• Whole Body PET-CT examination
• Brain PET-CT examinations

Metabolic Imaging: Positron Emission Tomography (PET)

PET is a diagnostic procedure with several decades of history, enabling rapid, accurate, and safe examination of most malignant tumors and inflammatory diseases. The PET scanner creates images of the functioning of the body’s tissues and organs, thus essentially mapping pathological processes occurring within the human body. PET diagnostics are primarily used for the early detection of malignant tumors, for assessing disease severity, and for evaluating the effectiveness of treatments. PET imaging significantly improves diagnostic accuracy, which can lead to changes in the treatment plan for more than one-third of patients.

The Essence of PET/CT Imaging

The most advanced PET diagnostic devices now integrate both PET and CT scanners into a single combined imaging system, known as PET/CT. By combining the advantageous properties of each component, PET/CT systems provide both anatomical and functional information about the patient in a single examination.

For a PET scan, the patient receives a small amount of a radiolabeled substance (most commonly a glucose molecule—18F-FDG) via intravenous injection. The distribution of this tracer within the body—depending on the metabolic activity of the cells—is then visualized using the PET scanner.

CT is a radiological imaging method that creates images of organs based on the different absorption of external X-rays by various tissues.

The PET examination is completely painless. The optimal amount of radiopharmaceutical required for PET imaging is administered individually based on body mass index (BMI) calculation. When using 250 MBq of 18F-FDG, the effective dose is approximately 4–7 mSv. According to the scientific literature, no allergic reactions to this tracer have been reported. The preceding low-dose native CT scan (performed without intravenous contrast agent) contributes an additional radiation exposure of about 2–6 mSv.

• Bone and Joint Scintigraphy

• Liver and Biliary Tract Examination

• Lymph Node and Lymphatic Scintigraphy

• Thyroid Scintigraphy

• Myocardial Scintigraphy

• Ventilation-Perfusion Lung Scintigraphy

• Renal Scintigraphy

Radiopharmaceutical Imaging Procedures

During nuclear medicine examinations, the radiolabeled substance is most commonly administered intravenously (in some cases orally or via inhalation). Depending on the type of examination, a compound is selected that either accumulates in or is excreted by the target organ. Based on the physiological function of the organ, a waiting period may be required after injection before the images can be taken. In some cases, imaging may only be performed several days after administration.

The duration of the imaging varies: some tests are shorter, others take longer. During longer procedures, parents or caregivers may stay with children or debilitated patients throughout the entire process.

Preparations on the Day of the Examination

Examinations are performed by appointment only. Due to the radioactive material’s decay, it is crucial that patients arrive on time—if late, the test may not be carried out.

Upon arrival, patients should bring:

• Their referral form

• Personal identification

• Health insurance card

• Previous medical records and discharge summaries

To avoid unnecessary radiation exposure, we kindly ask patients not to bring children into the laboratory unless the child is the one being examined.

Most examinations do not require any special preparation. Patients may eat and take their medications as usual.

Examinations Requiring Special Preparation

• Liver and biliary tract scan – must be performed in a fasting state.

• Bone scan – patients should bring 1 liter of fluid to drink.

• Lung scan – patients must bring their most recent chest X-ray image.

• Kidney scan – it is important that patients drink plenty of fluids beforehand.

Examination Risks

The diagnostic and therapeutic use of radiation has been well established in medical practice for decades. The radiation exposure from these examinations is low, comparable to that of standard X-ray tests. It corresponds to about 6–18 months of natural background radiation (from cosmic and environmental sources) for an average person. The dose received is about 5–10% of the maximum annual dose considered safe for medical professionals working with radioactive materials. After the scan, patients can safely use public restrooms and be in public spaces without posing any significant risk to others.

If patients have questions or concerns, they are encouraged to speak with our nuclear medicine specialists.

Side Effects

The radioactive material administered does not typically cause any side effects. Allergic reactions are extremely rare.

After the Examination

Patients may eat and drink as usual after the test. However, they should avoid contact with pregnant women and children under 16 years of age for the rest of the day.

Results

The results will be sent to the referring physician or to the patient by post within three working days. Upon request, patients may also discuss their results with a nuclear medicine specialist.

For Female Patients

Isotopic examinations are not recommended if the patient is pregnant or suspects pregnancy. Please inform our staff before the examination if you are pregnant or breastfeeding. If the referring physician considers the test necessary despite this, it may still be performed—it is not strictly contraindicated.

• MIBG Scan with Iodine-123/Iodine-131 Isotope

• Tc-99m Tektrotyd Scintigraphy

SPECT Examination – A Method of Nuclear Medicine

SPECT (Single Photon Emission Computed Tomography) is a nuclear medicine imaging technique. During the examination, a radiopharmaceutical (a substance containing a radioactive isotope) is administered to the patient. By detecting the emitted radiation, we obtain information about the function of the organs being examined.

CT (Computed Tomography) is a radiological imaging method in which X-rays pass through the patient’s body, and based on the varying absorption of radiation by different tissues, it provides anatomical details of the organs’ shape and structure.

By combining the two techniques, we can take advantage of both their strengths—obtaining both anatomical and functional information about the organs in a single examination.

Why Is SPECT/CT Better Than Separately Performed SPECT and CT?

When performing a SPECT/CT scan, the images are taken sequentially while the patient remains in the same position, which ensures perfect spatial alignment. In contrast, when the scans are performed separately, significant image processing is required to align the SPECT and CT images, and even then, alignment may not be accurate.

The combined (fused) imaging allows for more precise localization of abnormalities that show increased radiotracer uptake.

CT only visualizes changes that cause structural alterations in an organ, while SPECT detects functional abnormalities, which may occur before structural changes are present—allowing for earlier detection of disease.

The patient also benefits by not needing two separate appointments, saving both time and travel costs.

Common Applications of SPECT/CT

• Bone Abnormalities: Bone scintigraphy detects areas of altered bone metabolism. CT provides the structural view of those areas, allowing clinicians to distinguish between tumor metastases, old fractures, or degenerative changes.

• Oncology: Helps precisely define the extent of a tumor, its spread to surrounding tissues, and the location of metastases. In known cancer patients, functional changes detected by SPECT can reveal new metastases earlier than structural imaging alone.

Clinical Indications for SPECT/CT Scans

SPECT/CT is used in the following types of full-body or focused scans:

• Whole-body imaging with radiopharmaceuticals such as MIBI, Gallium citrate, LeucoScan, I-131, Thallium chloride (TlCl), Indium-Octreotide, I-123 or Tc-99m Tektrotyd, I-131 MIBG

• Joint scintigraphy (whole-body)

• Parathyroid imaging

• Pulmonary scintigraphy

• Bone scintigraphy (when abnormal focal uptake is seen on whole-body images)

• Other SPECT scans, e.g., for evaluating focal liver lesions