I had my third PET/CT yesterday. Last one was in August 06. Instructions were:

No food for 8 hours prior to scan. Drink water, but no other type of liquid

Restrict carbohydrates for 24 hours. That means NO carbs or sugar.

You are injected with a radioactive glucose about an hour prior to the PET. The idea is that cancer cells are 'hypermetabolic'; they use glucose (sugar) faster than other cells and will 'light up'.

Hope that helps.

dx 2/13/06. modified radical neck dissection 3/9/06 multiple biopsies of upper airway and direct laryngoscopy. 1 of 47 lymph nodes positive for metastatic undifferentiated carcinoma (lymphoepithelioma). Unknown primary. Finished radiation 5/24/06.