title: Forearm arterial anatomy and flow characteristics: a prospective observational study.
abstract: BACKGROUND
  Morphometric data on Caucasian radial and ulnar arteries are limited, with no data on flow interdependence in the forearm arterial circuit.
  
  
  METHODS
  A total of 250 upper extremities in 125 patients were evaluated. Ultrasonography was performed and radial and ulnar artery lumen diameters were measured. Ulnar artery (UA) was compressed at the level of the wrist, and flow parameters in radial artery (RA) were recorded using duplex Doppler ultrasound.
  
  
  RESULTS
  Radial and ulnar artery diameters were comparable at the level of the distal forearm (RA = 2.03 ± 0.28 mm, UA = 2.07 ± 0.27 mm; P=.14). There was no significant difference in radial or ulnar artery diameter between the dominant upper extremity and the non-dominant upper extremity. Upon compression of the ulnar artery, radial artery velocity-time integral (VTI) increased from 8.4 ± 3.8 cm to 12.8 ± 5.5 cm, which was statistically significant (P<.001). There was a significant inverse correlation between radial artery diameter and the magnitude of increase in radial VTI observed with UA compression (r² = 0.106; P<.001).
  
  
  CONCLUSIONS
  RA diameter at the level of the distal forearm is comparable to UA. RA-VTI and likely flow significantly increase by compression of the UA. The smaller the radial artery, the larger the increase in radial artery flow with ulnar compression.
authors.affiliation: Wright Center for Graduate Medical Education, The Commonwealth Medical College, Scranton, Pennsylvania, USA. pancholy8@gmail.com.
authors.forename: Samir B
authors.initials: SB
authors.lastname: Pancholy
authors.forename: Laura A
authors.initials: LA
authors.lastname: Heck
authors.forename: Tejas
authors.initials: T
authors.lastname: Patel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D005260:Female; D005542:Forearm / Q000098:blood supply*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D017534:Radial Artery / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology*; D017535:Ulnar Artery / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D018616:Ultrasonography, Doppler, Duplex; D055815:Young Adult