To evaluate the contrast enhanced perfusion pattern of PTC micro-vascular imaging (MVI) quantitatively. Investigate the correlation between PTC MVI features and CD34 micro-vascular density (MVD).

Thirty-nine pathological and clinical confirmed sporadic PTCs were evaluated with real-time gray-scale contrast-enhanced micro-vascular imaging under a low mechanical index. The micro-bubble agent was SoneVue. Of the 39 PTCs, 33 were classical PTCs, 6 were PTC with follicular variant (FVPTC). The △ROI ,which is the subtraction of peak echo intensity between the lesion region of interest (ROI) and normal thyroid parenchyma ROI, was used to evaluate the perfusion characteristics of PTC MVI quantitatively. The paraffined specimens were selected for immunohistochemical (IHC) staining for CD3, and the correlation between △ROI and the CD34 were evaluated.

△ROI was strongly correlated with the CD34 expression (P=0.000), significant differences were detected in the distribution pattern of △ROI value among different CD34 expression levels, no overlapping of the mean △ROI values and the 95% confidence intervals was found among the 3 CD34 expression levels. The PTC MVI perfusion was classified into 3 patterns, low perfusion, focal perfusion and high perfusion, on the basis of combining △ROI values with the peak ehco pattern in time-intensity curve.

The △ROI is strongly correlated with the CD34 expression in papillary thyroid cancer. It can be used for the quantitative evaluation of PTC MVI pattern and intensity as an objective indicator.