Nuclear Medicine

Nuclear medicine is a specialized branch of medicine that uses small amounts of radioactive materials for the diagnosis and treatment of various diseases. As a unique field within radiology, nuclear medicine focuses on visualizing how organs and tissues’ function, rather than just showing their structure. By tracking the behavior of radioactive tracers in the body, doctors can detect diseases at an early stage and monitor how well different organs are working. This makes nuclear medicine a valuable tool in identifying conditions that might not be visible with other imaging methods.

What is Nuclear Medicine?

Nuclear medicine is a unique medical specialty that differs significantly from conventional radiology methods like X-rays. While X-rays primarily produce images that show the body’s anatomical structure—such as bones or dense tissues—nuclear medicine focuses on organ function and the physiology of tissues. You can imagine it as “inside-out imaging,” since the information comes from within the body using specialized tracers.

A fundamental aspect of nuclear medicine is the use of a radioactive tracer, also called a radiopharmaceutical. These are compounds that contain a small, safe amount of radioactive material. A radiopharmaceutical is typically administered intravenously but can also be given orally or by inhalation, depending on the specific procedure. Once inside the body, the radioactive tracer travels to targeted organs, tissues, or areas where certain biological processes are occurring. The type of radiopharmaceutical chosen depends on which organ function or medical condition is being evaluated or diagnosed.

As the radioactive tracer accumulates in specific body parts, it emits tiny amounts of energy in the form of gamma rays. These emissions are detected externally by a gamma camera, which is a specialized imaging device. The gamma camera records the radiation pattern from inside the body, and a computer processes this data to produce detailed images. These images help doctors see how organs are working, evaluate blood flow, and detect abnormalities at an early stage that may not be visible through standard imaging.

Advanced nuclear medicine techniques like PET/SPECT (Positron Emission Tomography/Single Photon Emission Computed Tomography) enhance these principles, providing high-resolution, three-dimensional images that are crucial for early diagnosis, treatment planning, and monitoring the effectiveness of therapies. Nuclear medicine thus offers powerful, functional insights that go beyond what traditional anatomical scans can reveal.

Diagnosis and Treatment

Nuclear medicine offers a wide range of possibilities for both the early diagnosis and effective treatment of diseases. By using specialized radiopharmaceuticals to evaluate organ and tissue function, this field helps physicians detect conditions at an early stage and deliver targeted therapies. In recent years, the concept of theranostics has become increasingly important—this innovative approach combines diagnosis and treatment in a single, personalized procedure, allowing for tailored care that addresses each patient’s unique needs.

DIAGNOSIS: Imaging Services We Offer

Nuclear medicine provides a range of advanced imaging services that play a vital role in the early diagnosis of diseases. Through our imaging services, we can assess organ and tissue functions in detail, supporting accurate and timely diagnoses. In this section, we highlight key diagnostic scans such as PET/CT (Positron Emission Tomography/Computed Tomography) and SPECT (Single Photon Emission Computed Tomography). These state-of-the-art technologies go beyond traditional imaging methods by offering insight at the cellular level, which is essential for precise diagnosis and effective treatment planning.

PET/CT scans

PET/CT scans are among the most advanced imaging techniques in modern nuclear medicine. This method combines positron emission tomography (PET) with computed tomography (CT), providing detailed information about both anatomical structures and metabolic activity in the body. PET/CT scans play a vital role in cancer detection, as cancer cells tend to divide rapidly and consume more energy compared to normal cells. This increased energy demand corresponds to higher glucose utilization.

During a PET/CT scan, a patient is usually injected with a radioactive glucose molecule. This substance accumulates in the body’s most metabolically active regions, allowing doctors to visualize areas where cancer or other diseases may be present. The CT component helps accurately localize these metabolically active spots within specific anatomical areas. By merging both sets of images, physicians receive a comprehensive view that assists in determining the location, size, and possible spread of tumors. This integrated imaging approach is essential for proper staging and guiding the most effective treatment plans.

F18 FDG PET

F18 FDG PET is the most widely used agent in nuclear medicine PET imaging. It utilizes Fluorine-18 labeled fluorodeoxyglucose (FDG), which targets the elevated glucose metabolism of many cancer cells. F18 FDG PET is crucial for diagnosing, staging, and monitoring response to therapy across various cancer types, showing both the primary tumor and possible metastases with high sensitivity.

