Abstract
Diabetic macular oedema (DMO) is a major cause of visual loss in diabetes, with a complex multifactorial pathogenesis. In the UK alone it is estimated that there are nearly 2.5 million diabetic patients aged over 12 years. Approximately 65,000 of these have clinically significant DMO that affects their visual acuity in at least one eye [1]. In DMO, the final common pathway is disruption of the blood-retinal barrier (BRB), resulting in leakage of fluid into the retinal layers, but causation is complicated, with many factors contributing to the process. Nevertheless, evidence is mounting that inflammation is implicated in BRB breakdown, together with hypoxia, alterations in blood flow and retinal ischaemia.