Optometry Commons^™

Biallelic Loss-Of-Function Variants In C19orf44 Lead To Retinal Degeneration, Hafiz Muhammad Jafar Hussain, Wang Meng, Yumei Li, Sabika Firasat, Mark E Pennesi, Michael B Gorin, Bin Guan, Rebecca Lynn Clark, Emma Fale-Olsen, Ranya Al Rawi, Aime Agather, Laryssa A Huryn, Paul Yang, Anna Matynia, Rui Chen

Faculty, Staff and Students Publications

Background: Inherited retinal diseases (IRDs) are a group of disorders often resulting in progressive vision loss, ultimately leading to blindness. A significant portion of their genetic causes remain unresolved, partly due to undiscovered disease-associated genes or variants. This study aimed to identify novel genetic links to IRDs.

Methods: All patients underwent comprehensive ophthalmological evaluation, including retinal imaging (fundus autofluorescence and macular optical coherence tomography) and electroretinogram testing. Whole exome sequencing and whole genome sequencing were performed on patients with clinically unsolved IRD, and data were analysed using an in-house pipeline to identify causal variants. Subsequently, Sanger sequencing was performed to …

Pfkfb3 Connects Glycolytic Metabolism With Endothelial Dysfunction In Human And Rodent Obesity, Robert K Batori, Zsuzsanna Bordan, Caleb A Padgett, Yuqing Huo, Feng Chen, Reem T Atawia, Rudolf Lucas, Masuko Ushio-Fukai, Tohru Fukai, Eric J Belin De Chantemele, David W Stepp, David J R Fulton

Faculty, Staff and Students Publications

Obesity and type 2 diabetes (T2D) increase cardiovascular risk, largely due to altered metabolic state. An early consequence of T2D/obesity is the loss of endothelial function and impaired nitric oxide (NO) signaling. In blood vessels, endothelial nitric oxide synthase (eNOS) synthesizes NO to maintain vessel homeostasis. The biological actions of NO are compromised by superoxide that is generated by NADPH oxidases (NOXs). Herein we investigated how altered metabolism affects superoxide/NO balance in obesity. We found that eNOS expression and NO bioavailability are significantly decreased in endothelial cells (ECs) from T2D patients and animal models of obesity. In parallel, PFKFB3, a …

Optimal Humanized Scg3-Neutralizing Antibodies For Anti-Angiogenic Therapy Of Diabetic Retinopathy, Chengchi Huang, Prabuddha Waduge, Avinash Kaur, Hong Tian, Christina Y Weng, John Timothy Stout, Iok-Hou Pang, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Secretogranin III (Scg3) is a diabetic retinopathy (DR)-restricted angiogenic factor identified in preclinical studies as a target for DR therapy. Previously, our group generated and characterized ML49.3, an anti-Scg3 monoclonal antibody (mAb) which we then converted into an EBP2 humanized antibody Fab fragment (hFab) with potential for clinical application. We also generated anti-Scg3 mT4 mAb and related EBP3 hFab. In this study, to identify the preferred hFab for DR therapy, we compared all four antibodies for binding, neutralizing and therapeutic activities in vitro and in vivo. Octet binding kinetics analyses revealed that ML49.3 mAb, EBP2 hFab, mT4 mAb and EBP3 …

Integrating Genetic Regulation And Single-Cell Expression With Gwas Prioritizes Causal Genes And Cell Types For Glaucoma, Andrew R Hamel, Wenjun Yan, John M Rouhana, Aboozar Monovarfeshani, Xinyi Jiang, Puja A Mehta, Jayshree Advani, Yuyang Luo, Qingnan Liang, Skanda Rajasundaram, Arushi Shrivastava, Katherine Duchinski, Sreekar Mantena, Jiali Wang, Tavé Van Zyl, Louis R Pasquale, Anand Swaroop, Puya Gharahkhani, Anthony P Khawaja, Stuart Macgregor, Rui Chen, Veronique Vitart, Joshua R Sanes, Janey L Wiggs, Ayellet V Segrè

Faculty, Staff and Students Publications

Primary open-angle glaucoma (POAG), characterized by retinal ganglion cell death, is a leading cause of irreversible blindness worldwide. However, its molecular and cellular causes are not well understood. Elevated intraocular pressure (IOP) is a major risk factor, but many patients have normal IOP. Colocalization and Mendelian randomization analysis of >240 POAG and IOP genome-wide association study (GWAS) loci and overlapping expression and splicing quantitative trait loci (e/sQTLs) in 49 GTEx tissues and retina prioritizes causal genes for 60% of loci. These genes are enriched in pathways implicated in extracellular matrix organization, cell adhesion, and vascular development. Analysis of single-nucleus RNA-seq …

Accuracy Of Artificial Intelligence In Estimating Best-Corrected Visual Acuity From Fundus Photographs In Eyes With Diabetic Macular Edema, William Paul, Philippe Burlina, Rohita Mocharla, Neil Joshi, Zhuolin Li, Sophie Gu, Onnisa Nanegrungsunk, Kira Lin, Susan B Bressler, Cindy X Cai, Jun Kong, T Y Alvin Liu, Hadi Moini, Weiming Du, Fouad Amer, Karen Chu, Robert Vitti, Farshid Sepehrband, Neil M Bressler

Faculty, Staff and Students Publications

IMPORTANCE: Best-corrected visual acuity (BCVA) is a measure used to manage diabetic macular edema (DME), sometimes suggesting development of DME or consideration of initiating, repeating, withholding, or resuming treatment with anti-vascular endothelial growth factor. Using artificial intelligence (AI) to estimate BCVA from fundus images could help clinicians manage DME by reducing the personnel needed for refraction, the time presently required for assessing BCVA, or even the number of office visits if imaged remotely.

