Current medical and surgical therapeutic approaches to cystoid macular edema in uveitis

Cystoid macular edema (CME), a frequent complication of uveitis, is defined as central retinal thickening caused by accumulation of intra-retinal fluid in the outer plexiform and inner nuclear layers of the retina. Chronic retinal edema can lead to vision loss secondary to photoreceptor impairment and retinal pigment epithelium dysfunction. Patients suffering from CME often complain of decrease in visual acuity, contrast sensitivity and difficulty performing near tasks such as reading. The pathophysiology of CME revolves around disruption of the blood-retinal barrier due to release of pro-inflammatory mediators and/or Muller-cell dysfunction. Imaging modalities have advanced in recent years allowing earlier detection and better management of uveitic CME. Though often managed medically, when CME is refractory to anti-inflammatory therapy such as corticosteroids and/or immunomodulators, underlying mechanical causes such as vitreo-macular traction and internal limiting membrane gliosis must be considered as causes of CME formation. In such cases, Pars-plana vitrectomy with internal limiting membrane peel may be undertaken. New intraoperative imaging modalities, such as intraoperative optical coherence tomography, carry the promise of better and more accurate surgical manipulations.