Macular edema formation and deterioration of retinal function after intravitreal bevacizumab injection for proliferative diabetic retinopathy

Abstract

Purpose: To report a case of proliferative diabetic retinopathy (PDR) showing transient macular edema (ME) and deteriorated retinal function after intravitreal bevacizumab injection (IVB).

Methods and results: A 53-year-old man received IVB (1.25 mg/0.05 ml) in both eyes for the treatment of PDR. There was no treatment-related complication. However, he complained of photopsia in both eyes 6 h after the injection. Slit-lamp examination revealed mild cellular infiltrations (1+) in the anterior chamber in both eyes. Optical coherence tomography showed ME formation in the left eye. Both full-field and multifocal electroretinography (ERG) revealed the deterioration of all parameters in both eyes compared with pretreatment. The inflammation in the anterior segment and ME disappeared 1 day after the injection. ERG parameters were improved 9 days after the injection, except for the N1 and P1 amplitude of multifocal ERG in the left eye.

Conclusion: We propose that patients who undergo IVB should be carefully informed and followed up for possible complications including temporal ME formation and retinal function deterioration.

Keywords: Anti-vascular endothelial growth factor; Avastin; Bevacizumab; Diabetic retinopathy; Full-field electroretinography; Macular edema; Multifocal electroretinography; Optical coherence tomography.

Fig. 1

Late-phase fluorescein angiography findings. a Leakages from neovascularizations on the disc and elsewhere were seen before IVB in both eyes. b Leakages from neovascularizations were reduced 9 days after the injection.

Fig. 2

Upper panel: transition of retinal thickness and total macular volume in OCT. Lower panel: transition of the horizontal line and the color map image of retinal thickness in OCT. Before the injection, OCT findings showed normal macular appearances in both eyes. The retinal thickness and total macular volume in the left eye were increased 6 h after the injection. OCT findings in the left eye improved after 1 day and were kept normal after that. OCT findings in the right eye were kept normal during the follow-up period.

Fig. 3

Transition of ERG parameters. Upper panel: transition of full-field bright-flash ERG. Lower panel: transition of multifocal ERG at 3 central rings of 103 hexagon analysis. In both methods, all ERG parameters worsened 6 h after the injection and improved with time, except for the N1 and P1 amplitudes of the left eye.