Which imaging modality commonly requires lead shielding due to radiation exposure?

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

Answer: (D)

Lead shielding is used to limit exposure from ionizing radiation. MRI uses magnetic fields, and ultrasound relies on sound waves, so they do not involve ionizing radiation and don’t require shielding for radiation protection. Scintigraphy involves radioactive material, so safety protocols exist for handling and protecting staff, but during imaging the shielding emphasis is less about patient protection and more about occupational safety. Fluoroscopy and CT deliver ionizing radiation in real time or with high-dose exposure, making lead shielding a standard protective measure to protect staff and, when appropriate, parts of the patient. That combination of continuous or substantial radiation exposure is why this modality pair is the one that commonly requires lead shielding.