Are nuclear medicine scans risky? Get the facts on radiation exposure, side effects, and when these tests should be avoided.
Nuclear medicine scans show what’s happening inside the body through small doses of radioactive tracers. These special materials (about the size of a grain of salt) help doctors spot problems like heart disease and cancer. While most tests don’t cause harm, patients might feel a bit odd or get itchy after the scan.
Doctors suggest pregnant women and kids skip these tests unless needed. The radiation dose from one scan equals about 6 months of natural background radiation from the sun and soil. Before any test, patients need to tell their doctor about allergies and ask questions about what to expect.
Key Takeaway
- Nuclear medicine uses a small amount of radiation, which can have risks.
- Errors can happen during these tests, leading to higher radiation exposure.
- Always talk to your doctor about any concerns before having a nuclear medicine test.
What is Nuclear Medicine?
Nuclear medicine scans offer a unique way to see inside the human body. These tests use small amounts of radioactive tracers (about 2-7 millisieverts) to create detailed images of organs at work.
Different types of nuclear scans serve different purposes:
- VQ scans check lung blood flow
- Bone scans detect unusual bone activity
- Thyroid scans examine gland function
The process starts when patients receive the tracer through injection, pill, or inhalation. A special gamma camera then captures the radiation signals, creating clear pictures of internal structures. The amount of radiation exposure stays lower than many CT scans.
Natural radiation exists everywhere in daily life, including common foods. A banana contains trace amounts from potassium-40. Medical professionals carefully control scan doses to ensure patient safety. The diagnostic benefits typically exceed any risks when checking for serious conditions.
Patients should discuss any concerns about radiation exposure with their healthcare provider before the procedure.
Risks from Radiation Exposure
Nuclear medicine tests use small amounts of radiation for organ and tissue imaging. Patients often worry when they see those words at medical centres, but understanding the facts helps reduce concern.
The radiation dose varies by test type. Most scans give between 1 and 20 millisieverts (mSv), with bone scans typically around 6 mSv. For comparison, people naturally get radiation from many sources – air travel, certain foods, and the ground itself.
Medical staff follow strict rules to keep radiation levels low. They use something called the effective dose principle, which means using just enough radiation to get clear pictures and no more. While some research points to small risks from multiple scans, a single test usually gives less radiation than what people get from natural sources in a year.
Patients should tell their doctors about past scans. Sometimes other options like ultrasound or MRI might work just as well without using radiation.
Maladministration Risks
Nuclear medicine errors need careful attention. These mistakes, called maladministrations, show up in roughly 6 out of 100,000 procedures (based on current medical data).
Common mistakes in nuclear medicine include(1):
• Incorrect dosage administration
• Wrong patient identification
• Improper injection technique
When doses aren’t right, patients face risks. Too much radiation might damage the thyroid, while too little won’t give proper scan results. Wrong patient mix-ups create unnecessary radiation exposure, and poor injection methods can make scans worthless.
Medical centres use safety protocols to prevent these issues:
• Multiple staff verification steps
• Regular staff training programs
• Incident reporting systems
While most errors don’t cause lasting harm, some can lead to organ damage or thyroid problems. Not all mistakes get reported – some slip through unnoticed or unreported. Patients should verify their details before procedures. Basic checks include confirming name, test type, and prescribed dose with medical staff.
Allergic Reactions
Radioactive tracer reactions happen in medical scans, though they’re not common(2). The body sometimes responds within minutes after the injection goes in. Signs start small – itchy patches on the skin, queasy stomach, or feeling a bit wobbly. These usually pass quickly (about 15-30 minutes). More noticeable reactions might bring raised red welts or make the heart beat faster than normal.
The really serious stuff, which affects about 1 in 10,000 patients, needs quick action:
- Breathing gets hard
- Blood pressure drops below 90/60
- Throat feels tight
Medical teams keep antihistamines and other emergency medicines ready (stored at 20-25°C). They check patients’ allergy history first, especially looking for past issues with iodine contrast or food allergies.
