Significance of perithyroidal lymph nodes in benign thyroid diseases.

PTLNs were seen in inflammatory thyroid diseases, but were rarely detected in other thyroid diseases. These findings indicate that PTLNs are an indicator for differentiating inflammation of the thyroid. Lower echogenicity of the thyroid, known to correspond to inflammation, showed a correlation with the positive rate of PTLNs. PTLNs in cases of Graves' disease may be due to coexisting thyroiditis related to TgAb and/or TPOAb.