PURPOSE. TO describe a case of branch retinal vein occlusion (BRVO) in a pa
tient who tested positive for the 20210 A allele of the prothrombin (PT) ge
ne.
METHODS. A 48-year-old man had visual loss in the right eye secondary to BR
VO confirmed by ophthalmoscopy and fluorescein angiography. His medical his
tory was not remarkable for common risk factors for retinal occlusive disea
ses.
RESULTS. Laboratory tests for hypercoagulability were positive for PT 20210
A variant. The patient's family tested negative for the PT variant.
CONCLUSIONS. Laboratory tests for coagulopathy, including the PT 20210 A va
riant, should be added to the examination of patients with central or BRVO,
especially if most common risk factors for thrombosis have been excluded.