Functionality of PET

In positron emission tomography, good preparation and compliance with various measures are crucial for good image quality and informative value. Current blood values (especially kidney, thyroid and sugar values) must have been determined in advance. On the day before the examination, any physical exertion must be avoided.

In addition, no more food should be taken 12 hours before. Only water and unsweetened tea may be drunk during this period. Medications should be taken as usual, with the exception of those that strongly influence the blood sugar level.

The doctor treating you will give you recommendations for this. As with any imaging examination, it is also advisable to bring along any preliminary findings (CT, MRT, X-rays). Since the examination involves quite long waiting times, it is advisable to bring something to read. In some cases, the administration of a sedative may also be useful. In this case, if the PET examination is performed on an outpatient basis (not as part of an inpatient hospital stay), an accompanying person should also be brought along.

Procedure of the examination

For positron emission tomography, a vein access is required first. For this purpose, a small plastic cannula is usually placed and fixed in a vein in the crook of the arm. A small amount of radioactively marked glucose is injected through this access at the beginning of the examination.

A small amount of saline solution and a diuretic agent are then administered as an infusion (drip) via the vein access. Afterwards, it is necessary to wait about one hour so that the sugar can be distributed throughout the body via the blood system. It is very important that the patient sits as still as possible and avoids movement as far as possible.

Every movement leads to an accumulation of sugar due to muscle activity and can therefore influence the examination result. Patients who find it difficult to keep still due to nervousness or anxiety can be given a mild sedative. Then the actual examination begins with the PET scanner, which records the radiation emitted by the body.

Here too, the patient should lie comfortably and move as little as possible to prevent blurring of the images. The examination takes another 30 to 60 minutes. As long as no sedative has been administered, the patient is not affected in any way after the PET.