Effect of Benzalkonium Chloride Preserved and Preservative-free Latanoprost Eye Drops on Conjunctival...
GlaucomaOcular Hypertensiona randomized, investigator-blind, interventinal study will compare the effect of benzalkonium-chloride (BAK) preserved and preservative-free (PF) eye drops on conjunctival goblet cells.
Aqueous Humor Dynamic Components That Determine Intraocular Pressure Variance
GlaucomaOHT - Ocular HypertensionGlaucoma is a major cause of blindness. The inability to predict a patient's IOP response to medications is a critical barrier for the clinician to consistently provide highly effective IOP-based treatments. Current trial-and-error approaches to glaucoma management are inefficient and have not addressed this barrier as there are no predictive factors for drug response. Our long-term goal is to improve outcomes by identifying biomarkers and environmental factors that profile a patient at risk for glaucoma by age-of-onset, rate of disease progression, "poor response" to treatment, and large IOP fluctuation. Our purpose of this research project is to address this critical barrier by focusing on physiological factors that predict IOP response to drugs.
Travoprost Intraocular Implant in Conjunction With Cataract Surgery
Open Angle GlaucomaOcular HypertensionSubjects with cataract requiring extraction and who have open-angle glaucoma or ocular hypertension will undergo screening and washout from IOP-lowering medication, if applicable. Eligible subjects who meet all inclusion criteria and none of the exclusion criteria and who undergo successful cataract extraction with implantation of a posterior chamber intraocular lens (PC-IOL) will receive a travoprost intraocular implant and followed up for 12 months.
Automated Applanation Tonometry
GlaucomaGlaucoma1 moreGoldmann Applanation Tonometry (GAT) is considered the clinical gold standard for eye pressure measurements and yet it is known to be a subjective measurement with limited repeatability and limited portability. The purpose of this study is to develop an automated and objective method for performing applanation tonometry using standard ophthalmic equipment as well as using 2 portable prototypes.
Effect of Lowering IOP in Glaucoma Suspects With HM
GlaucomaSuspect1 moreCurrently, whether and when intraocular pressure (IOP) lowering medication should be used in glaucoma suspects with high myopia (HM) is still a dilemma. Randomized trials are required to evaluate whether IOP lowering influences the incidence of glaucoma suspect progression in HM eyes.
Long-term Safety and Efficacy Extension Trial of Bimatoprost SR
Open-Angle GlaucomaOcular HypertensionThis study will evaluate the long-term safety and efficacy of Bimatoprost Sustained Release (SR) in patients with open-angle glaucoma or ocular hypertension who completed 1 of the 4 Phase 3 Bimatoprost SR studies (192024-091, -092, -093, or -095) and received Bimatoprost SR or who received commercial DURYSTA (Bimatoprost SR) in the open-label Phase 4 ARGOS study (MED-MA-EYE-0648) and completed (or exited early from) the study.
Effect of IOP Lowering on Progressive HM
High MyopiaGlaucoma1 moreCurrently, whether and when intraocular pressure (IOP) lowering medication should be used in progressive high myopia (HM) to control axial elongation is still a dilemma. Randomized trials are required to evaluate whether IOP lowering influences the growth of axial length in progressive HM eyes.
A More Engaging Visual Field Test to Increase Use and Reliability in Pediatrics
GlaucomaSuspect4 moreThe majority of young children do not think that visual field (VF) testing of peripheral vision is similar to a game; therefore, it is not surprising that they have difficulty maintaining attention during VF testing and thus the test reliability suffers as a consequence. Poor VF reliability has been a longstanding, major issue since it leads to an increased number of tests and/or longer duration of time needed to determine when there are true vision losses. Providers are less likely to obtain VF tests in children since the results are of doubtful value and challenging to interpret when they are inconsistent. Effectively this means that children with untreated, slowly progressive eye diseases may go undiagnosed and incur greater visual losses. The investigators aim to create a prototype device that the investigators hypothesize will make VF testing more engaging for young children, thus increasing their attention and consistency of their responses to the test stimuli, which in turn should improve VF reliability. The components include a microdisplay video screen (1.5" diameter) as the fixation target (instead of the standard LED light) displaying video clips of popular cartoon characters, and audio clips of impersonated cartoon character voices presented by the test operator to provide instructional feedback based on the child's performance during testing. Improved VF reliability from the investigators intervention would translate to improved diagnosis and care for young childrens' peripheral vision loss through widespread implementation of the investigators innovative, affordable and readily adoptable system at eye care providers' offices.
