Evaluation of the Effect of Intravitreal Injections of Anti-VEGF on Macular Perfusion in Diabetic Patients Using OCTA (IMPACT)
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|ClinicalTrials.gov Identifier: NCT03246152|
Recruitment Status : Completed
First Posted : August 11, 2017
Last Update Posted : December 27, 2018
Anti-vascular endothelial growth factor (VEGF) drugs are the mainstay of therapy for diabetic macular edema (DME), substantially improving visual acuity for many diabetics worldwide, and proving effective for treatment of both non-proliferative and proliferative diabetic retinopathy.
Many studies such as Diabetic Retinopathy Clinical Research Network studies, RESTORE Study, and The BOLT Study have supported the use of different 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 effect of anti-VEGF drugs on macular perfusion has been inconclusive, with mixed reports of increase, decrease or no effect on perfusion in response to anti-VEGF treatment. In many of these studies, however, patients with more ischaemic retinas were not included. Retinal ischemia is an important factor in the progression and prognosis of diabetic retinopathy.
Fluorescein angiography (FA) was the method used to assess changes in macular perfusion after anti-VEGF injections in most of the studies. Despite its clinical usefulness, however, FA is known to have documented risks. Optical coherence tomography angiography (OCTA) is a new noninvasive method of acquiring high-resolution images of the retinal vasculature that can be utilized in the treatment of retinal disease without the need for dye injection. It allows the visualization of the superficial and deep retinal capillary layers separately and the construction of microvascular flow maps.
Several studies have proved the reliability of OCTA in detecting and quantifying macular ischemia in diabetics.
In this study, investigators aim to evaluate the effect of repeated intravitreal injections of different Anti-VEGF agents on the perfusion of different capillary layers in the macula of diabetic patients using OCTA.
|Condition or disease||Intervention/treatment||Phase|
|Diabetic Macular Edema Ischemic Maculopathy||Drug: Bevacizumab||Phase 4|
This is a prospective interventional study to evaluate the effect of repeated intravitreal injections of Anti-VEGF on macular perfusion in diabetic patients using optical coherence tomography angiography (OCTA).
Each patient will receive a detailed ophthalmologic examination including measurement of BCVA as well as applanation tonometry, undilated and dilated slit-lamp biomicroscopic examination and indirect fundus examination.
Duration of diabetes and its control through HbA1C measurement will be recorded for each patient.
Type 1 and 2 diabetic patients found to have BCVA worse than 6/6 and clinical evidence of macular edema will undergo SD OCT and FA.
Patients with center involved macula edema detected by SD OCT will be included in the study and will undergo baseline macular OCTA.
These patients will then undergo intravitreal injections of Anti-VEGF monthly for 3 months then OCTA will be repeated to evaluate changes in macular perfusion and SD OCT will be repeated to assess retinal thickness. Patients with center involving macular edema on SD-OCT after the first 3 injections will continue to receive intravitreal Anti-VEGF injections monthly until the edema subsides or the study duration ends. These patients then undergo a final macular OCTA for perfusion evaluation and SD OCT for thickness assessment.
OCTA will be performed with an Avanti RTVue XR system (Optovue, Inc., Fremont, CA, USA). Area of FAZ and capillary density at each capillary layer will be calculated before and after interventions using the OCTA machine software and ImageJ software.
All statistical analyses will be done using IBM SPSS v20.0 statistical software (IBM Corporation, NY, USA). Descriptive statistics will be calculated, and the data will be summarized as mean ± SD for numerical data, and as frequencies and percentages for categorical data.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||28 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Official Title:||Evaluation of the Effect of Repeated Intravitreal Injections of Anti-VEGF on Macular Perfusion in Diabetic Patients Using Optical Coherence Tomography Angiography|
|Actual Study Start Date :||October 23, 2017|
|Actual Primary Completion Date :||December 24, 2018|
|Actual Study Completion Date :||December 24, 2018|
Experimental: Bevacizumab group
Monthly intravitreal injection of 2.5 mg of Bevacizumab for at least 3 consecutive months. This is followed by treat and extend regimen after resolution of macular edema.
Repeated intravitreal injections of Bevacizumab monthly
Other Name: Avastin
- FAZ Area change [ Time Frame: 3-6 months ]Effect of repeated intravitreal Anti-VEGF injections on Foveal Avascular Zone (FAZ) area measured using the freehand tool of ImageJ
- Macular Capillary Density change [ Time Frame: 3-6 months ]Effect of repeated intravitreal Anti-VEGF injections on macular capillary density using the change in the skeletonized vascular density and fractal dimension measured by ImageJ
- Microaneurysms and Vascular changes [ Time Frame: 3-6 months ]Effect of intravitreal Anti-VEGF injections on microaneurysms and vascular changes in the superficial and deep capillary plexuses of the macula using OCTA machine software
- BCVA change [ Time Frame: 3-6 months ]Correlation of BCVA change with degree of capillary non-perfusion before and after injections
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03246152
|Cairo University Faculty of Medicine|
|Study Director:||Khaled E El Rakhawy, PhD||Cairo University|
|Study Director:||Karim A Raafat, PhD||Cairo University|
|Study Chair:||Ahmed AA Abdel Kader, PhD||Cairo University|
|Principal Investigator:||Ayman GA Elnahry, MSc||Cairo University|