SPECT produces images similar to

• A. Ultrasound
• B. CT or MRI
• C. X-ray
• D. PET

Answer: (B)

The main idea is that SPECT is a functional imaging method, showing how a radiotracer is distributed and behaving in the body, rather than just how tissues are structured. Because it visualizes metabolic or molecular activity with tracer uptake, SPECT images resemble PET images in both purpose and appearance: bright regions indicate higher activity, and the data are displayed as cross‑sectional slices that reveal function.

In contrast, CT and MRI focus on anatomy—bone anatomy, soft tissue contrast, or other structural details—rather than tracer-based function. Ultrasound and X-ray likewise emphasize anatomy and density differences rather than metabolic processes. That’s why the functional information from SPECT aligns more closely with PET, even though many SPECT studies are combined with CT to give precise anatomical localization.