Dear Visitor,

You are referred you to our clinic for the diagnosis or therapy of your disease. Your health issue can range from a benign thyroid node, which needs the so-called thyroid scan, to a cancer disease which probably needs the most sophisticated diagnostic method in the field of medical imaging, namely Hybrid-Imaging via PET/CT-Scan, for the accurate staging. Since nuclear medicine is a steadily improving branch of the medical field, it needs some explanation in order to complete our examinations in the most convenient way. Here are some most frequently asked questions and answers:


What is nuclear medicine and how is a nuclear medicine examination performed?

Nuclear Medicine is a branch of medical imaging that uses tiny amounts of radioactive materials to diagnose and treat a variety of diseases, including various types of cancers, heart disease, gastrointestinal, endocrine and neurological disorders. Nuclear medicine patients are given a radioactive compound that travels through the body to the specific area being studied. Then the structure and function of the organ systems in the body are detected via a gamma camera in order to create the medical images, usually in 3-D, using computer systems.

Which radioactive compounds are used in the nuclear medicine?

Depending on the type of scan you have, you usually either swallow a small quantity of radionuclide, or it is injected into a vein in your arm. These compounds lose their radioactivity through the natural process of radioactive decay, and besides that, your body will lose some activity via urinary excretion. The most commonly used radioisotope for scintigraphy (of the thyroid, heart, lungs, bones, kidneys and parathyroid) is Tc-99m with a half-life of 6 hours. J-123 is used for neurological imaging (i.e. Datscan for Parkinson Disease). The most commonly used radiopharmaceutical for PET/CT-Scan is FDG (fluorodeoxyglucose) labeled with F-18. Furthermore, F-18 labeled PSMA is also a widely used, novel radiotracer for PET imaging of prostate cancer. An additional widely used radiopharmaceutical is DOTATOC labeled with Ga-68 which detects neuroendocrine tumors (NET) and paragangliomas.

I had already some treatments and tests in the past using radiation. Would it cause some harm to me?

We are all surrounded by radiation everyday with a great range of exposure depending on a lot of factors. In light of this, we can assure you that this additional radiation exposure through nuclear medicine examination is very little and therefore very unlikely to cause any harm to you, even if you had some radiological treatments in the past. Just for women of childbearing-age, a pregnancy has to be ruled out, because the radioactive substances also reach the unborn child via the maternal bloodstream. In the phase of organ development, especially in the first trimester of pregnancy, even a small dose of radiation exposure has to be avoided.

Do I need some special preparations for the examination? Should I worry about my children or my partner at home after the examination? Can I drive a car after examination?

Most of our exams do not require any preparation. However, for some types of scans you need to drink sufficient liquid to help to flush the radionuclide through your body, or for instance, in the case of renal scintigraphy, you will be asked to empty your bladder prior to scan. For heart stress scan you need to pause some medication (especially beta blockers and some other antihypertensive medication) 2 days before the examination.

The radionuclides decay naturally and to a little amount pass out of your body via urine, that is why only the pregnant and small children in your household should take some precautions for about 12 – 16 hours after the completion of scan. Since the radionuclides don’t influence the body metabolism or don’t act like drugs you don’t need to worry about your driving skills or other activities of high mental or physical concentration.

PET/CT imaging modality
Positron emission tomography (PET) is a specialized and most sophisticated nuclear medicine imaging technique that provides – with the combination of simultaneous low-dose-CT – high-resolution imaging and quantification of biologic changes using molecular imaging. This examination is mainly used for initial tumor diagnosis and therapy monitoring. In addition, it is also applied in the field of neurology and cardiology.

For the PET scan, a number of tracers can be used depending on the organ system and disorder to be examined. The most frequently performed scans in our department are FDG-PET/CT and PSMA-PET/CT. labeled with F-18.

