[Recurrence of macular edema complicating central retinal vein occlusion: Consider follow-up fluorescein angiography]

The goal of our study is to highlight, through a series of 4 cases, the importance of retinal fluorescein angiography in monitoring the retinal periphery in retinal vein occlusions, particularly in cases of recurrent macular edema.

This is a series of 4 patients aged between 50 and 90 years with ischemic central retinal vein occlusions in 2 cases and branch retinal venous occlusions in 2 cases. Fluorescein angiography was performed in two of our patients, and optical coherent tomography in all cases, showing cystoid macular edema with an average macular thickness of 439μm. All patients received a complete etiological assessment and intravitreal anti-VEGF injections with an initially favorable course in all cases. A recurrence with aggravation of the edema compared to the initial appearance was observed in all cases, with a delay varying between 9 and 16 months (mean 11.25 months). Fundus examination revealed an increased number of retinal hemorrhages in each case, with the appearance of cotton wool spots in one case, suggesting ischemic conversion. This was confirmed by performing fluorescein angiography, which revealed large areas of retinal ischemia. Retinal photocogulation of the ischemic areas was thus indicated, along with a second series of intravitreal injections.

Macular edema is the principal cause of visual acuity decline in retinal vein occlusions; its prognosis is similar to that of retinal venous occlusions in general, hampered by the possibility of ischemic conversion. The diagnosis of retinal vein occlusion is clinical and does not require angiography. This remains, however, a useful exam to better analyze the retinal periphery as well as for the detection of various modalities during spontaneous progression.