scintigrafie

Scintigraphy is a nuclear medicine imaging technique that uses small amounts of radioactive tracers, or radiopharmaceuticals, to visualize the function and distribution of organs and tissues within the body. After administration, the tracer accumulates in specific sites according to biological processes, and a gamma camera detects the emitted radiation to create images. Planar scintigraphy provides two-dimensional images, while techniques such as single-photon emission computed tomography (SPECT) produce three-dimensional data; hybrid SPECT/CT combines functional information with anatomical reference from computed tomography.

The radiotracers used in scintigraphy are chosen to target particular organs or pathophysiological processes. Technetium-99m compounds are the most commonly used due to their favorable physical properties. Other isotopes include iodine-123 or iodine-131 for thyroid imaging, thallium-201 or other agents for perfusion studies, and indium-111 or gallium-67 for various organ evaluations. The radiotracer is typically given by injection, oral administration, or another route depending on the study, and images are acquired after a suitable uptake period.

Common clinical applications include bone scintigraphy for detecting metastatic disease and fractures, thyroid scans for evaluating nodules and thyroid function, myocardial perfusion scintigraphy for ischemia and infarction assessment, renal scintigraphy for perfusion and drainage, and hepatobiliary scintigraphy for biliary tract patency. Additional functional studies exist for gastric emptying and sentinel lymph node mapping in cancer.

Safety and interpretation: Scintigraphy provides important functional information with generally low radiation exposure, but it requires access to a radiopharmacy and a gamma camera. The images are interpreted by a nuclear medicine physician in the clinical context, and results may be complemented by anatomical imaging for precise localization.