Active clinical trials for "Glaucoma, Open-Angle"

Glaucoma is a progressive optic neuropathy that results in a loss of contrast sensitivity and visual field if not detected and treated. When glaucoma patients undergo cataract surgery, they are often not ideal candidates for many existing presbyopia correcting IOLs as they reduce contrast sensitivity because of the splitting of light and are more likely to have visual disturbances secondary to diffractive steps in the IOL design. This is largely because of a higher rate of ocular surface disease and meibomian gland dysfunction in this patient population due to the chronic utilization of topical drops. As a result of this, patients with glaucoma currently receive aspheric monofocal IOLs during cataract surgery, which are lenses with minimal loss of contrast sensitivity but only one point of focus (typically targeted for distance). This necessitates the use of glasses for near and intermediate vision and has an impact on quality of life for these patients. The Vivity Extended Depth of Focus (EDOF) IOL is a new technology that maintains uncompromised distance vision and provides improved intermediate vision correction, reducing the need for glasses. This lens uses a new optical system with no diffractive steps in the IOL; trials in non-glaucomatous patients have shown the rate of visual aberrations to be comparable to an aspheric monofocal IOL which are currently the standard of care in patients with glaucoma. There is no published data on outcomes of this IOL in patients with primary open angle glaucoma (POAG) or ocular hypertension (OHT). Studies are required to evaluate the clinical success of this new lens technology in glaucomatous patients. This will be the first study in Canada to report clinical outcomes of the Vivity IOL in this patient cohort.

Structural and functional brain changes of primary open-angle glaucoma patient will be examined with fMRI. POAG patients and control group were examined with 3.0T magnetic resonance imaging. The gray matter, white matter and cerebrospinal fluid volume images will be obtained and analysed.

Glaucomatous damage not only occurred to retinal ganglion cells in the eyes, but went across optic nerves, visual chiasm, lateral geniculate nucleus (LGN) and finally the visual cortex; the neural degenerations could be identified through the whole visual tract, which suggests the central nerve system may play a vital role in the progression of glaucoma. The investigators used MRI to investigate changes of visual pathway in vivo.

since glaucoma is considered an optic neuropathy, new treatments for glaucoma are being continuously investigated, including neuroprotection. Previous studies implied that phenytoin, a potent anti-convulsive drug, has a neuroprotective role, and Na+ channels blockage was suggested as a possible mechanism. This study predicts that glaucoma patients taking Phenytoin will have a less advanced glaucoma as compared to patients not taking the drug. Glaucoma severity will be determined by visual acuity, visual fields, optic disc cupping and nerve fiber layer thickness

Characterization of posterior corneal changes in primary open angle glaucoma patients, using Scheimpflug examination.

Metabolomics consists in the study of metabolites in body fluids or tissues. It investigates the consequences of the activity of genes and proteins. One of its advantages is that it is able to do a simultaneous measurement of metabolic changes in living organisms as a response to a disturbance (disease, diet, environment, others) and because a metabolic profile is summative of all the biochemical processes occurring in the body at a given time, it makes no presumption about the relative importance of these processes. Ultimately it is a fingerprint of the organism's health status, at a given time. Metabolomic analysis of serum, plasma and urine has revealed panels of metabolites that distinguish patients with cardiovascular disease, breast cancer, Parkinson disease, Alzheimer's disease and diabetes from control patients. Regarding ocular diseases only few studies have been published, related to diabetic retinopathy, retinal detachment, age-related macular degeneration, uveitis and glaucoma. Glaucoma is one of the leading causes of blindness in the world, according to the World Health Organization, and there are still no biomarkers that can provide an early diagnosis. Nowadays, glaucoma classification relies substantially in the measurement of intraocular pressure (IOP), which can be rather artificial and also unreliable since IOP values can fluctuate during the day. Moreover, patients with normal IOP values can also develop glaucomatous neuropathy (normal-tension glaucoma, NTG) and progress even when IOP is decreased. Several studies have shown that NTG patients suffer from a systemic vascular dysregulation, with higher rates of systemic hypotension, Raynaud phenomenon and migraine. Hence, other mechanisms than an increased IOP are of importance in the development and progression of glaucoma. Only one metabolome-wide study has been made in glaucoma (Burgess, I.; 2015). In a sample of 72 american patients with primary open angle glaucoma (POAG), the authors found significant differences in comparison to controls. The hypothesis for this study is that glaucoma patients will differ from controls, and POAG patients will differ from NTG patients. The investigators will look into metabolomics as a way to create a method to diagnose and stratify patients, as an add-on or alternative to the currently available diagnostic tools like IOP, functional and structural measurement.

The purpose of this study is to investigate how much selective trabeculoplasty (SLT) influences intraocular pressure (IOP) fluctuations measured with iCare Home rebound tonometry (RTHome) in patients with primary open-angle glaucoma (POAG) or pseudo-exfoliation glaucoma (PEX).

According to the National Eye Institute, Glaucoma affects about three million Americans. Among Blacks in the United States, open- angle glaucoma is the leading cause of irreversible visual loss. Glaucoma is four times more likely to develop in Blacks than in Whites. This is a prospective longitudinal, multi- site observational cohort study designed to obtain visual function and optic nerve structure data on eyes of Black and White Americans. The investigators will evaluate the relationship between changes in the structure of the eye and the vision loss caused by glaucoma.This is the first study where both populations are matched for quality of care and equal access to care.

The primary aim of the Erlangen´s Glaucoma Contrast Sensitivity-Study (EGCS-Study) is the evaluation of the diagnostic and prognostic validity of a diagnostic procedure, measuring contrast sensitivity. No therapeutic studies are performed.

The purpose of this study is to compare the two psychophysical perimetric techniques regarding progression of the visual field.