PET = Positron Emission Tomograph and
CT = Computer Tomograph
The combination of a PET-scanner and a CT enables quick imaging diagnostics with high resolution and an optional 3D-representation, shows metabolic processes of the body and is predominantly being used for oncological diagnostics but also in the context of cerebral diagnostics (clarification regarding epilepsy or dementia) and for single cardiological cases.
An examination of the entire body may take between 20 and 30 minutes, cerebral examinations take 15-20 minutes. The examinations may also be performed in total anesthesia which is a decisive advantage e.g. as concerns examinations of children.
The PET-CT images allow – by means of a special software- also a fusion resp. overlapping with images of other examinations, e.g. of MRI (magnetic resonance imaging) examinations, even if these have been performed by other institutions.
The radiation dose
The PET examination requires just a small amount of very short-lived radioactive substances whose half-life amounts to only a few minutes to approx. 2 hours. These substances decay within a very short period of time and do not cause side effects on the human body due to their very low dose. Consequential physical damages in the context of the low amount of applied radioactivity have not yet been reported also after decades of experience regarding the examination-substances. Approx. two thirds of the exposure to radiation during a PET-CT examination are being caused by the X-ray radiation of the conventional CT-device and include different intensities depending on the accordant required examination-technique. The radiation dose of the PET-CT-examination lies within the so-called diagnostic range and is justifiable from the medical point of view against the background of the relevant item.
The examination should however be avoided in case of pregnancy. You must therefore inform the physician if you are pregnant or even if you think that you are pregnant. A pregnancy test can, as the circumstances may require, also be performed at short notice.