Ga68 PSMA PET

Ga68 PSMA PET is a highly specific imaging technique used primarily for prostate cancer. It targets the prostate-specific membrane antigen (PSMA), which is overexpressed on the surface of prostate cancer cells. Ga68 PSMA PET enables precise visualization of tumor sites and is highly accurate for assessing disease spread, recurrence, or treatment response.

Ga68 DOTA-TATE PET

Ga68 DOTA-TATE is considered the “gold standard” PET agent for diagnosing and staging neuroendocrine tumors (NET). It binds strongly to somatostatin receptors, which are commonly found on neuroendocrine tumor cells. Ga68 DOTA-TATE PET provides accurate information about the location, extent, and aggressiveness of NETs, supporting optimal disease management and follow-up.

Cardiac PET

Cardiac PET is a sophisticated heart scan method designed to assess heart muscle viability and blood flow. It accurately detects areas of the heart that have been damaged or receive poor blood supply, especially after a heart attack. By evaluating blood flow to the cardiac tissue, Cardiac PET helps determine the potential for recovery and guides decisions regarding interventions like bypass or stenting.

Brain Imaging (FDG, Amyloid)

Brain imaging with PET technologies plays a crucial role in diagnosing and monitoring neurological diseases. FDG PET examines brain metabolism, revealing changes associated with epilepsy, tumors, or various types of dementia. Amyloid PET specifically visualizes amyloid plaques linked to Alzheimer’s disease, allowing for early diagnosis and differentiation from other forms of dementia. This information is invaluable for treatment planning and ongoing management.

Scintigraphy and SPECT Imaging

Two fundamental techniques frequently used in nuclear medicine imaging are Scintigraphy and SPECT imaging. Scintigraphy displays the distribution of a radioactive substance in the body as two-dimensional (2D) images. This method allows for a quick assessment of the general structure and radioactivity uptake in organs and tissues. In contrast, SPECT imaging offers a more advanced approach; here, a gamma camera rotates around the patient at different angles, and the collected data is used to create three-dimensional (3D images) cross-sectional views. This provides more detailed information about the volume, depth, and location of the region being examined. SPECT imaging is particularly preferred for the precise detection of regional radioactive concentrations and for functional evaluation.

Thyroid Scan

A Thyroid scan is performed to evaluate the function and morphology of the thyroid gland. It examines the structure and function of thyroid nodules and provides information on conditions like hyperthyroidism, where the thyroid is overactive, as well as the functional characteristics of nodules.

Bone Scan

A Bone scan shows the metabolic activity of bone tissue throughout the body. It is frequently used for the early diagnosis of conditions such as metastatic bone disease, where cancer has spread to the bones, as well as for detecting hidden fractures, infections, and inflammatory changes.

Myocardial Perfusion Scan

A Myocardial perfusion scan is used to assess the amount of blood flow to the heart muscle and to evaluate potential blockages in the coronary arteries that supply the heart. By measuring the viability of the heart muscle under both rest and stress conditions, the presence and severity of coronary artery disease can be determined. This method is important for revealing heart attack risk and the functional status of the heart.

Kidney (Renal) Scan

A Renal scan is an imaging method used to evaluate the structure and function of the kidneys. It analyzes blood flow to the kidneys and overall kidney function and can detect blockages or other abnormalities in the urinary tract. This scan is also used to monitor the status of a transplanted kidney.

Lung Perfusion Scan

A Lung perfusion scan is used to visualize blood flow to the lungs. Especially when pulmonary embolism (a blood clot in the lung) is suspected, this scan can clearly show whether blood flow to the lungs is adequate and reveal any potential blockages in the vessels.

Brain (DatScan) Scan

A DatScan is a scan performed with a special radioactive substance to visualize dopamine transporters in the brain. It is particularly useful in distinguishing Parkinson’s disease and similar movement disorders, providing important information for diagnosing diseases that affect the dopamine system.

Parathyroid Scan, Dacryoscintigraphy, Lymphoscintigraphy

A Parathyroid Scan is performed to detect parathyroid adenomas and the overproduction of hormones by the gland. Dacryoscintigraphy is used for diagnostic purposes to visualize blockages and flow disorders in the tear ducts. Lymphoscintigraphy is used to map the flow of the lymphatic system, especially for identifying lymphedema and locating lymph nodes before a biopsy.

