomical configurations but are defined by the involvement of the venous plexus just overlying the bony clivus. Here we present two cases of clival dAVFs that most likely evolved from carotid-cavernous sinus fistulas.

A Female Patient with Down Syndrome and Low-Penetrance Leber's Hereditary Optic Neuropathy.

We present the case of a 19-year-old female with a history of Down syndrome (DS) who was referred to our neuro-ophthalmology clinic for evaluation of Leber's hereditary optic neuropathy (LHON). The patient's family history was significant for a known G11778A mutation in a maternal relative, consistent with LHON. The patient was also positive for the G11778A mutation; however, the genotype demonstrated low penetrance in the pedigree, with only 1 out of 10 adult male offspring showing signs or symptoms of the disease. Mitochondrial mutations implicated in LHON have been shown to impair complex I of the electron transport chain and thereby reducing the effective generation of adenosine triphosphate and increasing the production of toxic reactive oxygen species. Although the partial or complete triplicate of chromosome 21 constitutes the etiology of DS, some of the pleiotropic phenotypes of the syndrome have been attributed to oxidative stress and mitochondrial dysfunction. Given the low penetrance of the mutation and the patient's sex, this case illustrates the possibility that the mitochondrial mutation demonstrated increased penetrance due to pre-existing mitochondrial dysfunction related to DS.