OBJECTIVETo investigate the diagnostic value of ultrasonography for diffuse thyroid disease accompanied with suspicious nodules.

METHODSA total of 148 patients with diffuse thyroid diseases accompanied with suspicious nodules underwent both ultrasonography and ultrasound-guided biopsy, and the results were analyzed and compared.

RESULTSAmong these 148 patients, 44 had Hashimoto's thyroiditis and 104 had Graves'disease. Totally 151 suspicious lesions were detected by ultrasonography, among which 48 lesions were pathologically confirmed to be benign and 103 malignant. Thirteen malignant lesions were diagnosed as benign by pre-operative ultrasonography, which were confirmed to be malignant after the surgical resection due to other suspected or confirmed malignant lesions. The detection rate of diffuse thyroid disease accompanied with thyroid cancer by per-operative ultrasound was 68.21%, and the misdiagnosis rate was 31.79%. The gender of patients(P=0.36), number of nodules(P=0.08), and blood flow types in lesions(P=0.080) had no significant difference between the benign and malignant groups, whereas internal echo(P=0.040), margin(P=0.000), shape(P=0.001), and calcification features(P=0.000)showed significant differences. Up to 80.74% of the lesions with hyperechoic calcification were malignant.

CONCLUSIONSGray-scale sonographic features are helpful for the differential diagnosis of nodules in patients with diffuse thyroid diseases. Nodules in the isthmus and those accompanied with multiple nodules should be noticed.