title: Comparison of ocular hemodynamics measured by a new retinal blood flowmeter and color Doppler imaging.
abstract: OBJECTIVE
  To compare measurements of a new retinal blood flow device with central retinal artery blood velocity.
  
  
  METHODS
  One randomly selected eye from each of 13 subjects was examined. Blood flow was measured by laser blood flowmeter and velocity by color Doppler imaging. The correlation between measurements was analyzed using regression analysis where a P value of less than .05 and coefficient of regression values of greater than .5 were considered significant.
  
  
  RESULTS
  The laser blood flowmeter produced vessel diameter measurements of 90.1 +/- 18.7 microm (mean +/- standard deviation), velocity of 19.7 +/- 8.06 mm/sec, and flow measurements of 4.24 +/- 2.41 microL/min. Central retinal artery peak systolic velocity, end diastolic velocity, and mean velocity correlated significantly with laser blood flowmeter velocity (P = .01, r = .66; P < .01, r = .77; and P = .003, r = .76, respectively) and flow (P = .01, r = .71; P = .03, r = .6; and P = .01, r = .69, respectively).
  
  
  CONCLUSIONS
  The laser blood flowmeter produces retinal artery flow and velocity measurements that correlate with central retinal artery peak systolic velocity end diastolic velocity, and mean velocity measurements. Further validation of the laser blood flowmeter's accuracy in measuring real flow warranted and likely requires more invasive in vivo studies (in animal models). However, this study supports the ability of the laser blood flowmeter to measure retinal blood flow.
authors.affiliation: Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
authors.forename: Larry
authors.initials: L
authors.lastname: Kagemann
authors.forename: Alon
authors.initials: A
authors.lastname: Harris
authors.forename: Christian
authors.initials: C
authors.lastname: Jonescu-Cuypers
authors.forename: Rishi
authors.initials: R
authors.lastname: Kumar
authors.forename: Clinton
authors.initials: C
authors.lastname: Sheets
authors.forename: Ehud
authors.initials: E
authors.lastname: Rechtman
authors.forename: Renata
authors.initials: R
authors.lastname: Migliardi
authors.forename: Hanna J
authors.initials: HJ
authors.lastname: Garzozi
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D005123:Eye / Q000098:blood supply* / Q000000981:diagnostic imaging*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007834:Lasers; D008297:Male; D012039:Regional Blood Flow; D012171:Retinal Vessels / Q000502:physiology*; D012212:Rheology; D018615:Ultrasonography, Doppler, Color