Manchester

At the Manchester site, the two other scanning methods do have some associated risk. They are:

Glucose MRS

The glucose MRS scan will take place in the same MRI scanner at the MRS scan. Therefore the check for metal objects will also cover this scan. The glucose is given as an intravenous (‘drip’) infusion of glucose during the scan through a cannula (small plastic tube) inserted into a vein in your arm, hand or foot. You might experience brief discomfort with the cannulation. It is a safe procedure however, and something you may have experienced if you have stayed in hospital. There is a small risk of developing a condition called ‘thrombophlebitis’ at the site of a cannula, which means local inflammation and clotting of blood within a vein. Rarely this can lead to complications but most cases get better on their own. The risk of this is very low given the short amount of time the cannula will remain in the vein.

This scan causes a mild increase in the level of glucose (sugar) in the blood. This could in theory trigger abnormal heart rhythms in people with certain rare heart conditions so we will check your ECG and blood pressure.

PET

The scan involves injecting a radioactive marker through a cannula (small plastic tube) in the vein. The same risks regarding the cannula would apply as for the Glucose MRS scan above. As this is a radioactive marker, you will receive a small dose of radioactivity as part of this study. We are all exposed to what is known as background radioactivity every day, mostly from natural sources of radiation in the earth. Low doses of radiation give us a small risk of developing cancer. However, risk comparisons show that radiation is a small risk when compared to the natural incidence of cancer (the number of people who would go on to develop cancer anyway), every day risks people take such as driving, and lifestyle factors such as smoking and alcohol consumption. Participating in this study will very slightly increase your chances of cancer death over your lifetime.

However, this extra risk is very small (approximately 2 in 10,000). The total radiation exposure you will receive in this study is equivalent to one and a half years average background radiation in the UK, or the radiation you would receive from a single CT (computed tomography) scan of the head.

This research study has been approved by ARSAC (Administration of Radioactive Substances Advisory Committee) which reviews all UK medical research involving the administration of radiation to humans.  The radioactive drug is given in an extremely low dose and no side effects are expected. For individuals who have received this drug in the past, no side effects have been observed. There will be no residual radiation once the scan is completed.

See also: Confidentiality of your data