Nuclear Medicine Exams
A patient guide to Nuclear Medicine Exams at Radiology Associates.
What is nuclear medicine?
Nuclear medicine uses tiny, safe amounts of radioactive material — called a radiotracer — that travels through your body to specific organs or tissues. A special camera (a gamma camera) detects where the tracer collects and creates images that show how organs are working, not just what they look like. This functional information complements the anatomic detail of CT and MRI.
What it's used for
- Bone scan for cancer spread, fractures, and infection
- Thyroid scan and radioiodine therapy
- Cardiac stress test evaluating blood flow to the heart muscle
- Kidney function studies (renal scans)
- HIDA scan evaluating gallbladder function
- Gastric emptying studies
- Lung scan looking for blood clots
- Tumor-specific scans: DOTATATE for neuroendocrine tumors, PSMA for prostate cancer
How to prepare
Preparation varies considerably by exam — we'll give you specific instructions when your exam is scheduled. You may be asked to:
- Stop certain medications for a period of time
- Fast for several hours
- Drink water and arrive well-hydrated
- Hold or adjust diabetes medications
Tell us about any allergies, recent contrast or radiotracer studies, and whether you're pregnant or breastfeeding.
What to expect during your exam
The radiotracer is given as an IV injection, oral capsule, or inhaled gas, depending on the exam. Some exams image immediately; others require waiting hours or even days for the tracer to settle in the right place. We'll explain the timing in advance.
When it's time to image, you'll lie still on a padded table while a gamma camera moves slowly around you. Imaging time varies from 20 minutes to over an hour. Most exams are painless — the IV is the only minor discomfort.
Is it safe?
The radiation dose from most nuclear medicine exams is comparable to a CT scan. The radiotracers break down quickly and are gone from your body within hours to a few days.
Pregnant or breastfeeding patients should always notify us beforehand — we may need to adjust timing or choose another approach.
After your exam
Drink extra fluids to help your body clear the tracer. For most exams, you can resume normal activities right away.
For certain therapeutic doses (such as radioiodine for thyroid disease), specific precautions are required to limit close contact with others for a short period. Your physician will explain these in detail and provide a written plan.