The Procedure: What to Expect

The procedure in nuclear medicine imaging serves as a guide for patients throughout the diagnostic process. This process includes pre-preparation, imaging, and result evaluation stages. In this section, we aim to inform patients about what to expect by explaining the general steps of a diagnostic scan. Each step directly affects both the quality of the images and the accuracy of the diagnosis.

Preparation

Careful preparation is required before every nuclear medicine scan. Preparations vary depending on the type of scan and the targeted organ. For many scans, a period of fasting may be necessary; this is important to ensure the radioactive substance distributes correctly in the body and to prevent inaccurate results. Additionally, you may be asked to temporarily stop or change the dosage of certain medications. All this preparation information is usually communicated to patients in detail before their appointment and plays a critical role in achieving the most reliable results.

On the scan day: Injection and Imaging

On the day of the scan, the process typically begins with the injection of the radioactive drug into a vein. Following the injection, a waiting period is necessary for the drug to accumulate in the target organ or tissue. This waiting period is known as the uptake time and can vary depending on the radiopharmaceutical used, ranging from a few minutes to several hours. Once the uptake time is complete, the actual imaging phase begins. During this phase, the patient usually lies still on a table while images are taken with special cameras. Remaining motionless is crucial for the clarity and accuracy of the images.

Your Results

The images obtained from the scan are carefully reviewed by an experienced nuclear medicine physician. The specialist analyzes the images and compiles the relevant findings into a detailed report. These results are then shared with the patient’s referring doctor, and the treatment plan is created based on this information. This process forms the foundation of a precise and reliable diagnosis.

THERAPY: Treatment with Nuclear Medicine

Nuclear medicine is a medical branch that offers significant opportunities not only in diagnosis but also in treatment. The therapies applied in this field provide targeted approaches, especially for diseases like cancer. Radionuclide therapy is based on delivering radioactive substances directly to cancerous cells or diseased tissues. This way, the radioactive drug affects only the problematic area, causing minimal damage to surrounding healthy tissues. This selectivity minimizes unwanted side effects while increasing treatment effectiveness.

Today, the concept of theranostics is an innovative approach in nuclear medicine that combines both diagnosis and treatment. In this method, the diseased area is first identified by imaging with a special molecule, and then direct treatment is provided with the same or a similarly structured radioactive substance. Thus, the treatment is customized according to the patient’s biological characteristics. This precise and personalized aspect of nuclear medicine treatments helps preserve patients’ quality of life while significantly increasing treatment success.

Commonly Diagnosed Conditions

Nuclear medicine plays a significant role in the diagnosis and treatment of various diseases through the precise use of radioactive substances. This section provides summaries of some common diseases and their treatment mechanisms in nuclear medicine. The treatments are based on radioactive substances targeting diseased cells or specific biological pathways directly. This method allows for intensive treatment of the active disease area without harming healthy tissues.

Hyperthyroidism

Hyperthyroidism is a condition where the thyroid gland is overactive, producing more hormones than normal. For treatment, radioactive iodine (I-131) is given orally, targeting the overactive cells in the thyroid gland. The radioactive iodine is absorbed by these cells, stopping their function, and allowing the gland to return to normal hormone levels. This offers an alternative to surgery or continuous medication.

Thyroid Cancer

In the treatment of thyroid cancer, radioactive iodine is administered to target any remaining thyroid tissue after surgery or cancer cells that have spread throughout the body. Both healthy and cancerous thyroid cells have the ability to absorb iodine. This allows the radioactive iodine to reach and destroy cancer cells, reducing the risk of recurrence and increasing the chances of recovery.

Prostate Cancer

In the treatment of advanced prostate cancer, radioligand therapies such as Lu-177 PSMA are prominent. This treatment involves administering radioactive molecules that target the PSMA (Prostate-Specific Membrane Antigen) protein on the surface of prostate cancer cells. The radioactive ligand delivers a high dose of radiation to the cancer cell, helping to shrink or destroy the tumor. This method offers promising results for patients who do not respond to standard treatments.

