Active clinical trials for "Retinal Diseases"

The purpose of this study is to use optical coherence tomography angiography (OCT-A) to compare retinal vasculature after uncomplicated cataract surgery in patients with and without diabetic retinopathy.

To determine the influence of phacoemulsification on choroidal vasculature in patients with diabetic retinopathy (DR) undergoing cataract surgery

Rationale: In preparation for treatment with gene therapy, this study is being conducted in order to investigate the natural history of Inherited Retinal Dystrophies (IRDs) due to mutations in RPE65 gene. Such a study will help identify suitable patients for therapeutic intervention. Methodology: This is a multicenter retrospective, descriptive chart review study designed to assess retinal structure and function in subjects with IRDs due to mutation in RPE65 gene by visual acuity, visual field measurements, Optical Coherence Tomography (OCT), and a number of other vision-related assessments.

Diabetes mellitus is becoming a global epidemic. There is a need to devise a non invasive method for detection of diabetes and its related complication. Tear proteins are easy to collect causing no harm to a patient and different studies indicate that tear proteins of diabetic patients are significantly different from non diabetic population. This difference in the composition of tear proteins become more pronounced with advancement of diabetic retinopathy.

The primary purpose of the study is to investigate allele frequencies of candidate genes in Chinese diabetic patients with or without known diabetic retinopathy. Two hundred Chinese diabetic patients, aged between 20 - 75 years old, who have received ophthalmic fundus examination (either by an ophthalmoscope or fundus camera) within 6 months before the study will be recruited for the study. Each subject will receive anthropometric and blood pressure measurements. Then, fasting blood samples will be taken for the measurements of glucose, HbA1c, lipid profile, and biochemistry. An additional 10 ml blood sample will be taken for DNA extraction from buffy coat. Meanwhile, the participant will receive structural questionnaires for demography, personal history, medical history and concomitant medication. Single nucleotide polymorphisms (SNPs) in candidate genes and in targeted chromosome regions will be genotyped by using the ABI TaqMan assays. The differences in the distribution of genotypes and alleles between the study groups will be analyzed using appropriate statistical methods. Through the study, the investigators hope to build up a platform for future large-scale genetic studies of diabetic retinopathy. The investigators also hope to set up priority of candidate loci for future studies.

To evaluate the possibility that erythropoietin with early iron supplementation may induce retinopathy of prematurity or worsen this disease. In addition risk factors for the development of ROP will be checked.

Cord blood will be taken after birth for evaluation of cytokines level. At age of 4-6 weeks, we will do fundus examination for babies . Retrograde, we will study the perinatal risk factors in subjects found to have retinopathy. Follow up fundus will be done according to results of the first examination. By this study,we will be able later on to predict whom of preterm infants are more prone to develop retinopathy of prematurity.

Diabetic retinopathy (DR) is the leading cause of impaired visual function and blindness in adults. The fundus photographs were examined to detect DR. The DR severity was graded non-proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) according to the International Clinical Diabetic Retinopathy and Diabetic Macular Edema Disease Severity Scales. The pathogenesis of DR is complex and not fully understood, and platelet aggregation, microvascular damage, microvascular enlargement, leakage, hemorrhage, or obstruction, resulting in retinal hypoxia and retinal neovascularization. Traditional Chinese medicine (TCM) diagnostic tools are non-invasive and convenient. This study apply TCM diagnostic tools for clinical diseases, providing objective diagnostic data for evaluation to assess the association of blood stasis and DR. Furtherly we would evaluate the sensitivity and specificity of TCM diagnostic tools. This study is a prospective cross-sectional study. We enroll participants form the department of Chinese medicine, China Medical University Hospital. In total, 100 participants , composed of 50 of type 2 diabetes and 50 of diabetic retinopathy, whom previously had a retinal examination. We apply tongue diagnosis system, pulse wave analysis, body constitution questionnaires, and nailfold capillaroscopy to assess the differences of TCM diagnosis in DR. This study aims to identify the clinical symptoms of DR with TCM diagnostic tools and investigate the pattern difference and treatment for DR. Furtherly, we could design a clinical trial with improving blood circulation to treat or prevent DR, and improve the health status and quality of life in patients with type 2 diabetes.

Panretinal photocoagulation reduces the risk of visual loss by 50% in patients with diabetic retinopathy. It is recognized that laser expansion into the retina may be associated with photoreceptor loss, retinal pigment epithelial hypertrophy and visual field loss. Panretinal photocoagulation can cause alteration in retinal vascular permeability therefore, retinal thickness may be increased including retinal nerve fiber layer. On the contrary, it can damage retinal cells including ganglion cells, which may decrease the retinal nerve fiber layer thickness in the latter follow up period. Peripapillary retinal nerve fiber layer can be measured by optical coherence tomography which is a non-invasive technique for obtaining high resolution cross sectional images of a tissue.

Revadiab is case-control study aimed to demonstrate that retinal capillary density is altered in patients with type 1 diabetes with glycemic variability compared to those with comparable glycemic control without glycemic variability. An OCT angiography will be used to precisely evaluate retinal capillary density. A secondary objective will be to evaluate if glycemic variability is associated with cognitive dysfunction, using a neuro psychologic evaluation.