Scintigraphy uses radioactive compounds (radiotracers) that selectively accumulate in specific tissues, allowing visualization of their function and structure. These compounds emit gamma rays detected by a gamma camera, producing images that highlight tissue activity and pathology. This technique is essential for diagnosing metabolic and functional abnormalities in organs like the thyroid, bone, and heart. Unlike ultrasound, MRI, or CT, which rely on physical or magnetic properties, scintigraphy depends on radioactive tracers with tissue affinity to provide targeted, functional imaging.

Reference: Robbins Basic Pathology, Kumar, Abbas, Aster, 10th Edition.