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[Arteriovenous crossing sheathotomy in branch retinal vein occlusion].

BACKGROUND
The aim of this study is to report on arteriovenous sheathotomy in branch retinal vein occlusion (BRVO) with a long-term follow-up and examine the visual field effects of this surgical approach.


PATIENTS AND METHODS
In a clinical trial 36 eyes with branch retinal vein occlusion (22 eyes with ischaemia, 14 eyes with chronic macular oedema) underwent surgical decompression accompanied by peeling of the membrana limitans interna after prior isovolemic haemodilution for 3 months had been unsuccessful.


RESULTS
All eyes showed a significant reduction of macular oedema 3 months after surgery. During follow-up (median: 26.4 months) visual acuity increased in 24/36 eyes and was stabilised in 8/36 eyes. We observed haemorrhages at the dissection site (5x), vitreous haemorrhages (12x) and retinal holes at the vitreous base (2x). Goldmann perimetry revealed paracentral scotomas in 3 eyes, which had been treated by arteriovenous dissection relatively close to the optic disc. In 16/22 eyes with ischaemic thromboses the visual field was narrowed in the affected quadrant.


CONCLUSIONS
The results of arteriovenous sheathotomy in BRVO are encouraging because we observed increase of visual acuity in 67% of the eyes in spite of an unsuccessful haemodilution during 3 months before. However, whether its benefits outweigh potential surgical complications as visual field defects remains to be determined.