Comparison of the Effect of Ranibizumab Versus Bevacizumab on the Macular Perfusion in Diabetic Macular Edema Using OCTA
The Early Treatment Diabetic Retinopathy Study (ETDRS) group founded guidelines for treating patients with clinically significant diabetic macular edema (DME) with focal/grid macular laser photocoagulation. Since then, macular laser, and steroids, were the main therapies for the treatment of DME until anti-vascular endothelial growth factors (anti-VEGF) drugs were developed after a growing body of scientific evidence implicated VEGF in the pathophysiologic process of DME. Anti-VEGF drugs have been implicated in the treatment of DME. VEGF has been shown to play an important role in the occurrence of increased vascular permeability in DME. VEGF levels are significantly higher in patients with DME and extensive leakage than in patients with minimal leakage. Many studies such as Diabetic Retinopathy Clinical Research [DRCR] Network studies, RESTORE Study, RISE and RIDE Research Group, and The BOLT Study have supported the use of anti-VEGF agents in the treatment of DME with better visual outcomes using anti-VEGF injections alone or in combination with other treatments. Several ocular complications of intravitreal anti-VEGF injections have been reported including endophthalmitis, cataract, and retinal detachment. The different effects on macular perfusion between different anti-VEGFs have yet to be fully concluded with mixed conclusions that it increases or decreases or has no effect on perfusion of the macula in response to Anti-VEGF treatment. In many of these studies, however, patients with more ischemic retinas were not included. Retinal ischemia is a vital factor determining the diabetic retinopathy progression and prognosis. Optical coherence tomography angiography (OCTA) detects blood flow by analyzing signal decorrelation between two sequential OCT cross-sectional scans at the same location. As it detects the movements of red blood corpuscles within the vessels, compared to the stationary retinal surroundings, which will result in signal disparity and imaging The split-spectrum amplitude-decorrelation angiography (SSADA) algorithm improves the signal to noise ratio. OCTA is considered a reliable tool in the detection and quantification of macular ischemia in diabetics. In this study, the investigators aim to compare the effect of repeated intravitreal injections of ranibizumab and bevacizumab on the perfusion of different capillary layers in the macula of diabetic patients using OCTA.
A First in Human Trial to Study Safety and Tolerability of Single Rising Intravitreal Doses (oPen Label, Non-randomized, Uncontrolled) and in Addition the Early Biological Response of mulTiple Intravitreal Doses (Double-masked, RandomIzed, Sham-controlleD) of BI 765128 in Panretinal photocoaGulation (PRP) Treated Diabetic rEtinopathy (DR) Patients With Diabetic Macular Ischemia (DMI) - the PARTRIDGE Study
This study is open to adults with diabetic macular ischemia who have received laser treatment. The main purpose of this study is to find out whether people with diabetic macular ischemia can tolerate a medicine called BI 765128. In this study, BI 765128 is given to people for the first time. The study has 2 parts. Part A tests 3 doses of BI 765128. Participants get either a low, medium or high dose of BI 765128 as a single injection into the eye. If participants tolerate it well, the highest dose will be used in part B. In part B, participants are put into 2 groups randomly, which means by chance. 1 group gets BI 765128 as injection into the eye. The other group gets sham injections. A sham injection means that it is not a real injection and contains no medicine. Participants cannot tell whether they get the real injection or a sham injection. In this part, participants receive study treatment once every month for 3 months. Participants in part A are in the study for about 4 months and visit the study site about 8 times. Participants in part B are in the study for about 5 months and visit the study site about 7 times. The doctors regularly check participants' health and take note of any unwanted effects.
Correlation Between Macular Ischemia and Peripheral Ischemia in Patients With Diabetes
The contribution of OCT- angiography (OCT-A) allows to consider, in a more or less long term, a drastic reduction in the use of fluorescein angiographies in diabetic retinopathy. The accuracy of the analysis of the vascularization of retinal layers of the posterior pole of the eye by the OCT-A , will detect, early and in a quantifiable manner, whether or not there are areas of macular ischemia in a patient. However, current technical limitations (small field analysis) of OCT-A imaging only allow a limited study of retina at the posterior pole of the fundus. This study seeks to demonstrate whether there is a link between macular ischemia detected by the OCT-A and peripheral retinal ischemia detected by the fluorescein angiographies, in diabetic patients.