Ultrasound measurement of the effect of temperature on microperfusion in the eye.
Recent developments in ultrasound (US) technology have allowed the study of microperfusion in the anterior segment of the eye. Our aim was to determine the effect of the thermal environment on blood flow in the anterior segment. We measured blood flow in the major arterial circle of five rabbits. A 38-MHz US transducer was coupled to the eye with a normal saline water-bath with temperature controlled from 1 degrees C to 38 degrees C. The major arterial circle was localized and imaged using the swept-scan technique and M-mode data were then acquired for measurement of pulsatile flow. Peak systolic and mean velocity averaged 4.51 and 1.32 mm/s, respectively. Positive correlations were found between peak systolic (1.69%/ degrees C) and mean (1.76%/ degrees C) velocities and temperature. Vessel diameter (mean = 178 microm) did not show any significant change with temperature. High-resolution US flowmetry demonstrated decreasing flow rates in the iris with decreasing temperature.
Silverman
Ronald H
RH
Weill Medical College of Cornell University, New York, NY 10021, USA. prof@boodle.med.cornell.edu
Ursea
Roxana
R
Kruse
Dustin
D
Ferrara
Katherine W
KW
Rondeau
Mark J
MJ
Coleman
D Jackson
DJ
D000818:Animals; D000869:Anterior Eye Segment / Q000098:blood supply / Q000000981:diagnostic imaging; D001783:Blood Flow Velocity; D005123:Eye / Q000098:blood supply* / Q000000981:diagnostic imaging*; D007498:Iris / Q000098:blood supply / Q000000981:diagnostic imaging; D016014:Linear Models; D008833:Microcirculation; D011673:Pulsatile Flow; D011817:Rabbits; D013696:Temperature; D018615:Ultrasonography, Doppler, Color / Q000379:methods