9702 · 24.3
PET scanning
Welcome to the fascinating world of **PET scanning**! This advanced medical imaging technique, or **Positron Emission Tomography**, allows doctors to see inside your body not just structurally, but functionally. It helps pinpoint areas of **metabolic activity**, offering unique insights into how organs and tissues are working at a cellular level. This pilot aligns with **Senpai Corner** A Level notes (2025–2027) for topic **24.3**.
Need to know
What you need to know
- A **radiotracer** is injected into the patient. This is a biologically active molecule combined with a short-lived radioactive isotope that emits positrons (a positron-emitter).
- A very common tracer is **Fluorodeoxyglucose (FDG)**, which is an analogue of glucose. It contains the positron-emitter Fluorine-18.
- Cells with high metabolic rates, like cancer cells or active brain cells, consume large amounts of glucose. They readily absorb the FDG tracer.
- The Fluorine-18 nuclei within the FDG undergo **beta-plus (β⁺) decay**, emitting a positron.
Explanation
PET scanning
- A **radiotracer** is injected into the patient. This is a biologically active molecule combined with a short-lived radioactive isotope that emits positrons (a positron-emitter).
- A very common tracer is **Fluorodeoxyglucose (FDG)**, which is an analogue of glucose. It contains the positron-emitter Fluorine-18.
- Cells with high metabolic rates, like cancer cells or active brain cells, consume large amounts of glucose. They readily absorb the FDG tracer.
- The Fluorine-18 nuclei within the FDG undergo **beta-plus (β⁺) decay**, emitting a positron.