Before any scan using tracers, patients should mention:
- Previous allergic reactions
- Asthma history
- Current medications
- Food or medicine allergies
This helps doctors pick the safest approach for each scan.
Occupational Risks for Medical Staff
Nuclear medicine workers deal with radiation every day in Australian hospitals. These healthcare staff need proper protection from harmful rays while doing their jobs(3).
The average nuclear medicine worker gets less than 20 millisieverts (mSv) of radiation each year, which stays within safe limits. Still, even small amounts add up over time.
Safety gear includes:
- Lead aprons (blocks harmful rays)
- Dosimeter badges (tracks exposure levels)
- Protective screens
- Special handling tools
Long-term exposure might cause:
- Thyroid problems
- Skin changes
- Eye issues like cataracts
Hospital protocols require strict safety rules. Workers must check their equipment, maintain proper distance from radiation sources, and report any accidents right away. Regular monitoring helps catch problems early.
Nuclear medicine staff should track their exposure numbers carefully. Monthly badge readings show if safety measures work properly. Extra training helps workers stay up to date on the newest protection methods.
Public Misconceptions
Sources: ANSTO.
Nuclear medicine scans help doctors see inside the body. These scans use tiny amounts of radioactive tracers that show up on special cameras.
The radiation levels are quite small. Most nuclear medicine tests give off 3-20 millisieverts, about the same as getting a CT scan. That’s less radiation than many people get from natural sources in a year.
Here’s what happens during a scan:
- Patients get a small amount of tracer (through injection or drink)
- Special cameras track the tracer through the body
- Computers make detailed pictures of organs and tissues
The tracers don’t stay in the body long. Most break down within hours – fluorodeoxyglucose disappears in just 110 minutes. Australian hospitals follow strict rules about radiation safety, with regular checks by government inspectors.
Patients who feel nervous about these tests should talk with their doctors. Getting clear answers about radiation levels and safety measures makes the process less worrying.
FAQ
What is a VQ scan and how does it work?
A VQ scan, or ventilation-perfusion scan, is a type of imaging test that looks at how air and blood are moving through your lungs. It uses a small amount of radioactive material to track the flow of air and blood. This can help identify any issues with blood clots or other lung problems.
How does a lung scan work and what does it show?
A lung scan, also called a pulmonary ventilation/perfusion (V/Q) scan, uses small amounts of radioactive material to track the flow of air and blood in your lungs. It can show if there are any blockages or other issues that could be causing breathing problems. The scan creates images that allow your healthcare provider to closely examine your lung function.
What is a bone scan and how is it used in nuclear medicine?
A bone scan is an imaging test that uses small amounts of radioactive material to create pictures of the bones in your body. It can help identify areas of increased or decreased bone activity, which can indicate issues like fractures, infections, or cancer. Bone scans are commonly used to investigate unexplained bone pain or other bone-related problems.
What are the long-term effects of nuclear medicine procedures?
The long-term effects of nuclear medicine procedures are generally very low. The radioactive materials used are designed to be quickly eliminated from the body, and the amounts used are small. Most people do not experience any long-term side effects. However, there is a small increased lifetime risk of developing cancer due to radiation exposure. Your healthcare provider will carefully weigh the benefits and risks for your specific situation.
How do PET scans work and what do they show?
PET (positron emission tomography) scans use small amounts of radioactive materials called radiotracers to create detailed 3D images of the inside of the body. These images can show how organs and tissues are functioning, which can help diagnose and monitor various medical conditions. PET scans are particularly useful for detecting cancer, heart disease, and brain disorders.
How does blood flow imaging work in nuclear medicine?
Blood flow imaging in nuclear medicine uses radioactive tracers to track the movement of blood through the body. This can help identify areas with reduced or increased blood flow, which can indicate issues like blockages, injuries, or other circulatory problems. The radioactive material is injected into a vein, and then special cameras take images as it travels through the body.
