Caffeine Consumption in Glaucoma Patients and Healthy Subjects
GlaucomaPrimary Open AngleCaffeine is the most widely consumed drinking nutrient in the world. Caffeine effects various organs and the vascular system. It decreases ocular blood flow due to vasoconstriction.
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.
Screening and Intervention for Glaucoma and Eye Health Through Telemedicine
GlaucomaThis is a multiple site, randomized study that will assess the effects of personalized eHealth education and motivational-interviewing-based counseling on patient adherence to physician follow-up appointments.
Effectiveness of NIBS and Perceptual Learning for Improving Visual Performance in Patients With...
GlaucomaGlaucoma is a complex disease that can result in progressive vision loss. It is the second leading cause of blindness, accounting for 23% of permanent blindness in Hong Kong. There are no treatments that restore vision lost to glaucoma. However, recent studies have shown that vision can be improved by non-invasive brain stimulation (NIBS) and visual training. This study will examine the effect of perceptual learning and NIBS on improving quality of life, visual function and functional performance in patients with peripheral field loss due to glaucoma.
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.
Malay Glaucoma Eye Study II Navigation, Mobility and Reading Ability in Primary Glaucoma
Primary Open Angle GlaucomaPrimary Angle Closure GlaucomaWith the improvement of health system, the life span of Asians has increased tremendously especially in Malaysia. As an early preparation to be an 'aging country' in 2023, Malaysia needs to prepare infrastructure and policy to improve quality of life (QoL) in older adults. Glaucoma is an aging related chronic disease that cause progressive optic neuropathy and visual field defect1. The main aim of glaucoma treatment is to slow down disease progression and preserve patient's QoL2. Modification of intraocular (IOP) is believed to be the mainstay of treatment but may not prevent progression of the disease. Modification of lifestyle has been found to change the prognosis of many chronic diseases such as diabetes mellitus. However, there is minimal evidence on the effect of lifestyle modification on glaucoma. Although constricted visual field almost asymptomatic especially in primary open angle glaucoma but many domestic injuries such as fall has been reported. Glaucoma patients reported greatest restriction with mobility especially driving compared to the other domains3,4. Reduction of walking and moderate-to-vigorous physical activity was also found in those with bilateral visual field loss5. Progressive constriction of visual field has been found to increase dependency, reduce mobility, pleasure of reading and QoL of glaucoma patients6. This will lead to psychological and emotional disturbance, in certain cases even resulted in depression. On the other hand, being physically active is found to have some protective effect against development and severity of glaucoma8,9. Thus, identifying problems related to physical activities in constricted visual field is important for improvement of rehabilitation and exercise regime for glaucoma patients. An exercise regime must be effective without causing major changes to IOP, safe in patients with constricted visual field and sensitive to social culture of Malaysians. Addressing these issues will lessen dependency and promotes healthy living among older adults. Improvement in navigation perhaps may increase the physical activities in glaucoma. Reading is another important pleasure in life. Visual field defect in glaucoma patients has been reported to associate with slower reading speed, saccade rate and visual span10,11. Identification of factors associated with difficulty in reading among glaucoma patients and development of rehabilitation regime in reading may improve the happiness index in literate patients. Nevertheless, there is no specific rehabilitation program to improve reading abilities among glaucoma patients. A combination of visual rehabilitation of low vision therapy and occupational therapy is ideal. Although, there is improvement in reading ability and mobility post low visual aid rehabilitation but there is no evidence on glaucoma patients specifically12. Improvement in daily living and dependency may improve their QoL. Happiness perhaps may improve the balance between oxidative stress damage and antioxidant level. Many previous studies discovered that various biomarkers of oxidative stress are elevated in people with depression, and anxiety disorders13. Similarly, oxidative stress has been implicated in pathogenesis of glaucoma and accelerates retinal ganglion cell damage in glaucoma14. Indirectly, improvement of QoL will help in halting the progression of visual field defect. Based on the previous research project on Malays in Malaysia, navigation and mobility has been identified to be mostly affect in primary glaucoma patients based on QoL questionnaires. Physical activities have potential protective effect against progression and severity of glaucoma9. Improvement in navigation, physical activities and reading ability, perhaps may improve their QoL. The main problem is how do we improve their navigation, physical activities and reading ability despite their constricted visual field. The most important step is to understand the problem and issues pertaining to the navigation, physical activities and reading faced by patients with glaucoma.
An Interventional, Confirmative, Post Marketing Clinical Followup (PMCF) Study to Evaluate Performance...
