title: The importance of ophthalmic artery hemodynamics in patients with atheromatous carotid artery disease.
abstract: OBJECTIVE
  The aim of this paper was to provide an insight on the role of the ophthalmic artery blood flow changes due to significant carotid stenosis and the effects of carotid revascularization on the eye and cerebral circulation.
  
  
  METHODS
  An electronic search (Medline) of the English literature was attempted. Measurements of Peak Systolic Velocity (PSV), end-diastolic velocity (EDV), mean velocity (Vmean), Resistance Index (RI) and flow direction, obtained in OA and its branches using transcranial Doppler, in to patients with significant stenosis >70% subjected to surgical or endovascular treatment, or in those with occlusion (unilateral or bilateral), symptomatic or not, in both eyes, prior to or/and after endarterectomy or stenting.
  
  
  RESULTS
  As the degree of internal carotid artery (ICA) stenosis increases, the PSV in ophthalmic artery (OA) decreases. In severe stenoses the flow is not detectable or a reversed flow may be present. Following carotid endarterctomy or stenting, in almost all patients antegrade flow was detected, while in the patients with preoperative antegrade flow, an increase of the velocities was detected postoperatively.
  
  
  CONCLUSIONS
  The reduced blood flow in the OA has consequences in the eye circulation. OA contributes to the collateral pathways in the perfusion of the brain but the importance of this collateral pathway has not been completely clarified.
authors.affiliation: Department of Vascular Surgery, University Hospital of Larissa, Larissa, Greece. katdrakou@yahoo.gr
authors.forename: A A
authors.initials: AA
authors.lastname: Drakou
authors.forename: A G
authors.initials: AG
authors.lastname: Koutsiaris
authors.forename: S V
authors.initials: SV
authors.lastname: Tachmitzi
authors.forename: N
authors.initials: N
authors.lastname: Roussas
authors.forename: E
authors.initials: E
authors.lastname: Tsironi
authors.forename: A D
authors.initials: AD
authors.lastname: Giannoukas
mesh_terms: D001783:Blood Flow Velocity; D002343:Carotid Artery, Internal / Q000503:physiopathology* / Q000601:surgery; D016893:Carotid Stenosis / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery; D002560:Cerebrovascular Circulation; D003097:Collateral Circulation; D016894:Endarterectomy, Carotid; D006439:Hemodynamics; D006801:Humans; D009880:Ophthalmic Artery / Q000503:physiopathology*; D012039:Regional Blood Flow; D012720:Severity of Illness Index