Intravitreal bevacizumab [avastin] versus triamcinolone acetonide for treatment of diffuse diabetic macular edema

ABSTRACT

To evaluate and compare the anatomical [central macular thickness] and the functional [visual acuity] outcomes associated with a single intravitreal injection of bevacizumab [Avastin] versus triamcinolone acetonide for the treatment of diffuse diabetic macular edema. The study included 74 eyes [56 patients] with diffuse diabetic macular edema, which were randomized into 2 groups according to the line of treatment used; bevacizumab group [group B] and triamcinolone group [group T]. The inclusion criteria are diffuse diabetic macular edema with fluorescein angiography evidence and central macular thickness [CMT] of at least 400u as measured by OCT. All eyes were subjected to complete ophthalmic examination, including best corrected visual acuity [BCVA] with the logarithm of minimal angle of resolution [log MAR], lOP and fundus biomicroscopy. Fundus photography of the macular region, fundus fluorescein angiography and OCT were performed for all eyes at baseline. 1.SmgIO.6m1 of bevacizumab or 4mgIO.lml of triamcinolone acetonide was injected into the vitreous cavity using a 27-gauge needle inserted through the inferotemporal pars plana 3.5mm from the limbus Patients were scheduled for follow-up examinations at 1, 4, 8, 12 and 24 weeks postoperatively. The outcome measures are the changes in CMT, changes in BCVA and any reported complication. There was no significant difference between the baseline mean CMT and mean BCVA [log MAR] of both groups [p>0.05]. Four weeks following the intravitreal injecthin, there was significant improvement in the mean CMT of both groups, but the difference between both groups was not statistically significant. The mean BCVA [log MAR] was significantly improved in both groups [p<0.05]. At 12 weeks, the mean CMT was still better than baseline in both groups, but this improvement was significant in group T only. The difference between both groups was statistically significant [p < 0.05]. The mean BCVA [log MAR] was significantly better in both groups and this improvement was significantly better in group T also. At 24 weeks, the mean CMT has increased to approximate the baseline again with a corresponding deterioration in the mean BCVA in both groups. In group T, the mean TOP was increased throughout the study and the maximum increase was reported at the 4th week [p < 0.05]. In group B, no significant change in the mean TOP was reported during the follow-up period. A single intravitreal injection of triamcinolone acetonide may be associated with greater beneficial effects on vision and central macular thickness than a single intravitreal injection of bevacizumab for the short-term management of diffuse diabetic macular edema. However, careful monitoring of the TOP should be done in eyes receiving triamcinolone acetonide