8 research outputs found
Sensitivity and Specificity of PW-Doppler parameters t<sub>s</sub>/t<sub>T</sub> and v<sub>max</sub> as predictors of plaque formation.
<p>Sensitivity and Specificity of PW-Doppler parameters t<sub>s</sub>/t<sub>T</sub> and v<sub>max</sub> as predictors of plaque formation.</p
Changes in Lumen and IEL area upon carotid constriction.
<p>Data was analyzed by One Way ANOVA.</p><p>â*âindicates p<0.05 as compared to presurgery.</p>ââ â<p>indicates p<0.05 as compared to 2 weeks post surgery.</p
Plaque length is accurately measured by ultrasound.
<p>(a) Representative sagittal B-mode images of RCCA from one animal prior to surgery (0) and 3, 6 and 9 weeks after cast placement. Plaque length is indicated with arrows. (b) Whole mount of the carotid artery in (a) at study termination. (c) Linear regression of ultrasound vs microcaliper measurements of plaque length (nâ=â6 cuffs, 10 casts). Dotted lines indicate 95% confidence intervals. Correlation coefficientâ=â0.92, nâ=â16. (d) Bland Altman analysis of plaque length as measured by microcaliper and UBM. Dotted lines represent 95% limits of agreement. Bias, indicated by solid line, was calculated as â0.27 mm+/â0.22 SD.</p
Percent stenosis calculated from UBM parameters correlates with histological measurements.
<p>(a) Transverse B-mode image of RCCA 2 and 9 weeks after surgery. Upper Images, Adventitia is marked âAâ, plaque âPâ, âMedial layer Mâ. Lower, images are identical, but the inner elastic lamina is outlined with dotted white line, lumen with a red dotted line. Trichrome-stained transverse sections of the same 9 wk artery; internal elastic lamina (IEL) and lumen are outlined in white and red, respectively. (b) IMT measurements of casted and cuffed animals after 2 and 9 weeks of surgery. n.s. Not significant. (c) Linear regression analysis of percent stenosis estimated by UBM and histology. See Materials and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029944#s2" target="_blank">Methods</a> for calculations of percent stenosis. Dotted lines indicate 95% confidence intervals; correlation coefficientâ=â0.75, nâ=â10 casts. (d) Comparison of UBM and histology measurements using Bland-Altman analysis. Dotted lines indicate 95% limits of agreement. Bias is indicated by solid line, was calculated as â4.76 mm±13.3 SD.</p
Plaques Progress More Rapidly in Casted vs Cuffed Animals.
<p>The rate of plaque growth was determined by performing individual linear regression analysis of plaque length or stenosis over time for each animal. The slopes (rates) were compared by unpaired t-test. (a) Rate of plaque growth in length (b) Rate of plaque growth in terms of stenosis. Data are mean±SEM, nâ=â7 cuffs, 10 casts â*â indicates p<0.05. (See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029944#pone.0029944.s002" target="_blank">Fig. S2</a> for source data.)</p
Pre-plaque PW-Doppler parameters correlate with plaque length at 9 weeks.
<p>(a) Representative PW-Doppler tracing of a proximal RCCA before and after surgery. Note the dramatic decrease in velocity. Measurements of v<sub>max</sub>, time in systole (t<sub>s</sub>) and t<sub>T</sub> (total time) are indicated. (b) v<sub>max</sub> and t<sub>s</sub>/t<sub>T</sub> were calculated from pre-surgery tracings and 2 and 9 weeks after device placement. Data (mean±SEM, nâ=â7 cuffs, 10 casts), were analyzed by 2 way ANOVA. There was a highly significant effect of device on v<sub>max</sub> and t<sub>s</sub>/t<sub>T</sub> ratio (p<0.005), but no significant difference between cast and cuffs on either parameter. â*â p<0.05 compared to pre-surgery. (c) Using 39 animals fitted with casts, 2 week t<sub>s</sub>/t<sub>T</sub> and v<sub>max</sub> values were calculated and plotted against plaque length at 9 weeks and the correlation determined by linear regression. t<sub>s</sub>/t<sub>T</sub> positively correlated with plaque length (p<0.0005, râ=â0.66) between, v<sub>max</sub> and plaque length were negatively correlated (p<0.0005, râ=â0.59). Dotted lines indicate 95% confidence interval.</p