RESUMO
<p><b>OBJECTIVE</b>To determine the relationship between velocimetric parameters by using color Doppler ultrasonography and microvessel density (MVD) in papillary thyroid carcinoma and its clinical significance for preoperative diagnosis of papillary thyroid carcinoma. Methods Twenty-nine thyroid tumors were examined preoperatively by color Doppler ultrasonography. The velocimetric parameters including peak systolic velocity (V(max)), end-diastolic velocity (V(min)) were evaluated respectively and resistance index (RI) was calculated. Immunohistochemistry was applied by using polyclonal rabbit anti-human Von Willebrand factor in all cases after operation and microvessel density was calculated based on it.</p><p><b>RESULTS</b>Of the twenty-nine patients who underwent surgery, seventeen patients were diagnosed in papillary thyroid carcinoma and twelve patients in thyroid adenoma. In velocimetric analysis, the RI was significantly higher in patients with papillary thyroid carcinoma than those with thyroid adenoma (t = 3.3108, P < 0.01). V(max) and Vmin were no significance in those two tumors respectively (Z = 0.9520, P > 0.05; Z = - 1.6618, P > 0.05). MVD was also significantly increased in patients with papillary thyroid carcinoma (t = 8.1991, P < 0.01). There was a significant positive association between RI and MVD (r = 0.7924, P < 0.01).</p><p><b>CONCLUSIONS</b>Color Doppler ultrasonography could well display the blood flow of thyroid tissue and its nodules. The velocimetric parameter RI was higher in papillary thyroid carcinoma than in adenoma and was along with its MVD. RI may provide valuable information for diagnosis of papillary thyroid carcinoma preoperatively.</p>