What is FDG in PET Scan?, How FDG Works:, FDG Injection Protocol (Step-by-Step)

🧪 What is FDG in PET Scan?

FDG stands for Fluorodeoxyglucose, a radioactive glucose analog used as a radiotracer in PET scans. It helps detect areas of high metabolic activity such as:

• Cancer cells

• Inflammation

• Infection

• Active brain or heart tissues

🔬 How FDG Works:

• FDG behaves like glucose and is taken up by metabolically active cells.

• These cells use more glucose, so they accumulate more FDG.

• The PET scanner detects the radioactive signals from FDG and creates images.

💉 FDG Injection Protocol (Step-by-Step)

1. Patient Preparation:

Step	Notes
Fasting	6–8 hours fasting (water allowed)
Blood Glucose	Should be <150 mg/dL for best results
Check Allergies	Rare, but important if contrast CT is used
Rest Period	Patient should rest for 20–30 minutes before and after injection to reduce muscle uptake

2. FDG Dose:

• Adult Dose: Typically 5–15 mCi (185–555 MBq) depending on body weight

• Route: Intravenous (IV)

3. Injection Process:

1. Ensure proper IV access (usually peripheral vein)

2. Inject FDG slowly over 30–60 seconds

3. Flush with 10 mL normal saline after injection

4. Instruct the patient to lie still and relax in a quiet room for 45–60 minutes uptake time

4. Safety Precautions:

• Use lead-shielded syringe

• Wear protective gloves

• Use TLC wipes and follow radiation hygiene protocols

• Dispose of radioactive waste in designated bins

FDG SIDE EFFECT