title: Microemboli are not a prerequisite in retinal artery occlusive diseases.
abstract: OBJECTIVE
  Retinal artery occlusion (RAO) is caused by arterio-arterial or cardiovascular emboli in about 50% of all cases, but the role of non-embolic causes remains unclear.
  
  
  METHODS
  We studied 27 patients with amaurosis fugax (AFX), branch retinal artery occlusion (BRAO), central retinal artery occlusion (CRAO) and anterior ischaemic optic neuropathy (AION). Patients underwent an evaluation of cerebrovascular and cardiovascular risk factors, measurement of haemorheological parameters, and Doppler/duplex sonography including ultrasound detection of cerebral microembolic signals and echocardiography.
  
  
  RESULTS
  Forty-one per cent of the patients had internal carotid atherosclerosis but only one patient had microembolic signals, probably due to a cardiac thrombus. Vascular risk factors, especially hypertension, were present in 82% of the patients correlating with abnormal haemorheological parameters such as increased thrombocyte reactivity.
  
  
  CONCLUSIONS
  Our results indicate that altered haemorheological parameters, especially increased thrombocyte reactivity and vascular risk factors such as arterial hypertension, are non-embolic causes of vascular disease in a significant number of patients with RAO. This should guide diagnostic and therapeutic considerations concerning RAO in cases without proven embolic sources.
authors.affiliation: Department of Neurology, University Hospital of Münster, Germany.
authors.forename: C G
authors.initials: CG
authors.lastname: Haase
authors.forename: T
authors.initials: T
authors.lastname: Büchner
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004617:Embolism / Q000150:complications*; D005260:Female; D006331:Heart Diseases / Q000150:complications; D018056:Hemorheology; D006801:Humans; D006937:Hypercholesterolemia / Q000150:complications; D006973:Hypertension / Q000150:complications*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D010974:Platelet Aggregation; D015356:Retinal Artery Occlusion / Q000097:blood / Q000209:etiology*; D012307:Risk Factors