Active clinical trials for "Low Tension Glaucoma"

The purpose of this study is to assess the long-term efficacy and safety of latanoprost monotherapy in patients with normal tension glaucoma (NTG) using a prospective, observational design. Visits were scheduled at 6-month intervals for 24 months. Intraocular pressure (IOP), optic nerve head findings, visual field status, and adverse events were recorded.

The purpose of this study is to evaluate whether systemic glutathione level is decreased in patients with normal tension glaucoma.

To quantify oxidative stress in circulating leukocytes of normal tension glaucoma patients, prior to and one month after routine vascular therapy.

Retinal ischemia is thought to play an important role in the pathogenesis of glaucoma. Up until today, very little is known about the metabolic alterations in the retina of glaucoma patients, since only techniques for surrogate measurements of metabolism (like blood flow velocities and vessel diameter) were available. Oximetry has provided us with an important tool to study metabolism in glaucoma, and to correlate these findings with the available blood flow evaluation techniques. Preliminary results by the group of Prof Stefánsson (2011) with the dual wavelength oximeter pointed out that deeper glaucomatous visual field defects are associated with decreased arteriovenous differences in retinal oxygen saturation. These data suggest that a change in oxygen metabolism occurs in glaucomatous retina. This reduced oxygen metabolism may be related to tissue atrophy. However, this explanation is still hypothetical, since the relation between these oximetry results and structural changes in the optic nerve have not been studied yet. What are the oximetry values in a normal population of within the same age group as the glaucoma population? To answer this question, a normative database of the investigators retinal oximetry device needs to be constructed for healthy controls. Do glaucoma patients have different retinal oximetry values than these normal patients? Are there any differences in retinal oxygenation between these glaucoma groups? To answer these questions, oximetry measurements will be performed in patients with normal tension glaucoma (NTG) and primary open angle glaucoma (POAG). Is there an association between structural optic disc and retinal nerve fibre layer changes, using Heidelberg Retinal Tomography (HRT), with alterations in retinal vascular oxygen saturation in NTG and POAG patients? Are blood flow measurements, using colour Doppler imaging (CDI), correlated with alteration in retinal vascular oxygen in NTG and POAG patients?

Color Doppler Imaging (CDI) has been providing information about ocular blood flow over the past decades. This non-invasive procedure based on ultrasound technique has identified increased resistance and decreased systolic blood velocities to exist in the ophthalmic arteries of glaucoma patients. However, existing data has provided very little information regarding the analysis of the Doppler waveform in itself and to whether variables such as early systolic acceleration or systolic/diastolic velocity ratios are of any significance in glaucoma disease. In other medical specialties using CDI technology, such as nephrology or cardiology for instance, this analysis has been part of the normal routine. This information has been used in screening patients for disturbed circulation such as arterial stenosis or providing information regarding prognosis of renal and hepatic transplants have been used for decades now. What is the normal characteristics of the waveform Doppler analysis? To answer this, the investigators will create a normative database using healthy controls. Are there signs of altered stiffness or compliance in the ophthalmic arteries of glaucoma patients? To answer this, the analysis of early acceleration acceleration and detection of an early peak systolic will be done on the Doppler curves of glaucoma patients and compared to the healthy normative database. Are there any difference between the two types of glaucoma [primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG)]? The investigators will compare the variables of the ophthalmic artery waveform in these two groups. Do any of these Doppler waveform variables have any clinical significance? To answer this, the investigators will search for the existence of any correlation between the waveform data and both functional (visual field testing) and structural (Confocal scanning laser ophthalmoscopy - CSLO) variables of the glaucoma groups.

The purpose of this study is to study the occurrence rate of masses such as brain tumors in patients with newly diagnosed Normal Tension Glaucoma.

In addition to intraocular pressure blood perfusion pressure in the optic nerve is an important factor determing the cause of glaucoma. Increasing evidence suggests that in glaucoma patients retinal blood may be decreased.

Disc hemorrhages are a known risk factor for progression of glaucoma. A positive water drinking test is also associated with progression of primary open glaucoma. The purpose of this study is to determine if patients with normal tension glaucoma and disc hemorrhages have a positive water drinking test. Patients with normal tension glaucoma and a disc hemorrhage will be recruited to undergo a water drinking test prior to any change in their treatment.

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.

Clinical features, optical coherence tomography findings and surgical outcome in eyes with macular retinoschisis and detachment with normal tension glaucoma but without optic disc pit or high myopia were evaluated.