|Classification and external resources|
Macular edema occurs when fluid and protein deposits collect on or under the macula of the eye (a yellow central area of the retina) and causes it to thicken and swell (edema). The swelling may distort a person's central vision, as the macula is near the center of the retina at the back of the eyeball. This area holds tightly packed cones that provide sharp, clear central vision to enable a person to see detail, form, and color that is directly in the direction of gaze.
Cystoid macular edema (CME) involves fluid accumulation in the outer plexiform layer secondary to abnormal perifoveal retinal capillary permeability. The edema is termed "cystoid" as it appears cystic; however, lacking an epithelial coating, it is not truly cystic. The etiology for CME can be remembered with the mnemonic "DEPRIVEN" (Diabetes, Epinepherine, Pars planitis, Retinitis pigmentosa, Irvine-Gass Syndrome, Venous occlusion, E2-prostaglandin, Nicotinic acid and Niacin).
Diabetic macular edema (DME) is similarly caused by leaking macular capillaries. DME is the most common cause of visual loss in both proliferative, and non-proliferative diabetic retinopathy.
Iluvien, a sustained release intravitreal implant developed by Alimera Sciences, has been approved in Austria, Portugal and the U.K. for the treatment of vision impairment associated with chronic diabetic macular edema (DME) considered insufficiently responsive to available therapies. Additional EU country approvals are anticipated.
A 2010 Cochrane Systematic Review studied the effectiveness of two anti-VEGF treatments, ranibizumab and pegaptanib, on patients suffering from macular edema caused by CRVO. Participants on both treatment groups showed a reduction in macular edema symptoms over six months.
- "GEN | News Highlights: FDA Green-Lights Genentechâ€™s Lucentis for Macular Edema following Retinal Vein Occlusion". Genengnews.com. Retrieved 2012-12-15.
- "Iluvien gains marketing authorization in Portugal for chronic DME". OSN SuperSite, June 7, 2012. Retrieved June 20, 2012
- "Steroid Injections vs. Standard Treatment for Macular Edema Due to Retinal Blood Vessel Blockage - Full Text View". ClinicalTrials.gov. Retrieved 2012-12-15.
- Braithwaite T, Nanji AA, Greenberg PB (2010). "Anti-vascular endothelial growth factor for macular edema secondary to central retinal vein occlusion". Cochrane Database Syst Rev 10: CD007325. doi:10.1002/14651858.CD007325.pub2. PMID 20927757.