title: Spiral Laminar Flow: a Survey of a Three-Dimensional Arterial Flow Pattern in a Group of Volunteers.
abstract: OBJECTIVE
  Spiral laminar flow was suggested as potentially the predominant arterial blood flow pattern many years ago. Computational fluid dynamics and flow rig testing have suggested there are advantages to spiral laminar flow. The aim of this study was to identify whether spiral laminar is the predominant flow pattern in a cohort of volunteers.
  
  
  METHODS
  This study included 42 volunteers (mean age 66.8 years). Eleven arterial sites were examined, comprising bilateral examination of the common carotid artery, internal carotid artery, external carotid artery, common femoral artery, superficial femoral artery, and the infra renal aorta. The presence or absence of spiral laminar flow, the peak systolic velocity, and the rotational velocity were assessed by colour Duplex scanning.
  
  
  RESULTS
  The incidence of spiral laminar flow ranged from 81% in the internal carotid artery to 90% in the common carotid artery and the infra renal aorta. Overall, in 58% of all right-sided arteries the rotation was clockwise and 42% anticlockwise. In all left-sided arteries these numbers were reversed. Analysis on the basis of volunteer rather than examination site showed that 41/42 (97%) had more sites with spiral laminar flow than without. Only one volunteer had more sites exhibiting non-spiral laminar flow.
  
  
  CONCLUSIONS
  Spiral laminar flow was the predominant flow pattern in the study population. This observation raises questions and suggests a need for further studies concerning the form and function of the left ventricle, the geometry of the arterial system, and the function of the arterial wall.
authors: Department of Vascular Surgery, Ninewells Hospital and Medical School, Dundee, UK.
authors: P A
authors: PA
authors: Stonebridge
authors: Department of Vascular Surgery, Ninewells Hospital and Medical School, Dundee, UK. Electronic address: stuartsuttie@nhs.net.
authors: S A
authors: SA
authors: Suttie
authors: Vascular Laboratory, Ninewells Hospital and Medical School, Dundee, UK.
authors: R
authors: R
authors: Ross
authors: Department of Vascular Medicine, Ninewells Hospital and Medical School, Dundee, UK.
authors: J
authors: J
authors: Dick
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries / Q000000981:diagnostic imaging* / Q000503:physiopathology; D001783:Blood Flow Velocity; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D011237:Predictive Value of Tests; D012039:Regional Blood Flow; D018615:Ultrasonography, Doppler, Color / Q000379:methods*
keywords: Arterial flow; Spiral laminar flow