title: Branch retinal vein occlusion in an asymptomatic adult with cystic fibrosis.
abstract: OBJECTIVE
  This article aims to describe a case of asymptomatic branch retinal vein occlusion (BRVO) in a patient with cystic fibrosis (CF) and discuss the possible link between the two.
  
  
  METHODS
  A young adult (aged 35 years) with CF who presented for routine ocular examination was found to have a superior temporal BRVO in the left eye. Visual acuity was unaffected, measuring -0.06 LogMAR, and intraocular pressure was 10 mm Hg. Optical coherence tomography showed no macular involvement. Regarding the patient's general health, blood pressure was within the normal range, and there was no diabetes. Exploratory blood tests revealed elevated fibrinogen levels.
  
  
  CONCLUSIONS
  It is hypothesized that BRVO occurred secondary to raised fibrinogen levels, a common feature in CF resulting from chronic pulmonary infection and inflammation. Practitioners should be aware of the possible link between BRVO and CF.
authors.affiliation: *PhD †FRCP, PhD School of Optometry and Vision Sciences (RJH, CP, RVN, KSEE), Cardiff University, Cardiff, Wales, United Kingdom; and All Wales Adult Cystic Fibrosis Centre (IK), University Hospital, Llandough, Cardiff, Wales, United Kingdom.
authors.forename: Rachel J
authors.initials: RJ
authors.lastname: Hiscox
authors.forename: Christine
authors.initials: C
authors.lastname: Purslow
authors.forename: Rachel V
authors.initials: RV
authors.lastname: North
authors.forename: Ian
authors.initials: I
authors.lastname: Ketchell
authors.forename: Katharine S E
authors.initials: KS
authors.lastname: Evans
mesh_terms: D000328:Adult; D001794:Blood Pressure; D003550:Cystic Fibrosis / Q000150:complications* / Q000175:diagnosis; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D012170:Retinal Vein Occlusion / Q000175:diagnosis / Q000209:etiology*; D013927:Thrombosis / Q000209:etiology; D014792:Visual Acuity / Q000502:physiology
chemical_list: D005340:Fibrinogen