OBJECTIVE: To evaluate the potential application of AI techniques for estimating BCVA from fundus photographs with and without ancillary information.

DESIGN, SETTING, AND PARTICIPANTS: Deidentified color fundus …

Systemic Adverse Events Among Patients With Diabetes Treated With Intravitreal Anti-Vascular Endothelial Growth Factor Injections, Sidra Zafar, Annette Walder, Salim Virani, Kristin Biggerstaff, Silvia Orengo-Nania, Jonathan Chang, Roomasa Channa

Faculty, Staff and Students Publications

IMPORTANCE: Anti-vascular endothelial growth factor (VEGF) agents are currently the mainstay of treatment for diabetic retinopathy (DR). Although effective, data on their systemic safety remains inconclusive, particularly in high-risk patient groups.

OBJECTIVE: To explore the systemic safety of intravitreal anti-VEGF agents among patients with diabetes.

DESIGN, SETTING, AND PARTICIPANTS: This was a retrospective, longitudinal population-based analysis of the Corporate Data Warehouse, a large-scale database of patients within the US Veteran Health Affairs. All patients 18 years and older with type 2 diabetes who were seen at any Veterans Affairs health care facility in the US between January 1, 2011, and …

Secretogranin Iii Selectively Promotes Vascular Leakage In The Deep Vascular Plexus Of Diabetic Retinopathy, Liyang Ji, Prabuddha Waduge, Yan Wu, Chengchi Huang, Avinash Kaur, Paola Oliveira, Hong Tian, Jinsong Zhang, J Timothy Stout, Christina Y Weng, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Diabetic retinopathy (DR), a leading cause of vision loss in working-age adults, induces mosaic patterns of vasculopathy that may be associated with spatial heterogeneity of intraretinal endothelial cells. We recently reported that secretogranin III (Scg3), a neuron-derived angiogenic and vascular leakage factor, selectively binds retinal vessels of diabetic but not healthy mice. Here, we investigated endothelial heterogeneity of three retinal vascular plexuses in DR pathogenesis and the therapeutic implications. Our unique in vivo ligand binding assay detected a 22.7-fold increase in Scg3 binding to retinal vessels of diabetic mice relative to healthy mice. Functional immunohistochemistry revealed that Scg3 predominantly binds …

Fluorescence Angiography With Dual Fluorescence For The Early Detection And Longitudinal Quantitation Of Vascular Leakage In Retinopathy, Benjamin Pomeroy, Alexander W Venanzi, Wei Li, Abigail S Hackam, Midhat H Abdulreda

Faculty, Staff and Students Publications

BACKGROUND: Diabetic retinopathy (DR) afflicts more than 93 million people worldwide and is a leading cause of vision loss in working adults. While DR therapies are available, early DR development may go undetected without treatment due to the lack of sufficiently sensitive tools. Therefore, early detection is critically important to enable efficient treatment before progression to vision-threatening complications. A major clinical manifestation of early DR is retinal vascular leakage that may progress from diffuse to more localized focal leakage, leading to increased retinal thickness and diabetic macular edema (DME). In preclinical research, a hallmark of DR in mouse models is …

Effect Of The Covid-19 Pandemic Lockdown On The Management Of Diabetic Retinopathy: A Cross-Sectional Study, Vaishali Prajapati, Krishna Shah, Dhruvi Shah, Mayur B Wanjari, Deepika Singhal

Faculty, Staff and Students Publications

Introduction Worldwide, diabetic retinopathy (DR) is one of the leading causes of vision loss. Early treatment and screening for DR have a major role in reducing the rate of the disease and the coronavirus disease 2019 (COVID-19) pandemic-related restrictions have altered real-world practice patterns in managing DR. Aims and objectives To evaluate the impact of the COVID-19 pandemic on the management of DR amongst patients presenting to a tertiary eye care center in Gujarat, India. Methods This is a cross-sectional study comparison of ophthalmic findings of 72 patients who presented to a tertiary care hospital with the manifestation of DR …

Impact Of The Covid-19 Pandemic On Visual Outcomes Of Diabetic Macular Edema Patients At A Tertiary Care Veterans Affairs Center, Philip Zhou, Jie Gao, Xiaofan Huang, Kristen A Staggers, Kristin Biggerstaff, Silvia Orengo-Nania, Roomasa Channa

Faculty, Staff and Students Publications

PURPOSE: There are limited studies on factors that impacted retina clinic patient outcomes during the COVID-19 pandemic. We aimed to evaluate visual and anatomic outcomes in patients with diabetic macular edema (DME) requiring anti-VEGF injections at the veterans' affairs tertiary care eye clinic in Houston, TX.

