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Vitrectomy for non-ischaemic macular oedema in retinal vein occlusion.

PURPOSE
To evaluate the effect of vitrectomy in eyes with non-ischaemic macular oedema secondary to hemi and central retinal vein occlusion.


METHODS
This retrospective study analysed the outcome of eight patients with non-ischaemic macular oedema without posterior vitreous detachment. Six patients had a central retinal vein occlusion and two had a hemi retinal vein occlusion. A standard three-port vitrectomy was performed in all patients. Retinal mapping by optical coherence tomography and visual acuity (VA) testing were performed before vitrectomy and at 1, 2 and 12 months postoperatively.


RESULTS
At the 1-month follow-up there was a statistically significant reduction in retinal thickness (Wilcoxon; p = 0.04) that persisted at 2 months (Wilcoxon; p = 0.04). However, at 12 months there was no difference compared with baseline. LogMAR VA was significantly improved at 1 month (Wilcoxon p = 0.04), but at 2 and 12 months there was no difference compared with baseline.


CONCLUSIONS
Vitrectomy in hemi and central retinal vein occlusion has the potential to reduce macular oedema and improve VA in the early postoperative phase but does not seem to improve the longterm outcome of the disease.