OPHTHALMOLOGICA

Inflammatory factors involved in DME
disease process

Inflammatory factors that affect vascular permeability may play a role in the aetiology of diabetic macular oedema (DME), a new study’s findings suggest. In 36 patients with DME, enzyme-linked immunosorbent assay showed significantly higher vitreous fluid levels of vascular endothelial growth factor (VEGF), soluble VEGF receptor (sVEGFR)-2, soluble intercellular adhesion molecule (sICAM)-1, monocyte chemotactic protein (MCP)-1 and pentraxin 3 (PTX3) than was present in 15 patients with macular hole. In addition, the patients’ aqueous flare values correlated significantly with their vitreous fluid levels of the inflammatory factors. H Noma et al, “Role of Inflammation in Diabetic Macular Edema”, Ophthalmologica 2014; Volume 232, No 3 (DOI:10.1159/000364955).

Dexamethasone implant shows rapid and sustained effect

In patients with macular oedema secondary to retinal vein occlusion, the intravitreal erodible 700-μg dexamethasone implant Ozurdex provides rapid reductions in central retinal thickness and improvements in BCVA that are sustained throughout the first 90 days following implantation, according to the results of a prospective study. In 19 eyes of 18 patients, mean central retinal thickness decreased rapidly after treatment (p < 0.0001) from 503μm at baseline to 288μm at one day and 199μm at three months. There was an average gain in BCVA of six ETDRS letters at one day and 11 letters at 90 days. D Veritti et al, “Early Effects of Dexamethasone Implant on Macular Morphology and Visual Function in Patients with Macular Edema Secondary to Retinal Vein Occlusion”, Ophthalmologica 2014; Volume 232, No 3 (DOI:10.1159/000366232).

Loss of acuity after switching anti-VEGF agents

Switching AMD patients from ranibizumab to bevacizumab may slightly negate the initial gains achieved with ranibizumab, according to authors of a retrospective study. In 110 eyes with AMD that underwent treatment with ranibizumab on a PRN basis for a mean of 18.1 months, mean BCVA decreased from 54.8 letters to 51.7 letters (p < 0.001) after being switched to bevacizumab for a mean of 12.2 months . However, the authors noted that the natural history of wet AMD could explain the small reduction in visual acuity. J Pinheiro-Costa et al, “Switch from Intravitreal Ranibizumab to Bevacizumab for the Treatment of Neovascular Age-Related Macular Degeneration: Clinical Comparison”, Ophthalmologica 2014; Volume 232, No 3 (DOI:10.1159/000363422).