METHODS: Patient volume from April 2020 was compared to that of April 2019 to determine attendance changes. To evaluate outcomes, we reviewed patients with DME who had scheduled appointments during April 2020. We tracked changes in central foveal thickness (CFT) and Snellen visual acuity (VA) measurements. Patient outcomes were classified as poor (defined as …

Secretogranin Iii Stringently Regulates Pathological But Not Physiological Angiogenesis In Oxygen-Induced Retinopathy, Chang Dai, Prabuddha Waduge, Liyang Ji, Chengchi Huang, Ye He, Hong Tian, Elizabeth Zuniga-Sanchez, Amit Bhatt, Iok-Hou Pang, Guanfang Su, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Conventional angiogenic factors, such as vascular endothelial growth factor (VEGF), regulate both pathological and physiological angiogenesis indiscriminately, and their inhibitors may elicit adverse side effects. Secretogranin III (Scg3) was recently reported to be a diabetes-restricted VEGF-independent angiogenic factor, but the disease selectivity of Scg3 in retinopathy of prematurity (ROP), a retinal disease in preterm infants with concurrent pathological and physiological angiogenesis, was not defined. Here, using oxygen-induced retinopathy (OIR) mice, a surrogate model of ROP, we quantified an exclusive binding of Scg3 to diseased versus healthy developing neovessels that contrasted sharply with the ubiquitous binding of VEGF. Functional immunohistochemistry visualized …

Addressing Artificial Intelligence Bias In Retinal Diagnostics, Philippe Burlina, Neil Joshi, William Paul, Katia D Pacheco, Neil M Bressler

Faculty, Staff and Students Publications

PURPOSE: This study evaluated generative methods to potentially mitigate artificial intelligence (AI) bias when diagnosing diabetic retinopathy (DR) resulting from training data imbalance or domain generalization, which occurs when deep learning systems (DLSs) face concepts at test/inference time they were not initially trained on.

METHODS: The public domain Kaggle EyePACS dataset (88,692 fundi and 44,346 individuals, originally diverse for ethnicity) was modified by adding clinician-annotated labels and constructing an artificial scenario of data imbalance and domain generalization by disallowing training (but not testing) exemplars for images of retinas with DR warranting referral (DR-referable) from darker-skin individuals, who presumably have greater …

Identification Of Deep-Intronic Splice Mutations In A Large Cohort Of Patients With Inherited Retinal Diseases, Xinye Qian, Jun Wang, Meng Wang, Austin D Igelman, Kaylie D Jones, Yumei Li, Keqing Wang, Kerry E Goetz, David G Birch, Paul Yang, Mark E Pennesi, Rui Chen

Faculty, Staff and Students Publications

High throughput sequencing technologies have revolutionized the identification of mutations responsible for a diverse set of Mendelian disorders, including inherited retinal disorders (IRDs). However, the causal mutations remain elusive for a significant proportion of patients. This may be partially due to pathogenic mutations located in non-coding regions, which are largely missed by capture sequencing targeting the coding regions. The advent of whole-genome sequencing (WGS) allows us to systematically detect non-coding variations. However, the interpretation of these variations remains a significant bottleneck. In this study, we investigated the contribution of deep-intronic splice variants to IRDs. WGS was performed for a cohort …

Mtor-Initiated Metabolic Switch And Degeneration In The Retinal Pigment Epithelium, Young-Mi Go, Jing Zhang, Jolyn Fernandes, Christopher Litwin, Rui Chen, Theodore G Wensel, Dean P Jones, Jiyang Cai, Yan Chen

Faculty, Staff and Students Publications

The retinal pigment epithelium (RPE) is a particularly vulnerable tissue to age-dependent degeneration. Over the life span, the RPE develops an expanded endo-lysosomal compartment to maintain the high efficiency of phagocytosis and degradation of photoreceptor outer segments (POS) necessary for photoreceptor survival. As the assembly and activation of the mechanistic target of rapamycin complex 1 (mTORC1) occur on the lysosome surface, increased lysosome mass with aging leads to higher mTORC1 activity. The functional consequences of hyperactive mTORC1 in the RPE are unclear. In the current study, we used integrated high-resolution metabolomic and genomic approaches to examine mice with RPE-specific deletion …

Quality Improvement Initiative To Increase Comprehensive Eye Exams In Patients With Diabetes, Julia Khoury

Doctor of Nursing Practice

Diabetic retinopathy is the most common microvascular complication associated with poorly controlled diabetes. Yet, only 60% of the diabetic population receives an annual eye examination by an eye specialist. Retinal imaging increases surveillance of retinopathy, however, it does not take the place of a comprehensive eye examination by an ophthalmologist or optometrist. The aim of this quality improvement project was to increase comprehensive eye examinations in patients with diabetes aged 18 to 75 years in a family practice that recently purchased a retinal imager. This quality improvement project occurred over a 10-week period. Project objectives included increasing comprehensive dilated eye …