What are gamma rays and how are they used in nuclear medicine?
Gamma rays are a type of high-energy radiation that is used in nuclear medicine procedures. Radioactive materials that emit gamma rays are injected into the body or inhaled, and special cameras then detect and create images of where the gamma rays are coming from. This allows healthcare providers to see how certain organs and tissues are functioning.
How do blood cell scans work in nuclear medicine?
Blood cell scans in nuclear medicine use small amounts of radioactive materials to track different types of blood cells, like white blood cells or platelets. This can help identify areas of infection, inflammation, or other issues related to the blood and immune system. The radioactive material attaches to the blood cells, allowing them to be detected by special cameras.
What is CT imaging and how does it differ from nuclear medicine?
CT (computed tomography) imaging uses X-rays to create detailed, cross-sectional images of the body. Unlike nuclear medicine tests that use radioactive tracers, CT scans do not require injecting or ingesting any radioactive materials. CT imaging is excellent for getting highly detailed pictures of bones, organs, and other structures, but it does not provide information about how those structures are functioning.
What are the key differences between short-term and long-term effects of nuclear medicine procedures?
The short-term effects of nuclear medicine procedures are generally minimal, with the main risk being a small amount of radiation exposure. This exposure is carefully monitored and kept as low as possible. The long-term effects focus more on the small increased lifetime risk of developing cancer due to radiation. However, the benefits of the information gained from these tests are usually considered to outweigh the small long-term risks.
How do nuclear medicine tests detect blood clots?
Nuclear medicine tests can use radioactive tracers to identify blood clots in the body. One common test is called a ventilation/perfusion (V/Q) scan, which looks at how air and blood are moving through the lungs. If a blood clot is present, it will show up as an area with reduced blood flow compared to normal lung tissue. This can help diagnose conditions like deep vein thrombosis or pulmonary embolism.
What are the potential side effects of nuclear medicine procedures?
The potential side effects of nuclear medicine procedures are generally very mild. The radioactive materials used are carefully designed to be quickly eliminated from the body, so the radiation exposure is minimal. The most common side effects may include slight discomfort from the injection site, temporary metallic taste, or mild nausea. Serious allergic reactions are extremely rare. Your healthcare provider will closely monitor you for any side effects during and after the procedure.
How do nuclear medicine tests affect the thyroid gland?
Some nuclear medicine tests, like thyroid scans and radioiodine treatments, specifically target the thyroid gland. The thyroid uses iodine, so radioactive iodine can be used to create images of the thyroid or treat thyroid conditions like cancer or an overactive thyroid. These procedures can temporarily affect thyroid hormone levels, so your healthcare provider will monitor your thyroid function before and after the test.
What precautions do patients need to take after a nuclear medicine procedure?
After a nuclear medicine procedure, patients are usually advised to take a few simple precautions. This may include avoiding close contact with pregnant women and young children for a short period, as the radioactive material could potentially be passed to others. Patients may also be advised to drink plenty of fluids to help flush the radioactive material out of their body more quickly. Your healthcare provider will give you specific instructions based on the type of procedure you had.
Conclusion
Nuclear medicine brings some risks that patients need to know about. Radiation exposure sits at the top of the list (though doses stay carefully controlled at 0.1-0.5 millisieverts per scan). Test errors can happen, and allergic reactions show up in about 1 in 10,000 cases. Doctors must explain these risks during consultation. While these procedures help diagnose and treat illness, patients should ask questions about safety measures and voice any concerns before their scan.
References
- https://www.mja.com.au/system/files/issues/200_01_200114/lar10145_fm.pdf
- https://mydr.com.au/tests-investigations/nuclear-medicine-and-radioactivity/
- https://www.arpansa.gov.au/understanding-radiation/sources-radiation/occupational-exposure/occupational-exposure-medical
