Evaluation of Objective Perimetry Using Chromatic Multifocal Pupillometer
Retinal DystrophiesRetinitis Pigmentosa1 moreObjective perimetry can better monitor visual field defects in retinal dystrophy and Glaucoma patients than conventional subjective perimetry. The PLR ( Pupil Light Reflex to short and long wavelength stimuli should be significantly lower compared to healthy participants in areas of visual field defects in retinal dystrophy and Glaucoma patients.
Matching Glaucoma With Impaired Cognition
Morbidity of Primary Open Angle GlaucomaGlaucoma is the leading cause of irreversible blindness in the world. The current study is designed to find the underlying relationship between impairment of topological perception and incidence of glaucoma.
Glaucoma, Visual Field Loss, and Their Association With Life Space in Older Adults
Primary Open Angle GlaucomaMobility refers to a person's purposeful movement through the environment from one place to another and can be conceptualized as a continuum from bed bound (immobility) on one extreme to making excursions to distant locations on the other extreme. Primary open-angle glaucoma (POAG) is a chronic, progressive optic neuropathy that can lead to gradual loss of vision in the peripheral field and central vision. Older adults with POAG have an increased risk for motor vehicle collisions and falls. Moreover, existing studies suggest that patients with POAG exhibit more postural sway while standing as measured by a balance platform and also tend to walk more slowly than those who are normally sighted and free of ocular disease. While these disturbances likely influence mobility, there has been little research directly assessing the impact of POAG on mobility. This study will assess the impact of POAG on life space (one aspect of mobility) and will determine whether difficulties with life space are associated with difficulties experienced under conditions of dim lighting.
Metformin as a Neuroprotective Therapy for Glaucoma - A Randomized Controlled Trial
GlaucomaGlaucoma, a chronic degenerative disease of the optic nerve, is the leading cause of irreversible blindness worldwide. Although lowering the intraocular pressure (IOP) has been shown to be effective to slow optic nerve degeneration, a significant portion of glaucoma patients continue to develop progressive loss in vision despite adequate control of IOP. Development of neuroprotective therapy to prevent optic nerve degeneration by mechanisms other than IOP- lowering is critical to reduce the burden of glaucoma blindness. With 76 million glaucoma patients in 2020 worldwide, the need to investigate neuroprotection for glaucoma is pressing. While metformin is a widely adopted oral hypoglycemic medication for treatment of type 2 diabetes mellitus (DM), increasing evidence from clinical studies has shown that metformin can decrease the risk of many age-related diseases including neurodegenerative diseases. In a retrospective study of 150,016 patients with DM, those taking metformin at >1500mg/day had a 25% reduced risk of development of open-angle glaucoma than those who took no metformin. Metformin has a high safety profile. We aim to investigate whether metformin can be repurposed to a neuroprotective therapy for glaucoma patients in a randomized controlled trial. We propose to conduct a 24-month, double-blind, placebo-controlled, parallel group, multi- center trial, randomizing 240 primary open angle glaucoma patients who have progressive retinal nerve fiber layer ganglion cell inner plexiform layer (RNFL-GCIPL) thinning in at least one eye, as determined by wide-field optical coherence tomography Trend-based Progression Analysis, to receive metformin 1500mg/day or placebo. All patients will be followed up at 2- month intervals for IOP, RNFL-GCIPL thickness, and visual field (VF) measurements. The objectives are to compare (1) the rates of change of average RNFL-GCIPL thickness (primary outcome measure), and (2) the rates of change of VF mean deviation (MD) (secondary outcome measure) between treatment groups. We hypothesize that patients treated with metformin have a slower rate of RNFL-GCIPL thinning, and a slower rate of VF MD decline compared with those treated with placebo at similar levels of IOP over the 24-month follow-up. The proposed study has the potential to mark a paradigm shift in the management of glaucoma patients by demonstrating that neuroprotection is attainable with metformin, which will alleviate the increasing burden of glaucoma blindness in China and other Asian countries where glaucoma patients with normal levels of IOP are prevalent. Furthermore, it will inform and impact the study design in future neuroprotection trials which can expedite the development of neuroprotective therapy for glaucoma.
