Active clinical trials for "Diabetic Retinopathy"

Diabetic macular edema (DME) is an important cause of central vision impairment among people with diabetic retinopathy (DR), which can have a significant adverse effect on daily activities and quality of life. Diabetic patients with preexisting DME are at increased risk of worsening edema following cataract surgery. Previous studies also reported progression of DR after cataract surgery. Clinically significant DME is now classified into center-involved DME (CI-DME) and non center-involved DME (non-CI DME). Randomized clinical trials have established intravitreal antivascular endothelial growth factor (VEGF) therapy as first-line treatment for visual impairment from CI-DME and studies have addressed the influence of anti-VEGF therapy among patients with DME undergoing cataract surgery. However, for patients with non-CI DME before cataract surgery, whether anti-VEGF therapy is necessary at the end of surgery to prevent CI-DME is still clinically controversial. In order to evaluate the prophylactic effect of Conbercept (a recombinant fusion protein with high affinity to all VEGF isoforms and PIGF) intravitreal injection at the conclusion of cataract surgery for DME in patients with DR, the investigators will prospectively recruit 40 cataract patients with DR and non-CI DME and randomly assign these subjects into the study group (combined cataract surgery and intravitreal Conbercept injection, 20 cases) and the control group (cataract surgery alone, 20 cases). The primary outcomes include mean changes in central retinal thickness (CRT) and in diabetic retinopathy severity score (DRSS). The secondary outcomes include changes in best corrected visual acuity (BCVA), foveal avascular zone (FAZ), retinal vessel density (VD), the aqueous concentrations of VEGF, PIGF, interleukin- (IL-) 2, IL-5, IL-6, and IL-8.

Blindness can be caused by many ocular diseases, such as diabetic retinopathy, retinal vein occlusion, age-related macular degeneration, pathologic myopia and glaucoma. Without timely diagnosis and adequate medical intervention, the visual impairment can become a great burden on individuals as well as the society. It is estimated that China has 110 million patients under the attack of diabetes, 180 million patients with hypertension, 120 million patients suffering from high myopia and 200 million people over 60 years old, which suggest a huge population at the risk of blindness. Despite of this crisis in public health, our society has no more than 3,000 ophthalmologists majoring in fundus oculi disease currently. As most of them assembling in metropolitan cities, health system in this field is frail in primary hospitals. Owing to this unreasonable distribution of medical resources, providing medical service to hundreds of millions of potential patients threatened with blindness is almost impossible. To solve this problem, this software (MCS) was developed as a computer-aided diagnosis to help junior ophthalmologists to detect 13 major retina diseases from color fundus photographs. This study has been designed to validate the safety and efficiency of this device.

Diabetic macular edema (DME) is one of the leading causes of visual impairment in patients with diabetes. Fluorescein angiography (FA) plays an important role in diabetic retinopathy (DR) staging and evaluation of retinal vasculature. However, FA is an invasive technique and does not permit the precise visualization of the retinal vasculature. Optical coherence tomography (OCT) is a non-invasive technique that has become popular in diagnosing and monitoring DR and its laser, medical, and surgical treatment. It provides a quantitative assessment of retinal thickness and location of edema in the macula. Automated OCT retinal thickness maps are routinely used in monitoring DME and its response to treatment. However, standard OCT provides only structural information and therefore does not delineate blood flow within the retinal vasculature. By combining the physiological information in FA with the structural information in the OCT, zones of leakage can be correlated to structural changes in the retina for better evaluation and monitoring of the response of DME to different treatment modalities. The occasional unavailability of either imaging modality may impair decision-making during the follow-up of patients with DME. The problem of medical data generation particularly images has been of great interest, and as such, it has been deeply studied in recent years especially with the advent of deep convolutional neural networks(DCNN), which are progressively becoming the standard approach in most machine learning tasks such as pattern recognition and image classification. Generative adversarial networks (GANs) are neural network models in which a generation and a discrimination networks are trained simultaneously. Integrated network performance effectively generates new plausible image samples. The aim of this work is to assess the efficacy of a GAN implementing pix2pix image translation for original FA to synthetic OCT color-coded macular thickness map image translation and the reverse (from original OCT color-coded macular thickness map to synthetic FA image translation).

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.

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.

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.

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

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.

Fractalkine (FKN) is a chemoattractant and adhesion molecule for leukocytes. Angiogenic effect of FKN also has been reported. We investigate FKN-mediated angiogenesis in ocular angiogenic disorders.