(a) gray scale ultrasound, transverse scan showing normal thyroid anatomy, (b) arterial vascularization of the thyroid gland. In our experience, most benign thyroid nodules are either purple or green. Pin On Endocrinology Class i, prevalence of red and green color; Abnormal thyroid cancer ultrasound colors . Patients with thyroid nodules and differentiated thyroid cancer. Nodules were classified into four classes: In the more frequently used color map, the color red represents hard or stiff tissue and the color purple represents soft or elastic tissue. The primary purpose of a thyroid ultrasound is to detect thyroid cancer. A common imaging test used to evaluate the structure of the thyroid gland. Color doppler showed increased vascularity, while the rest of the thyroid showed normal vascularity. However, less than 5% ofâ thyroid nodules are cancerous, meaning that most nodules are benign A thyroid ultrasound may be ordered if a thyroid function test is abnormal o...