Figure 2.

Study population (A) and representative ultrasonography (B–G). A, Patients were stratified by serum TSH and imaging. *, Tumors of nonthyroid origin included 2 thyroglossal duct cysts, 1 Burkitt lymphoma, 1 high-grade peripheral nerve sheath tumor, 1 undifferentiated sarcoma, 1 benign parathyroid cyst, 1 renal clear cell sarcoma metastasis, 1 ganglioneuroma, and 1 ectopic thymic rest. Three patient ultrasound studies are shown. B and C, Transverse (B) and sagittal (C) images of Hashimoto's thyroiditis, characterized by diffuse heterogeneity of the entire gland and a thickened isthmus (calipers; 1.04 cm) without a discrete nodule. D and E, Transverse (D) and sagittal (E) images of the diffuse sclerosing variant of papillary thyroid cancer, characterized by innumerable punctate echogenicities without a focal lesion. F and G, Transverse (F) and sagittal (G) images of a well-defined, complex (<25% cystic) nodule (calipers) with surrounding normal thyroid. T, trachea.