Opthalomology/Dry EyeStudy Rationale: The glaucomas are a group of optic neuropathies characterized by progressive degeneration of retinal ganglion cells. These are central nervous system neurons that have their cell bodies in the inner retina and axons in the optic nerve. Degeneration of these nerves results in cupping, a characteristic appearance of the optic disc and visual loss. The biological basis of glaucoma is poorly understood and the factors contributing to its progression have not been fully characterized. Glaucoma affects more than 70 million people worldwide with approximately 10% being bilaterally blind, making it the leading cause of irreversible blindness in the world. Glaucoma can remain asymptomatic until it is severe, resulting in a high likelihood that the number of affected individuals is much higher than the number known to have it. The tear film is fundamental in the maintenance of the ocular surface. Any condition that adversely affects the stability and function of the tear film such as dry eye symptom, blepharitis, and meibomian gland dysfunction, dysfunctional tear film syndrome, or toxicity of topical medications may result in onset of an ocular surface disease (OSD). The symptoms of OSD may include dryness, burning or stinging, itching, irritation, tearing, photophobia, foreign-body sensation, grittiness, redness, fatigue, fluctuating visual acuity, and blurred vision. OSD is a common comorbidity in glaucoma patients in part due to the fact thatits prevalence as in glaucoma increases with age. OSD is seen in approximately 15% of the general elderly population and is reported in 48% to 59% of patients with medically treated glaucoma. One in six patients with glaucoma has OSD symptoms severe enough that they need some form of treatment. Ophthalmic solutions with soothing and refreshing proprieties, as addon treatment to glaucoma therapy, could relieve the OSD symptomatology, dry eye like, in glaucoma patients, improving their quality of life. For these reasons, an interventional, confirmative, post marketing clinical followup (PMCF) study was planned to evaluate the performance and safety of ophthalmic solutions used to relieve dry eyes like symptoms in glaucoma patients. Study Objective: The objectives of this PMCF study are confirmation of the performance, collection of additional safety data regarding expected adverse events and detection of potential unexpected adverse events associated with use of three investigational products (IPs). The IPs are on the market with the following brand names: Afomill Refreshing Soothing Afomill Anti-redness Eye Drops Iridil
Nanodropper Use in Primary Open-Angle Glaucoma Patients: A Non-Inferiority Trial
Ocular HypertensionPrimary Open Angle GlaucomaThis randomized, single-masked, crossover, non-inferiority trial aims to evaluate the safety and efficacy of Nanodropper-mediated microdrops of ocular hypotensive topical treatments (experimental intervention) compared to standard drops of the same medication(s) (active comparator) in Wilford Hall Ambulatory Surgical Center (WHASC) primary open-angle glaucoma (POAG) and ocular hypertension (OHTN) patients.
24-hour Efficacy and Tolerability of the Tafluprost-timolol Fixed Association Without Preservatives...
GlaucomaOpen-Angle1 moreThis is a phase IV, interventional, multi-center, open clinical Trial. Patients will be administered one eye drop of tafluprost/timolol fixed combination at 20:00 (+/- 1 hour), in the treatment of open angle glaucoma and ocular hypertension. The patients will suspend the treatment with latanoprost.
Analysis of Conjunctival Changes as Indicators for Ab-interno Gelatin Microstent Implantation Surgery...
GlaucomaGlaucoma Open-Angle PrimaryTrabeculectomy and XEN45 gel stent implantation are glaucoma surgeries that creates an aqueous humor (AH) shunt towards the subconjunctival space (filtration bleb). Once the AH reaches the subconjunctival space, it is removed by different paths such as the trans-bleb wall route. For this reason, the conjunctiva is considered an essential structure that may condition the glaucoma filtering procedures outcomes. As part of the inflammatory response, an unbalanced fibrosis during the postoperative period may lead to a bleb cavity scarring and failure; for this reason, bleb massage and antifibrotic injections (i.e., 5-Fluoruracil) are frequently required as part of the postoperative care of these procedures. There have been described several risk factors, such as intraocular pressure (IOP) lowering medications, previous surgical interventions or ocular surface disease that may predispose to an early failure. These preoperative factors fail to aim to predict the surgical outcomes. However, ocular biomarkers may overcome this limitation. There are promising studies that have analyzed the role of in vivo confocal microscopy (IVCM), anterior-segment optical coherence tomography (AS-OCT) and conjunctival cytology impression as clinical tools that may improve the filtration bleb assessment at a cellular level.