A Clinical Trial of Acupuncture as Adjuvant Therapy for Glaucoma
GlaucomaAcupuncture1 moreThis clinical trial used acupuncture as an adjunctive treatment for glaucoma patients. It is estimated a randomized and double-blind clinical trial that 50 subjects will be enrolled and observed for 12 weeks to evaluate the clinical efficacy of acupuncture, providing a reference for future clinical treatment guidelines.
Evaluation of a Novel Head-Mounted Device for Glaucoma Testing: A Proof-of-Concept Study
GlaucomaThis proof-of-concept study aims to determine the feasibility and effectiveness of using a custom head-mounted device for visual field testing. The novel head-mounted device, with custom software, will be compared to a conventional visual field test: The Humphrey Visual Field Analyzer. The investigators will include 30 healthy normal patients, 30 glaucoma suspects, 30 patients with moderate glaucoma, and 30 patients with advanced glaucoma (total: 120 patients). Each patient will perform the conventional test and the head-mounted device visual field test during the study visit, with the order (i.e., which device the patient starts with) being randomized. After the two tests, the patient will fill out a questionnaire to gather information regarding patient comfort and satisfaction. This will repeat each week for 5 weeks, for a total of 5 study visits. The results of the tests (sensitivity thresholds) will be compared. The investigators hypothesize that the results of the conventional and head-mounted device will be similar.
Treating Psychosocial Distress in Glaucoma
GlaucomaPrimary Open Angle4 moreIn this study, using three phases, the investigators will use an iterative development approach to refine a behavioral intervention for managing concomitant psychosocial distress in glaucoma. Phase 1: The investigators will begin by developing a baseline intervention using strategies from Acceptance and Commitment Therapy (ACT), and delivered using a mobile application. Phase 2: The investigators will refine the baseline intervention for glaucoma patients using qualitative interviews conducted with primary open-angle glaucoma (POAG) patients with psychosocial distress (N=20), and health professionals (N=5). Phase 3: Finally, the investigators will measure acceptability and feasibility of the refined intervention through a single-armed pilot study (N=25). The investigators hypothesize that the refined intervention will yield an acceptable and feasible intervention in a POAG patient population, setting the stage for a future efficacy study.
Morphological Changes of Ciliary Body and Trabecular Meshwork
GlaucomaMyopiaGlaucoma is the leading cause of irreversible blindness worldwide. Although the pathogenesis remains unclear, pathologic increase in intraocular pressure (IOP) due to blocked aqueous outflow through the trabecular-Schlemm canal is known to be an important risk factor, and reduction of IOP is the only clinically validated way to retard the progression of OAG. Ciliary muscle plays a central role in the trabecular meshwork-Schlemm canal outflow pathway. Clinical evidence suggests that ciliary muscle contraction stimulated by cholinergic receptor agonist and retraction of ciliary body position after cataract surgery can dilate the lumen of Schlemm canal and reduce IOP. Currently, Ultrasound biomicroscopy (UBM) can obtain two-dimensional images of the anterior segment using high-frequency Ultrasound transducers in medical imaging studies of the ciliary body - trabecular meshwork -Schlemm canal complex. UBM has better tissue penetration than Optical coherence tomography (OCT) and can image the ciliary body better, but it has a lower resolution (30um to 50um) and is poor at imaging tiny tissues such as trabecular meshwork and Schlemm canal. The latest swept-source OCT (SS-OCT) has faster image capture rate (1000000 A scans/SEC), stronger penetration and higher resolution (8um axial resolution and 20um transverse resolution). The structure and morphology of ciliary body-trabecular meshwork-Schlemm canal complex can be clearly photographed. The investigators intend to use CASIA2 to image the ciliary body-trabecular meshwork-Schlemm canal complex before and after administration of pilocarpine in healthy individuals and patients with glaucoma to assess the effect of pilocarpine on the anatomy of the ciliary body-trabecular meshwork-Schlemm canal complex.
