The specialized radiology technique, nuclear medicine, uses a gamma camera to create images of blood flowing and organs functioning in a patient’s body. It’s an exciting science because there are nuclear medicine studies for imaging virtually every major organ system. And, this technology is diagnosing cancer and other life-threatening diseases in their earliest stages, when treatments offer the most benefit.
The imaging procedure at Yuma Regional Medical Center usually begins with a nuclear medicine technologist administering an injection. The injected fluid contains tracers, which are very low-dose radioactive material. A scanner then detects the tracers’ radiation and transforms that energy into images. The radiation a patient is exposed to during a nuclear medicine test is very low and does not cause harm or damage.
To provide an example, an oncologist can assess the presence and spread of cancer in a patient’s bones by first injecting a liquid pharmaceutical containing technetium into the patient’s blood stream. The tracers in the technetium travel through the bloodstream to reach the bones. Over approximately three hours, the radioactive tracers accumulate in the bones. A technologist then uses a gamma camera to take images of the bones. If abnormal bone function is present, the trouble spots will illuminate on the scan. Hours after the procedure, most of the tracer has dissipated from the body. In the case of technetium, approximately 75% of the radiation leaves the body within 12 hours. It is virtually undetectable after two days.
Doctors frequently use nuclear medicine procedures to:
- Identify internal bleeding
- Detect and measure dysfunctions in the thyroid, lymph nodes, stomach, gall bladder, intestines, kidneys and urinary tract
- Evaluate blood flow in kidneys, lungs, brain, and liver
- Identify tumors
- Judge the aggressiveness of tumors
- Investigate neurological disorders and brain abnormalities
- Evaluate bone cancers and other skeletal diseases
For digestive scans, patients at YRMC usually swallow a hard-boiled egg that contains the radioactive tracers. Patients having lung and respiratory scans often inhale the tracers in an aerosol form.
How Nuclear Medicine Compares to X-ray and CT Scans
Nuclear medicine, x-ray, and CT scanning all create images using radiation. CT scanners and x-ray machines beam radiation through
a patient. In contrast, nuclear imaging puts radiation inside the patient and captures images of the radiation broadcasting out of
the patient. Contrary to popular belief, x-rays, CT scans and MRIs cannot take pictures of everything in the human body. By catching rays from a tiny dose of nuclear material in tracers, a gamma camera has the special capacity to capture images of blood and certain tissues invisible to other radiological equipment.