"Fish-eye sign" in scintigraphy of benign thyroid nodule

An unusual scintigraphic appearance of a benign adenomatous nodule in the thyroid is described which showed a central core of functional tissue surrounded by a rim of nonfunctioning tissue and degenerative changes. The descriptive term "fish-eye sign" is proposed. The characterization of tissue by scintigraphy prior to fine needle aspiration may be helpful in its interpretation.