Impact of Home Intraocular Pressure Telemonitoring on Intraocular Pressure Control and Glaucoma...
GlaucomaIntraocular Pressure1 moreThe goal of this clinical trial is to conduct a study randomizing glaucoma patients to home intra-ocular pressure (IOP) telemonitoring combined with Smart phone-based intervention (Management Paradigm I) or Smart phone-based intervention alone (Management Paradigm II), with the objectives to compare (1) Goldmann applanation tonometry (GAT) intra-ocular pressure (IOP) measurements over the entire study period (primary outcome measure) and (2) the rates of Retinal nerve fiber layer (RNFL) thinning (secondary outcome measure) between the two Management Paradigms. We hypothesize that glaucoma patients randomized to Management Paradigm I will (1) attain lower levels of intra-ocular pressure (IOP), and (2) a slower rate of Retinal nerve fiber layer (RNFL) and ganglion cell inner plexiform layer (GCIPL) thinning compared with those randomized to Management Paradigm II because of having a more precise assessment of intra-ocular pressure (IOP) to guide intra-ocular pressure (IOP)- lowering therapy would be feasible in Management Paradigm I. It aims to: to compare (1) Goldmann applanation tonometry (GAT) intra-ocular pressure (IOP) measurements over the entire study period (primary outcome measure) and (2) the rates of Retinal Nerve Fiber Layer (RNFL) thinning (secondary outcome measure) between the two Management Paradigms. Participants will asked to do, Management Paradigm I: will be provided with an iCare Home and instructed to measure and upload 6 intra-ocular pressure (IOP) measurements weekly (2 days a week, 1 measurement in the early morning (5 am to 9 am), 1 during the mid-day (12 pm to 4 pm) and 1 in the evening (7 pm to 11pm)) to a secure server via iCare CLINIC (the number of weekly intra-ocular pressure (IOP) measurements follows the number of weekly blood pressure measurements in the HyperLink study). The morning measurement will include two readings with the first obtained in the supine position before getting out of the bed and the second obtained in the upright position right after. Patients may take additional intra-ocular pressure (IOP) measurements in supine position if they wake up in bed from sleep, as well as other times of the day, but this is not mandatory. These additional intra-ocular pressure (IOP) measurements will not be included for treatment decisions during the study period. Management paradigm II: Patients will be treated with a topical prostaglandin analogue after baseline intra-ocular pressure (IOP) measurements.
Impact of Meditation on Improving Quality of Life Among Glaucoma Patients: An Electronic Pilot Feasibility...
GlaucomaDepression3 moreGlaucoma is a chronic disease that causes loss of vision and potentially blindness as a result of optic nerve damage due to increased intraocular pressure. Currently, it is the leading cause of irreversible blindness worldwide1. In 2020, 4.1 million and 3.6 million adults over the age of 50 suffered from mild to severe visual impairment and blindness respectively induced by glaucoma1. However, these predictions are likely underestimated since glaucoma can remain asymptomatic until later stages in disease progression2. There is a convincing body of evidence suggesting that there is a linear relationship between visual impairment and decreased quality of life (QOL) among glaucoma patients3. Furthermore, evidence from The National Health and Aging Trends Study suggests that this relationship may be bidirectional where older adults with visual impairment are more likely to suffer from mental illness and older adults with mental illness are more likely to suffer from visual impairment4. Mindfulness-based meditation is a promising non-pharmacological treatment that has been shown to reduce intraocular pressure and improve QOL in patients with glaucoma5. A feasibility study will be conducted using a mixed-method design to assess the feasibility of delivering a meditation intervention online to enhance the QOL and mental health of glaucoma patients. Participants will be recruited and randomized in blocks of 10 and will undergo 1:1 randomization to the intervention arm or Health Enhancement Program (HEP) arm. The purpose of this block randomization technique is to minimize the wait time between patient recruitment and study initiation. Participants in each arm will complete online questionnaires at patient recruitment, week 1, 3, 6, and 12 to measure self-reported health, depression symptoms, anxiety, and sleep quality using REDCap, an electronic data capturing system provided by Lawson Health Research Institute (LHRI).