Pancreatic Cancer

In the treatment of pancreatic cancer, targeted radionuclide therapies are being investigated. These treatments use radiopharmaceuticals designed to bind to specific receptors on cancer cells, delivering radiation directly to the tumor while minimizing damage to surrounding healthy tissue.

Neuroendocrine Tumor

A special method called PRRT (Peptide Receptor Radionuclide Therapy) is used for the treatment of neuroendocrine tumors. The treatment involves administering radioactive peptides that bind to somatostatin receptors on the surface of tumor cells. The radioactive substance reaches the tumor directly, stopping or causing the regression of cell growth and proliferation. It is particularly effective in widespread or advanced tumors.

Metastatic Liver Disease

For metastatic liver disease, a treatment known as transarterial radioembolization (like Y-90) is used. This involves injecting microscopic radioactive spheres into the liver’s arteries, which then travel to and lodge within the tumors, delivering a high dose of localized radiation.

Metastatic Bone Disease

Nuclear medicine offers palliative treatment for metastatic bone disease. Radiopharmaceuticals such as Strontium-89, Samarium-153, or Radium-223 are administered, which are absorbed by areas of high bone turnover, like metastases. They emit radiation that destroys cancer cells, helping to reduce bone pain and improve quality of life.

Pheocromocytoma

Pheocromocytoma, a type of neuroendocrine tumor, can be treated with I-131 MIBG therapy. The MIBG compound is selectively absorbed by these tumor cells. The attached radioactive Iodine-131 then delivers targeted radiation, helping to shrink or destroy the tumor.

Commonly Used Theranostic Radiopharmaceuticals

Theranostic radiopharmaceuticals used in nuclear medicine are innovative agents that simultaneously perform diagnosis and treatment in a targeted manner. These special substances bind to a specific molecular target, serving both imaging and therapeutic functions. This allows treatments to be planned specifically for the patient’s biology, effectively treating diseased tissue while preserving healthy tissue. These radiopharmaceuticals, which have led to significant advances, especially in cancer treatment, aim to improve patient quality of life by combining diagnosis and therapy.

I-131

I-131 is a classic theranostic agent widely used in the treatment of thyroid cancer and hyperthyroidism. Thyroid cells naturally absorb iodine, making radioactive iodine useful for both diagnostic imaging and the destruction of diseased cells. It is particularly important for eliminating remaining cancer cells after thyroid surgery and treating functional disorders.

177Lu-PSMA

177Lu-PSMA is a theranostic agent used in the treatment of prostate cancer. This molecule binds to the PSMA (Prostate-Specific Membrane Antigen) protein on the surface of prostate cancer cells and delivers targeted radiation to destroy the tumor cells. This allows a high dose of radiation to be delivered to the cancer cells while protecting surrounding healthy tissues as much as possible.

177Lu-DOTA-TATE

177Lu-DOTA-TATE is a radiopharmaceutical particularly preferred for the treatment of neuroendocrine tumors. It selectively binds to somatostatin receptors on the surface of tumor cells and directly targets these cells with the applied radiation. This treatment offers effective results in widespread or treatment-resistant neuroendocrine tumors.

Y-90 Transarterial Radioembolization

This is a targeted therapy primarily for liver tumors. Microscopic spheres containing the radioisotope Yttrium-90 are injected into the arteries supplying the liver. These spheres become trapped in the small vessels of the tumors, delivering a high dose of localized radiation directly to the cancerous tissue.

P32

Phosphorus-32 (P32) is a radiopharmaceutical used in therapy for certain blood disorders, such as polycythemia vera, to suppress the overproduction of red blood cells. It is also used for palliative care to relieve pain from bone metastases.

I-131 MIBG

I-131 MIBG is a theranostic agent used for both imaging and treating specific neuroendocrine tumors, such as pheochromocytoma and neuroblastoma. MIBG is taken up by these tumor cells, allowing the attached Iodine-131 to deliver targeted, destructive radiation.

The Procedure: What to Expect

Undergoing nuclear medicine treatment involves a series of structured steps designed to ensure patient comfort, safety, and the best possible results. Each stage, from the initial meeting to follow-up, focuses on providing clear guidance and support.

