Skip to main content
. Author manuscript; available in PMC: 2013 Oct 1.
Published in final edited form as: Microcirculation. 2012 Oct;19(7):619–631. doi: 10.1111/j.1549-8719.2012.00197.x

Figure 2. In vitro relationship between normalized speckle index (NSI, arbitrary units, a.u.) and absolute average velocity.

Figure 2

A) Glass capillary diameter was increased to approximately 2- (282μm) and 3- (447μm) fold of the initial 142μm diameter with no significant variation in the NSI-velocity relationship (3ms exposure). B) Increasing hematocrit from 36% PCV to 54% PCV demonstrated no significant variation in the NSI-velocity relationship (3ms exposure). C) The linear dynamic range (in log-log scale) of the in vitro NSI-velocity relationship can be shifted by adjusting exposure rate from 3ms exposure (open circles) to 20ms exposure (closed circles). Linear relationship (log-transformed) is displayed with dotted lines (20ms, circles, excludes last 4 non-linear values; 3ms, cross-hatches, excludes first 4 non-linear values).