This image shows enlargement of the thyroid gland and extension down behind the breastbone (retrosternal space). The image, called a scintiscan, was generated using a radioactive isotope.
Review Date: 5/31/2013 Reviewed By: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.