Consultation and eligibility

The process typically begins with a thorough consultation with a nuclear medicine specialist. During this visit, your overall health, medical history, and diagnosis are closely reviewed. The doctor evaluates your suitability for the proposed treatment and answers any questions you may have. This stage is essential for creating an individualized care plan tailored to your needs.

Preparations before therapy

Once treatment is planned, you will receive detailed instructions about necessary preparations. Depending on the type of therapy, you may need to follow specific dietary restrictions, adjust your hydration, or temporarily stop certain medications. For example, before thyroid treatments, you might be advised to avoid iodine-rich foods and supplements. These preparations help maximize the safety and effectiveness of the treatment.

On the treatment day

On your treatment day, you usually come to the clinic in the morning. Most nuclear medicine therapies are outpatient procedures, meaning you can go home the same day. The radioactive medicine is administered—most often by injection or sometimes orally—by the medical team. Afterward, you may be monitored for a short time to observe any immediate reactions and ensure your comfort.

Your Follow-up

After treatment, regular follow-up appointments are scheduled to monitor how well the therapy is working and how you’re feeling. These visits may include blood tests, imaging scans, or other assessments to track your recovery and address any side effects. Ongoing follow-up is key to optimizing your long-term health and adjusting your care plan as needed.

By understanding each step—from consultation and preparation to treatment day and follow-up—you can feel more confident and prepared throughout your nuclear medicine treatment journey.

Safety and Patient Instructions

In nuclear medicine procedures, patient safety is always our highest priority. Throughout every step, the radiation dose is kept as low as possible while maintaining diagnostic or therapeutic effectiveness, following strict international safety standards. We understand that many patients have concerns about radiation exposure, and our team is committed to transparent communication and education to help address any fears. Before and during your procedure, you will receive detailed instructions and information about the safety measures in place. All equipment is regularly calibrated, and only trained, experienced professionals carry out the procedures. By maintaining these rigorous safety protocols, we ensure your treatment is both effective and comfortable, giving you peace of mind during your care.

Radiation Dose

Radiation dose is a key consideration in all nuclear medicine procedures, and patient safety is always the highest priority. In diagnostic tests, the amount of radiation administered is very low—typically comparable to that of a standard computed tomography (CT) scan. To further protect patients, every procedure is planned and carried out according to the ALARA principle (As Low As Reasonably Achievable). This internationally recognized guideline ensures that the radiation dose is kept to the minimum necessary for accurate diagnosis, without compromising image quality or patient care. By strictly adhering to the ALARA principle, we are able to provide both effective and safe diagnostic and therapeutic services, giving patients confidence and peace of mind throughout their care.

Pregnancy and Breastfeeding

Before undergoing any nuclear medicine procedure, it is essential to inform your doctor if you are pregnant or suspect a pregnancy. Since radioactive materials are used, this information is crucial to ensure the safety of both you and your baby. Your physician will carefully evaluate the risks and benefits to decide on the most appropriate approach.

If you are breastfeeding, you may need to temporarily stop nursing after the procedure, depending on the type of radioactive substance used. The healthcare team will provide detailed instructions on how long to pause breastfeeding and how to manage breast milk during this period. Always consult your doctor for specific guidance to protect both your health and your child’s well-being.

Post-Procedure Care

After a nuclear medicine procedure, it is important to follow some simple instructions for proper and effective post-procedure care. One of the most important recommendations is to drink plenty of water. This helps the radioactive substance administered to your body to be quickly eliminated through the kidneys. Increasing fluid intake shortens the time the radioactive material stays in the body, helping to reduce radiation exposure and protect your overall health. Additionally, you must adhere to any specific advice and potential restrictions given by your healthcare team. These simple measures will help you have a more comfortable and safe post-procedure period.

Pediatric Patients

Nuclear medicine applications can also be safely performed for children when necessary. Especially when it comes to pediatric patients, the doses of radiopharmaceuticals used are precisely adjusted according to the child’s age, weight, and clinical needs. Thanks to these personalized dose adjustments, the lowest possible radiation exposure is ensured while maintaining the effectiveness of the diagnosis or treatment. Furthermore, the child’s safety and comfort are prioritized during the procedure; the entire team works diligently to ensure the child goes through the process comfortably and safely. Thus, nuclear medicine methods can be used as an effective and reliable option for pediatric patients as well.