Optimal Treatment Protocol for Selective Laser Trabeculoplasty - Repeat Trial
GlaucomaOpen-Angle2 moreGlaucoma is a common eye disease that can lead to blindness. The only known way to reduce the rate of disease progression is by reducing the pressure in the eye (the intraocular pressure, IOP). Selective laser trabeculoplasty (SLT) is an ophthalmic laser intervention with the purpose of reducing the IOP. SLT can be performed in different ways, with four of the treatment protocols being evaluated in the Optimal SLT (OSLT) trial. SLT is a repeatable procedure, but scientific evidence is scarce regarding more than one repetition. In this trial, patients included in the OSLT trial will be invited to the extended trial (OSLT-R), for further follow-up and re-treatment with SLT, if needed.
Investigation of Neurovascular Coupling in Glaucoma Patients and Healthy Subjects
GlaucomaOpen-Angle2 moreGlaucoma is characterized by a progressive loss of retinal ganglion cells (RGCs) leading to optic nerve head (ONH) damage and associated visual field defects. The main risk factor for glaucoma is elevated intraocular pressure (IOP). Reducing IOP slows down the progression of the disease as several large multicenter trials have shown. Some patients, however, still progress despite adequately controlled IOP. As such, there is considerable interest in approaches that rescue RGCs independent of IOP, a strategy called neuroprotection. Although this field was actively discovered in the last 20 years in the brain and the eye, no non-IOP related treatment is clinically available to date. Various approaches are currently studied in some detail. One interesting strategy focuses on the neurovascular unit. The blood flow of the human retina is controlled by complex mechanisms that include myogenic, metabolic and hormonal factors. The high consumption of oxygen in the human retina is crucial for normal functioning of the organ. As in the brain, blood flow in the retina is also controlled by neurovascular coupling. This means that the retina increases its blood flow to regions in which neurons are activated. This is done in an effort to provide more oxygen and glucose to the active neurons. In the recent years evidence has accumulated that astrocytes play a key role in mediating this vasodilator signal. In the brain, abnormalities in neurovascular coupling have been observed in diseases like stroke, hypertension, spinal-cord injury and Alzheimer's disease. This break-down of neurovascular coupling is considered to play a key role in neuronal death in these diseases. In the retina, abnormalities in neurovascular coupling have been observed in diseases as diabetes and glaucoma. Most of the data obtained in the human retina stem from a system that measures retinal vasodilatation during stimulation with flickering light. The investigators have previously shown that flicker stimulation of the retina is, however, also associated with a pronounced increase in retinal blood velocities. In this study the investigators employed laser Doppler velocimetry (LDV) for the measurement of retinal blood velocities, but this technique is not clinically applicable because it requires excellent fixation of the subject under study. In the present study, the investigators propose to use an alternative system for neurovascular coupling that they have developed recently. In this approach, the investigators use bi-directional Fourier-domain optical coherence tomography for the assessment of retinal blood flow. Optical coherence tomography (OCT) is a non-invasive optical imaging modality enabling cross-sectional tomographic in vivo visualization of internal microstructure in biological systems. In ophthalmology, OCT has become a standard tool in visualizing the retina and nowadays is considered also as a standard tool in the diagnosis of retinal disease. In the recent years, conventional time domain OCT was replaced by Fourier domain OCT providing significantly improved signal quality. This bidirectional system overcomes the limitations of previously realized techniques, which include doubtful validity and limited reproducibility. In addition, pattern ERG, multifocal ERG and oscillatory potentials will be measured to allow for concomitant assessment of neural function. The investigators seek to measure neurovascular coupling in the human retina in patients with early primary open angle glaucoma (POAG), normal tension glaucoma, ocular hypertension and a healthy control group. In order to obtain information on neurovascular coupling, both neuronal function as well as retinal blood flow need to be measured. In the present study, the investigators will employ pattern ERG, multifocal ERG as well as oscillatory potentials to assess the function of the inner retina. Retinal blood flow through major retinal arterial and venous branch vessels will be measured before, during and after flicker stimulation with the dual-beam bidirectional Fourier Domain Doppler OCT coupled to the commercially available Dynamic Vessel Analyzer (DVA) produced by IMEDOS, Jena, Germany, which provides adequate resolution to study the retinal circulation.