Which imaging modality provides cross-sectional slices of the body using ionizing radiation?

Which imaging modality provides cross-sectional slices of the body using ionizing radiation?

• A. Magnetic resonance imaging
• B. Ultrasound
• C. CT scan
• D. Radiography

Answer: (C)

Cross-sectional imaging using ionizing radiation is provided by CT scans. CT uses X-rays to take many thin slices through the body, which are then reconstructed into cross-sectional images in axial, and can be viewed in coronal or sagittal planes. This combination of true slice-by-slice anatomy and the use of ionizing radiation is what sets CT apart from the other modalities. Radiography produces flat, 2D projections and does not give true cross-sectional slices. MRI creates cross-sectional images without ionizing radiation, using magnetic fields and radiofrequency. Ultrasound uses sound waves and also avoids ionizing radiation.

Cross-sectional imaging using ionizing radiation is provided by CT scans. CT uses X-rays to take many thin slices through the body, which are then reconstructed into cross-sectional images in axial, and can be viewed in coronal or sagittal planes. This combination of true slice-by-slice anatomy and the use of ionizing radiation is what sets CT apart from the other modalities.

Radiography produces flat, 2D projections and does not give true cross-sectional slices. MRI creates cross-sectional images without ionizing radiation, using magnetic fields and radiofrequency. Ultrasound uses sound waves and also avoids ionizing radiation.