title: Two retinal vein occlusions in a patient with venous tortuosity at the optic disc.
abstract: BACKGROUND
  The aetiology of occlusion is thought to differ for branch retinal vein and central retinal vein types. This communication reports on an unusual presentation of two retinal vein occlusions in one eye of a patient with optic disc tortuosity where the occlusion was thought to occur at a site usually seen in central retinal vein occlusion.
  
  
  METHODS
  An 88-year-old woman presented with sudden-onset painless loss of central vision. Fundal examination of the affected eye revealed one infero-temporal retinal vein occlusion affecting the macula and a second vein occlusion affecting the supero-nasal quadrant with associated optic disc tortuosity. She was investigated for cardiovascular risk factors.
  
  
  RESULTS
  Treatment had already been started for systemic hypertension and blood markers were unremarkable. Conservative management was recommended. 12 weeks later, fluorescein angiography showed no ischaemia.
  
  
  CONCLUSIONS
  We report an unusual case of two co-existent and opposing retinal vein occlusions where obstruction was thought to occur at the trunk of the central retinal vein at or near the level of the lamina cribrosa, a site usually associated with the formation of hemi-vein or central retinal vein occlusion. This had occurred as a result of tortuous vasculature at the optic disc. This unusual case lends weight to previously suggested hypotheses of retinal vein occlusion.
authors.affiliation: Department of Ophthalmology, Kings College Hospital, Denmark Hill, SE5 9RS London, UK. jaheedkhan@yahoo.co.uk
authors.forename: Jaheed
authors.initials: J
authors.lastname: Khan
authors.forename: Victor
authors.initials: V
authors.lastname: Chong
mesh_terms: D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure; D005260:Female; D005451:Fluorescein Angiography; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000188:drug therapy; D009898:Optic Disk / Q000098:blood supply*; D012169:Retinal Vein / Q000473:pathology*; D012170:Retinal Vein Occlusion / Q000175:diagnosis / Q000209:etiology*
chemical_list: D000959:Antihypertensive Agents