What are the 2 examinations?

What are the 2 examinations?

• A. MRI and CT
• B. Ultrasound and X-ray
• C. SPECT and PET
• D. Angiography and DSA

Answer: (C)

Functional imaging of physiological processes using radiotracers is what these two examinations represent. Both SPECT and PET are nuclear medicine techniques that use injected or ingested radiopharmaceuticals to visualize metabolic activity and molecular pathways, not just anatomy. PET detects positron-emitting tracers and measures their metabolic or biochemical activity by capturing pairs of gamma photons produced during annihilation, yielding highly sensitive functional maps. SPECT uses gamma cameras to detect single-photon emissions from radiotracers, providing functional information such as blood flow, receptor activity, or metabolism, though with generally different resolution and physics from PET. These two stand apart from the others because MRI and CT primarily show anatomy and structural details, ultrasound and X-ray provide structural imaging with different technologies, and angiography/DSA focus on imaging blood vessels with contrast. The key idea is that SPECT and PET reveal how tissues are working at the molecular level, offering insights beyond what purely anatomical pictures show.

Functional imaging of physiological processes using radiotracers is what these two examinations represent. Both SPECT and PET are nuclear medicine techniques that use injected or ingested radiopharmaceuticals to visualize metabolic activity and molecular pathways, not just anatomy. PET detects positron-emitting tracers and measures their metabolic or biochemical activity by capturing pairs of gamma photons produced during annihilation, yielding highly sensitive functional maps. SPECT uses gamma cameras to detect single-photon emissions from radiotracers, providing functional information such as blood flow, receptor activity, or metabolism, though with generally different resolution and physics from PET.

These two stand apart from the others because MRI and CT primarily show anatomy and structural details, ultrasound and X-ray provide structural imaging with different technologies, and angiography/DSA focus on imaging blood vessels with contrast. The key idea is that SPECT and PET reveal how tissues are working at the molecular level, offering insights beyond what purely anatomical pictures show.