Current Initiatives & Research Interests
How to Get Involved
From the patients in Miami to the physicians and researchers in Seattle, all stakeholders involved in secondary glaucoma can unite to achieve the strength of numbers. The first step in this endeavor is to collect data on disease prevalence across clinics in the United States. If you are a representative of an ophthalmology/optometry clinic, please complete the following survey to join the network!
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By scrolling below, you may view our current research and advocacy interests in secondary glaucoma, illustrating our first projects in expanding our current state of knowledge and building our community.
Pseudoexfoliation and Pigment Dispersion
Pseudoexfoliative glaucoma (PEXG) results from pseudoexfoliation syndrome (PEX), in which fibrillary, flake-like particles deposit intra- and extra-ocularly. Intraocularly, these fibrillary particles hinder the outflow of aqueous humor at the trabecular meshwork. About 25-50% of patients with PEX develop elevated intraocular pressure and ~30% of these individuals develop glaucoma. PEXG affects about 20% of the population with open-angle secondary glaucoma [1]. Elevated intraocular pressure damages the optic nerve head and retinal ganglion layer. Currently it is thought that the LOXL-1, the FBLN5 gene, and the clusterin protein have roles in PEX development [2]. Non-genetic factors including geographical latitude, solar radiation, and dietary intake also contribute to PEX onset [3]. Complete understanding of the genetic and environmental factors that contribute to the development of PEX and PEXG remains an open research question. A recent study has shown that the metabolites in the aqueous humor of PEXG patients are distinctive [4], which could aid in the diagnosis, prognosis, and treatment of PEXG.
Pigmentary dispersion syndrome (PDS) is characterized by the deposition of pigment granules from the iris pigment epithelium to the anterior segment of the eye. These deposits block aqueous humor outflow at the trabecular meshwork which leads to pigmentary dispersion glaucoma (PDG). PDS seems to be associated with PEX [1], though the genetic contribution to PDS is complex and further studies are needed. Interestingly, it is thought that larger eye configuration (e.g. in individuals with myopia) increases iridozonular friction and pigmentary dispersion [1]. Histopathologically, the iris pigment epithelium in individuals with PDS or PDG has focal atrophy, hypopigmentation, and delayed melanogenesis [5]. The mean onset of PDG in men and women is 35 years old and 46 years old respectively, and PDG affects men:women at a 3:1 ratio [1]. The risk of PDG developing from pigmentary dispersion syndrome (PDS) is 10% at 5 years and 15% at 15 years [6]. There is a decreased incidence of PDG with age, and the disease may even regress. However, the vision damage from glaucoma is irreversible, and prompt diagnosis and therapy early on is crucial in preventing progression of the disease.
Numerous questions have yet to be answered in order to advance the diagnostic, preventative, and therapeutic modalities for PEXG and PDG. Our goal is to aggregate data from ophthalmology clinics that treat PEX and PDG and pertinent information from individuals with PEXG and PDG from all 50 states. The information collected will be used to support future PEXG and PDG studies.​
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1. Yanoff, M., & Duker, J. S. (2019). Ophthalmology. Elsevier.
2. Morris, J. et al. (2021). Proteomics of pseudoexfoliation materials in the anterior eye segment. Advances in Protein Chemistry and Structural Biology.
3. Dewundara, S., & Pasquale, L. R. (2015). Exfoliation syndrome: a disease with an environmental component. Current Opinion in Ophthalmology, 26(2), 78–81.
4. Myer, C. et al. (2020). Aqueous humor metabolite profile of pseudoexfoliation glaucoma is distinctive. Molecular Omics, 16(5), 425–435.
5. Kupfer, C., Kuwabara, T., & Kaiser-Kupfer, M. (1975). The Histopathology of Pigmentary Dispersion Syndrome with Glaucoma. American Journal of Ophthalmology, 80(5), 857–862.
6. Siddiqui, Y. et al. (2003). What is the risk of developing pigmentary glaucoma from pigment dispersion syndrome? American Journal of Ophthalmology, 135(6), 794–799.
Secondary Glaucoma and Dyslipidemia
We postulate that certain cholesterol-lowering medications are associated with increased intraocular pressure in secondary glaucoma. In the initial phase, we will use this site to build a database of clinics with relevant patients, and we will plan to conduct survey-based research with participants to characterize prevalence and correlation.
Pediatric Occurrence of Secondary Glaucoma
Although pigmentary dispersion and pseudoexfoliation syndrome are most commonly found in middle-aged and elderly populations, we seek to understand why they sometimes present in children. We postulate that pediatric occurrence represents a more aggressive and severe form of disease that may merit unique attention and treatment. Our first phase involves collecting pediatric prevalence data from participating clinics.
