Active clinical trials for "Diabetic Retinopathy"

Our hypothesis is that implementing laser photocoagulation (IGTL) as an adjunctive treatment to intravitreal injections should lead to a significant reduction in the need for intravitreal injections in patients with diabetic macular edema without adverse consequences for visual acuity.

This study evaluates micro-vascular changes in patients with diabetes. Results of diseased retinas will be compared to healthy controls.

The purpose of this research is to evaluate the effectiveness of vitrectomy for the treatment of diabetic macular edema. Diabetes is known to cause retinal blood vessels to leak, leading to swelling of the central retina (macula), and decreased vision. Removing the vitreous gel with vitrectomy surgery is known to decrease the swelling caused by diabetes. Diabetic retinopathy is often treated with laser or injections of medicine in to the eye.

The goal of this research is to develop better tools for diagnosing illness of the feet and legs of people who have diabetes. Investigators will use thermal videos of the foot to aid in the refinement of a system designed to detect signs of diabetic peripheral neuropathy (DPN). The team of investigators will also look at diabetic eye disease and how it might relate to diabetic foot disease.

Diabetic retinopathy(DR) is a sight threatening condition that occurs in persons with diabetes. DR arises as a consequence of damage to the retinal blood vessels and is related to the high and fluctuating sugar levels in the blood stream. An eye with DR will have abnormal appearing retinal blood vessels which become engorged and dilated, leaky and fragile or undergo closure. The net result is a picture of haemorrhage and or ischaemia (lack of blood supply). A particular feature of DR is the accumulation of fluid in the macula which is the central part of the retina and responsible for detailed eye sight. This peculiar form of DR is called Diabetic Macular Oedema (DMO). DMO can occur in isolation without other features of DR. DMO is commoner in type 2 diabetes where insulin resistance and abnormalities of blood fats are found. The investigators wish to study DR and DMO using high resolution retinal imaging and functional tests in normal participants, those participants with diabetes without any overt signs of disease and those with DR and DMO in order to understand how the condition develops and whether there are any unique risk factors that can be identified

To date two different instruments are commercially available to measure retinal oxygen saturation and retinal vessel diameters: Dynamic Vessel Analyzer (DVA) and Oxymap. Retinal oxygen saturation analysis is based on spectroscopic evaluation of retinal fundus images. Up to now no data comparing both instruments for the measurement of retinal oxygen saturation and vessel diameter are available in the literature. Study objectives: To compare retinal oxygenation and retinal vessel diameters in healthy subjects and patients with diabetic retinopathy or retinal vein occlusion between 2 commercially available systems (DVA, Oxymap T1) Study design: Open pilot study Study population: 30 healthy volunteers, age 18-80 years 30 type 2 diabetic patients with mild or moderate non-proliferative diabetic retinopathy, age 18-80 years 30 patients with retinal vein occlusion, age 18-80 years Topically administered medication: Tropicamide (Mydriaticum "Agepha"®, Agepha, Vienna, Austria), dose: 1-2 drops per study day for dilation of the pupil Oxybuprocainhydrochloride combined with sodium fluorescein (Thilorbin®, Alcon Pharma GmbH, Freiburg, Germany), dose: 1 drop in one eye for measurements of intraocular pressure Nonylacidvanillylamide combined with Nicotinic-acid--ß-butoxyethylester (Finalgon®, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria): topical on the earlobe Methods: Dynamic vessel analyzer Oxymap T1 Blood pressure and pulse rate measurement Applanation tonometry Oxygen and carbon dioxide partial pressure measurement in arterialized blood from earlobe Main outcome variables: Difference of oxygen saturation of retinal vessels between DVA and Oxymap T1 The motive for this investigation is to compare data between 2 commercially available instruments for the measurement of retinal oxygen saturation and retinal vessel diameter in healthy subjects as well as in patients with ocular disease associated with altered retinal oxygenation. Comparative data from both systems are currently not available. Data from this study will allow the comparison of studies performed with different systems. All oxygen measurement procedures are non-invasive and painless. Hence, the risk/benefit ratio appears to be acceptable.

This study is designed to evaluate the prevalence of different stages of diabetic retinopathy and diabetic macular edema among patients suffering from type 1 diabetes (DM1) for 5 to 25 years and have been treated with intensified insulin therapy aiming near-normal blood glucose levels for the whole duration of disease. Prevalence of different stages of diabetic retinopathy and diabetic macular edema is assessed using the modified Airlie House classification and the Early Treatment Diabetic Retinopathy Study (ETDRS) retinopathy severity scheme. Results of this study will provide the basis for designing further studies as well as staging and screening guidelines for diabetic retinopathy/diabetic macular edema.

Diabetic retinopathy(DR) is one of the most common and serious microvascular complications of diabetes,which is the primary cause of vision loss of diabetic patients. The risk of blindness is 25 times that of healthy people.Fundus fluorescein angiography (FFA) is the gold standard for diagnosing the stage of diabetic retinopathy.However,FFA is an invasive examination which requires the patient to be in good physical condition and is not suitable for large-scale screening.Therefore, it is important to build up an evaluation system for early diagnosis of DR,which is more convenient, safer, and non-invasive.Firstly, this study will retrospectively analyze the FFA images of DR to find the earliest and most frequently occurring fundus quadrant.Secondly,based on the retrospective analysis results, a prospective comparative study will be conducted,which combines the fundus photography with optical coherence tomography angiography(angio-OCT) and physical indicators to find out whether it has consistency, sensitivity and specificity with FFA in diagnosing the stage of DR in order to build up a more effective,safer and faster evaluation system and clinical application for DR.

Diabetic retinopathy (DR) causes more new cases of blindness among young adults than any other disease. More than 90% of individuals with type 1 diabetes (T1D) will have some form of DR by 20 years after their diagnosis. DR is associated with long-term hyperglycemia and blood glucose variability, which induces vascular endothelial dysfunction and destruction in the retina, eventual retinal ischemia, and in the end, widespread neovascularization of the retina and optic disk. When these fragile vessels bleed, they can cause vitreous hemorrhage and loss of vision. Eventually the friable vessels fibrose and can result in retinal detachment or further retinal ischemia. Major risk factors for the development of diabetic retinopathy are time since diagnosis, age at diagnosis, and severity of hyperglycemia. Retinopathy most commonly occurs at least three years after diagnosis and most cases are diagnosed more than five years after the onset of T1D. Current guidelines from the American Diabetes Association (ADA) and American Academy of Ophthalmology (AAO) recommend that patients with T1D undergo an initial comprehensive dilated fundoscopic evaluation once the individual has had diabetes for 3-5 years and has either reached puberty or 10 years of age, whichever is earlier. These patients should receive a yearly exam thereafter, or every two years based upon the recommendation of an eye care professional. However, the prevalence of retinopathy in children is unknown and adherence to these guidelines, especially in youth, has proven difficult. Thus, it is important to make these guidelines more evidence based, as retinopathy is often asymptomatic until vision loss occurs. The first step in this process is the determination of the prevalence of retinopathy in a general population of youth with diabetes. This should be followed by determining which children are most at risk, so the guidelines can provide realistic and pertinent guidance to practitioners.

To more clearly ascertain the relationship between ocular manifestations of sickle cell disease and diabetes, specifically; whether the presence of sickle cell trait exacerbates the disease progression of diabetic retinopathy.