Alone laser versus bevacizumab plus laser for diffuse diabetic macular edema (ALBA randomized trial)

Purpose: To report the 12-month results of laser (treatment G1) versus intravitreal bevacizumab combined with laser (treatment G2) in patients with diffuse diabetic macular edema (DME). Methods: In this single-center randomized independent controlled trial, 32 patients were randomized to G1 ( n = 15) or G2 ( n = 17). In G1, laser was given at baseline and then pro re nata (PRN). In G2, three intravitreal bevacizumab (1.25 mg) injections were given once every 6 weeks, then laser and then PRN. Analysis was performed by treatment as administered. This study was registered in clinicaltrials.gov as NCT01572350 and EU Clinical Trial Registry as 2009-014654-15. Results: G2 was superior to G1 improving best corrected visual acuity (BCVA) with respect baseline (+8.0 vs + 3.0; p < 0.01). At month 12, a significantly greater proportion of patients had a BCVA letter score >15 and >73 in G2 (3 of 15 (20%) and 8 of 15 (53%), respectively) versus G1 (1 of 17 (6%) and 4 of 18 (23%), respectively). Health-related quality of life, assessed through National Eye Institute Visual Function Questionnaire, at 12 months was statistically indistinguishable between both groups. Conclusion: G2 provided superior visual acuity gains over G1 in patients with visual impairment due to center-involving diffuse DME, associated with significant gains in VFQ-25 scores.

Pars Plana Vitrectomy with Internal Limiting Membrane Peeling and Intravitreal Bevacizumab Injection for Refractory Diffuse Diabetic Macular Edema

Purpose: Evaluating the impact of pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling and intravitreal bevacizumab (IVB) injection to manage refractory diffuse diabetic macular edema (DME).Methods: In the current prospective interventional clinical study, eyes with refractory diffuse DME with no response to a minimum of three times IVB injections, and best corrected visual acuity (BCVA) of equal or more than 20/200 and equal or lower than 20/60 were subjected to PPV with ILM peeling and intravitreal avastin injection. Pre- and post-operative assessments were a comprehensive ophthalmologic evaluation, fluorescein angiography, and optical coherence tomography (OCT). BCVA, central macular thickness (CMT) and contrast sensitivity (CS) were major outcomes. Results: Fifteen eyes of 13 cases (mean age: 63±5.19 (range, 54-70) years) were subjected to operation and a follow-up of 3 months. Average BCVA at last test was 0.74 ± 0.19 LogMAR that showed no improvement compared with its value before intervention (0.84 ± 0.14 LogMAR) (P=0.073). Average CMT at last test was 328.26±129 µm that was significantly lower compared with its value before operation (450.8±114 µm) (P=0.002) and a significant improvement in CS was found (from 16.66 ± 8.99 mm to 18.13 ±1.22mm;p=0.003). CMT and BCVA (correlation coefficient =0.419,p=0.120), BCVA and CS (correlation coefficient =-0.336,p=0.221) , and CS and CMT (correlation coefficient =-0.07,p=0.979) were found with no significant correlation. Conclusion: PPV with ILM peeling and IVB regarding refractory diffuse DME reduced macular width along with CS improvement, but does not significantly improve visual acuity.

Intravitreal Avastin as a Treatment of Diffuse Diabetic Macular Edema

Background: Macular edema, defined as retinal thickening within 2 disc diameters of the center of the macula, results from retinal microvascular changes that compromise the blood-retinal barrier, causing leakage of plasma constituents into the surrounding retina and, consequently, retinal edema. Focal edema is associated with hard exudate rings caused by leakage from micro aneurysms. Diffuse edema is caused by leakage from micro aneurysms, retinal capillaries, and arterioles. Avastin (Bevacizumab) is a recombinant humanized monoclonal IgG1 antibody that binds to and inhibits the biologic activity of human vascular endothelial growth factor (VEGF). It contains human framework regions and the complementaritydetermining regions of a murine antibody that binds to VEGF. Avastin produced in a Chinese Hamster Ovary mammalian cell expression system in a nutrient medium containing the antibiotic gentamicin and has a molecular weight of approximately 149 kilo Daltons. Purpose: To assess the anatomic effect and visual acuity response after intravitreal (Avastin) in patients with diffuse diabetic macular edema. Patients and Methods: This study included 15 eyes of15 Patients with stable diabetes mellitus with diffuse diabetic macular edema. All eyes had received some form of argon laser photocoagulation (pan retinal photocoagulation (PRP), Focal or Grid of duration not less than 6 months. Mean age of 59 years treated with two intravitreal injections of Avastin 1.25 mg in 0.05 ml six weeks apart. Patients were examined by experienced ophthalmologist visual acuity, evaluation of diabetic retinopathy, central macular thickness by optical coherence tomography each was evaluated at the begging of study (baseline) and follow-up visits. Results: 15 eyes of 15 diabetic patients with persistent diffuse macular edema with no improvement in visual acuity. All the patients received two injections of A vastin six weeks apart. No complications were observed in any patient. The mean baseline visual acuity was (log Mar=1.338±0.455) and the mean visual acuity at three months following the second intravitreal injection was (log Mar=1.094±0.254), the mean central macular thickness at baseline was 492 µm decreased to 369 µm at the end of three months. Conclusions: A vastin resulted in a significant decrease in macular thickness and improvement in visual acuity at three months after the second injection.