- FDG-PET/CT
FDG is a glucose analogue, and its uptake by body or tumor cells reflects tissue glucose metabolism and It is usually high in high-grade tumors and relatively low in low-grade tumors. That is why FDG is the most commonly used PET tracer. The FDG is administered just like in most of other nuclear medicine procedures intravenously through a short tube connected to a needle in your arm. After a 1 hour waiting time, you will have to lie still on the scanner couch for up to 30 minutes while the scan is performed. In most cases, it is very well tolerated by our patients. They don’t feel any side effects during or after the scan. However, in some cases, you might get the IV contrast agent during the scan in order to increase the diagnostical (spatial) performance of the examination. During the whole procedure, you will be observed and instructed actively by one of our clinical staff.

After the completion of scan, you may continue all your normal activities, and you don’t need to worry about side effects or any other adverse effects. Since you have some radioactivity left in your body, you should keep a distance of 1 m from pregnant women and infants for 6 hours. Drinking plenty of fluids will help your body to clear the radioactivity more quickly.


For an optimal preparation for your FDG PET scan, please follow the instructions:

  • Do not have any food for 6 hours before your scan. Please drink plain unflavored water or other liquids but nothing else during this time. Please avoid smoking.
  • Avoid any strenuous exercise for 12 hours before your appointment.
  • If you are diabetic, it is also really important that your blood sugar at the tracer injection time is below 150 mg/dl. If you administer insulin, then the latest insulin has to be administered at least 4 hours in advance. If you need to inject the so-called long acting (basal) insulin such as Lantus or Levemir, then you may take it on the evening before the scan day (for the basal or long acting insulin please keep a time interval of 12 hours between insulin injection and scan time). For further questions regarding arrangements, please ask our staff. 
  • Since you might have iodinated IV contrast agent administered, we need your current laboratory values for kidney and thyroid function assessment (Creatinine and TSH, not older than 14 days) prior to the scan.

The results will be reported to the referring physician and/or discussed in our interdisciplinary tumor conference.

Arranging Appointments and Requests:
Tel +49 (0) 211-81-16318
Fax +49 (0) 211-81-17050
PET-Anmeldung@med.uni-duesseldorf.de

- F-18 PSMA-PET/CT
Prostate-specific membrane antigen (PSMA) is a transmembrane protein with significantly increased expression in the cells and metastases of prostate cancer correlating with tumor staging. The novel imaging modality of 18-F-labeled PSMA (PET/CT) exploits this characteristic feature of prostate cancer and proves to be a breakthrough improvement for its diagnostic and therapy monitoring.

For this examination:

  • You don’t need to do extra preparation or fasting.
  • You should bring up all the disease relevant medical records such as previous CT or nuclear medicine scan results, as well as operation and histopathological reports (the Gleason Score and the recent PSA values), if available.
  • Since you will probably have iodinated IV contrast agent administered, we need your current laboratory values for kidney and thyroid function assessment (Creatinine and TSH, not older than 14 days) prior to the scan.

The results will be reported to referring physician and/or discussed in our interdisciplinary tumor conference.

Arranging Appointments and Requests:
Tel +49 (0) 211-81-16318
Fax +49 (0) 211-81-17050
PET-Anmeldung@med.uni-duesseldorf.de

- Ga-68 DOTATOC-PET/CT

68Ga-DOTATOC PET/CT is an imaging modality in the workup of neuroendocrine tumors (NET), which shows high diagnostic sensitivity and is a strong predictor of successful somatostatin receptor directed treatments. The radiopharmaceutical (Ga-68 DOTATOC) is administered intravenously and the acquisition is performed after a waiting time of 60 minutes. 

For this examination:

  • You don’t need to do extra preparation or fasting.
  • You should bring up all the disease relevant medical records such as previous CT or nuclear medicine scan results, as well as operation and histopathological reports, if available.
  • If you are undergoing therapy with a somatostatin analogue (Somatuline, Sandostatin etc.), please contact us in advance by telephone, as it may be necessary to pause this medication.
  • Since you will probably have iodinated IV contrast agent administered, we need your current laboratory values for kidney and thyroid function assessment (Creatinine and TSH, not older than 14 days) prior to the scan.

The results will be reported to referring physician and/or discussed in our interdisciplinary tumor conference.

Arranging Appointments and Requests:
Tel +49 (0) 211-81-16318
Fax +49 (0) 211-81-17050
PET-Anmeldung@med.uni-duesseldorf.de

MediathekInformation und Wissen
LageplanSo finden Sie uns