View clinical trials related to Glaucoma.
Filter by:The purpose of the study is to repeatability, reproducibility and agreement of eye measurements in retina and glaucoma patients.
Ocular blood flow has been consistently demonstrated to be altered in glaucoma patients when compared to otherwise healthy individuals. Numerous Doppler studies have shown a decrease in flow velocities in the retrobulbar arteries in what appears to be related to the degree of the glaucomatous disease. The anatomic pathway of the several arteries into the eye is intricately complicate, with at least one of them (the central retina artery) penetrating the optic nerve before entering the eye and supplying the innermost structures of the globe. As the optic nerve is surrounded by a layer of cerebrospinal fluid (CSF) which is in continuity with the rest of the central nervous system, this central retinal artery has also to cross this CSF containing compartment. Because of the intrinsic pressure this CSF - corresponding to the intracranial pressure at the orbital level - the possibility exists that this pressure around the optic disc could affect the blood flow of the arteries that go through it. The investigators will try to detect if a correlation exists between the optic nerve sheath diameter and the blood flow in the retrobulbar vessels of glaucoma patients.
Importance: Visual field loss after retinal damage in glaucoma is considered irreversible and methods are needed to achieve vision restoration. Behavioral vision restoration training (VRT), shown to improve visual fields in hemianopia and optic nerve damage, might comprise such a method. Objective: To determine if behaviorally activating areas of residual visual (ARV) using VRT by daily one hour training for 3 months improves detection performance in perimetry compared to a vision discrimination task in the intact visual field sector.
A spontaneous venous pulsation over the optic disc is an ophthalmological sign that can potentially be found in up to 98% of healthy individuals. In fact, the lack of this spontaneous retinal venous pulse has been consistently implicated as an indicator of a more advanced form of certain ocular diseases, specifically open-angle glaucoma. However, the mechanisms behind these change in the retinal venous system are not clear. Some evidence suggests that extraocular features such as intracranial pressure (ICP) may play a role in regulating the intraocular venous outflow. The reasons for this hypothetical downstream resistance to venous outflow are not fully understood, with advances in this field being limited by our technological-imposed difficulties in assessing the structures behind the globe. However, it has been established that the volume of cerebrospinal fluid surrounding the optic nerve correlates with the ICP at the orbital level. Recent studies have suggested that non-invasive ultrasound-based recordings have correlated this surrogate for orbital ICP with the intraocular pressure (IOP) in glaucoma patients with an otherwise normal IOP range (normal tension glaucoma - NTG). The investigators will therefore conduct a test to determine if this cerebrospinal volume surrounding the optic nerve correlates with the frequency of observation of an otherwise signal of venous dysfunction (i.e. the lack of a visible pulse in the retinal central vein) Additionally, the investigators will assess if this correlation is different between healthy individuals, hypertensive primary-open angle glaucoma or NTG patients.
Retinal ischemia is thought to play an important role in the pathogenesis of glaucoma. Recent findings have confirmed that there is a direct correlation between the levels of venous oxygen saturation and the degree of the glaucomatous disease, presumably due to a decrease in retinal cell metabolism. However, glaucoma patients have been suggested to have a different pattern in retinal venous circulation. For instance, the observation of a visible pulsating central retinal vein is a phenomenon that can be seen in up to 98% of the healthy individuals but is identifiable in less than 50% of glaucoma patients. While the nature of these venous changes are not year clear, the lack of a visible pulsating flow could suggest an increased intraluminal venous pressure due to some obstruction from both ocular or extraocular structures. This undetermined increase in venous pulse pressure could then significantly decrease perfusion pressures and therefore further decrease oxygen supply to the retinal tissues. The investigators will therefore try to determine if there is a significant difference between the oxygen saturation of the retinal vessels in both glaucoma patients with and without a visible pulsating central vein
The aim of the study is to evaluate the effectiveness and the safety of the cyclocoagulation using HIFU in glaucoma patients
This study will investigate if micropulse laser trabeculoplasty (532nm) is as effecttive as or better than the conventional laser trabeculoplasty (532nm), it might be a new treatment strategy for glaucoma patients. It is done with a laser device that can also be used for many other ophthalmic applications, thus reducing the economic burden of treatment.
This study will assess angle width in Chinese patients with Open-angle Glaucoma and/or Ocular Hypertension.
The purpose of this research study is to determine the diurnal and nocturnal effects of Travoprost with SofZia (Travatan Z) on intraocular pressure and ocular perfusion pressure.
The primary objective of this crossover trial is to compare the 3-month, mean 24-hour intraocular pressure (IOP) control and safety obtained with two popular fixed combinations in glaucoma patients insufficiently controlled with latanoprost monotherapy. This study will compare the 24-hour efficacy of travoprost/timolol fixed combination without benzalkonium chloride given once in the evening, versus the latanoprost/timolol fixed combination given in the evening. It is assumed that travoprost/timolol fixed combination will provide better quality of 24-hour pressure control.