Nuclear medicine diagnoses
Nuclear medicine offers various diagnostic methods. Scintigraphies show the distribution of substances in the body. This distribution is documented pictorially. Scintigraphy is an essential part of diagnostics, especially for metabolic diseases. PET/CT, as a combination of computed tomography and positron emission tomography, is excellent for the early detection and evaluation of cancer.
PSMA PET/CT
Fast and accurate – Prostate cancers are not easy to diagnose on the one hand, and on the other hand, they are the most common type of cancer in men. PSMA PET/CT provides reliable information about the presence and stage of the tumor.
Where can you have a nuclear medicine examination in Munich?
Cancer detection and the diagnosis of metabolic diseases are among the core areas of our nuclear medicine at Radiologie München. Our team of specialists offers a wide range of services from scintigrams to sophisticated PET/CT for determining stages of carcinomas in the prostate or lungs. Just ask for an appointment.
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What is a scintigraphy?
Scintigraphy is when a small amount of a low-level radioactive substance(radiopharmaceuticals) is distributed in the body and this distribution is documented by imaging. The resulting image is called a scintigram. Scintigrams can be used to more accurately define and diagnose disease.
Direct administration or tracer use
There are different variants of the administration of the test substance. For example, in thyroid scintigraphy, radioactive iodine is administered directly. This then makes the processes in the thyroid gland optimally visible. At the same time, our specialists make sure that this examination is only performed if there are no concerns regarding the radiopharmaceutical used.
In addition to direct administration, the tracer method is also used. Tracer means carrier. These are certain proteins or salts to which the radioactive substance is bound. Since the tracer is only or to a large extent converted or better metabolized by certain organs, this process can then be excellently mapped.
Enrichment shows potential problem areas
After transfer to the metabolism, the radiopharmaceutical is deposited particularly well where metabolic activity and blood flow are especially high. The decay of the substance under examination can then be measured and transferred to an image by the irradiation with gamma rays that then begins.
Inflammation foci – and thus disease-causing areas – can thus be narrowed down and localized excellently. The body increases metabolism in these regions. Increased activity may indicate a tumor. With a subsequent biopsy, the diagnosis is then supported and further steps can be planned.
The use of scintigraphy is diverse, for example, bones, the thyroid gland or the heart muscle are often on the list of examinations.
PET/CT – an optimal combination
Tracers are also used in PET/CT. These radioactively labeled particles, which are contained in the examination fluid, are detected by a special PET/CT camera after they have been administered into the patient’s body. This also allows differences in blood flow to be detected and diseased tissue to be distinguished from healthy tissue.
Special measuring devices determine the radioactive radiation in the various cells of the body. The measurement data is forwarded to a computer, which compiles the information into a detailed picture. Due to the higher level of detail, the combination of PET and CT leads to results that can be assessed significantly better than the results from PET examinations alone. This is why nowadays hardly any pure PET examinations are performed, but almost only PET/CT examinations – this is also the case at our Radiologie München.
Radiopharmaceutical – lowest possible radiation exposure
The tracers used in scintigraphy and PET/CT are injected substances with very low levels of radioactivity. The load on the body is very weak. The substances used will be excreted by the organism within a very short time.
In rare cases, the tracers used may cause allergic reactions. These make themselves felt through nausea and vomiting. Sometimes itching, rash and shortness of breath also occur, severe circulatory problems are very rare. Intolerances will of course be asked about in the preliminary consultation and, if present, our medical team will look for an alternative solution together with your treating physicians.
The iodine-containing contrast medium that is injected directly for the examination, which has come under criticism in many places, can also lead to allergic reactions with symptoms similar to those just described. Here, too, we look for the most gentle variant for you.
Preparation for a nuclear medicine examination
Do you need to be sober?
Yes, you usually need to be fasting for a PET/CT scan. This means that you should not eat any more food before the examination. However, you may drink water, unsweetened tea and black coffee. After the examination, you should drink plenty of fluids and go to the toilet frequently to empty your bladder. In this way, you ensure that the tracer is quickly eliminated. It is also advisable to be fasting for a scintigraphy examination.
Can you continue to take your medications?
Before a planned examination, please discuss with your doctor whether you can take your medication as usual on the day of the nuclear medicine examination – especially if you are diabetic. Tell your doctor about all medications you are taking. Also inform him or her if you are currently receiving or have recently received chemotherapy or radiation.
How do the examinations proceed?
Nuclear medicine examinations vary widely in the duration of the examination. Times range from thyroid scintigraphy, which takes about 15 minutes, to bone scintigraphy, which takes about 3 hours. So you can expect approximately the following times in our rooms:
PET/CT has a slightly different timeline. Here it is usually always about 3 to 4 hours total duration. This is related to the time necessary for the distribution of the used examination substance in the body. Therefore, there is almost always this time sequence:
How high is the radiation exposure?
During scintigraphy, small amounts of radioactive substances are introduced into the organism. These so-called radiopharmaceuticals decay in the body within minutes to days. The substances are also quickly excreted by the body. Based on the data available on scintigraphy to date, there is no increased risk of late damage from scintigraphy.
How high the radiation exposure from scintigraphy is depends largely on the radiopharmaceutical used and the body region examined. The number of exposures does not matter because there is no additional radiation exposure. The radiation exposure during scintigraphy is very low and the risk of overlooking a disease or not treating it properly is usually much higher.
Nevertheless, the following applies: The examination cannot be carried out completely without radiation. Therefore, scintigraphy is not used as a routine examination for suspected cancer or for early detection of cancer, but only for specific questions. The same applies in principle to PET/CT. Despite the further reduction in radiation exposure in the meantime, this examination does not belong to the routine examinations.