Which imaging uses a gamma camera?

• A. MRI
• B. CT
• C. Fluoroscopy
• D. Scintigraphy

Answer: (D)

A gamma camera is used in scintigraphy, a nuclear medicine imaging technique. In scintigraphy, radiopharmaceuticals are given to the patient and localize in specific tissues or organs. These compounds emit gamma rays as they decay, and the gamma camera detects those photons. Inside the camera, a scintillation crystal converts gamma photons into tiny flashes of light, which are then turned into electrical signals by photomultiplier tubes and translated into an image showing how the tracer is distributed. This provides functional information about processes in the body, not just anatomy. The other options don’t use a gamma camera: MRI relies on magnetic fields and radiofrequency signals; CT uses rotating X-ray beams to create anatomical cross-sections; fluoroscopy uses continuous X-rays for real-time motion imaging. So the modality that uses a gamma camera is scintigraphy.