Nuclear Medicine

Nuclear medicine imaging provides your child's doctor with information about the structure and function of internal organs. This imaging uses very small amounts of radioactive materials (radiopharmaceuticals) to diagnose and treat conditions. During imaging, special types of cameras detect the radiopharmaceuticals injected into your child’s body. These cameras work with computers to provide pictures of the area of your child’s body being studied. Nuclear medicine allows doctors to gather medical information that would otherwise be unavailable except through surgery or other more expensive and invasive diagnostic exams.

Nuclear medicine exams can provide early diagnosis of many conditions and are frequently ordered by physicians in a variety of specialties.

Nuclear medicine exams can:

Assess gallbladder function
Assess gastric motility (movement of food through the digestive system)
Assess kidney function
Assess thyroid function
Determine blood flow to the brain
Determine blood flow to the heart muscle
Determine how well kidney, heart and liver transplants are working
Determine the place in the brain where seizures start
Identify infection within bones
Locate fractures in bones before they can be seen on X-rays
Visualize tumors

The nuclear medicine team at Riley at IU Health participates in the Image Gently campaign and follows the As Low As Reasonably Achievable (ALARA) principle. The doses given to your child are based on age and weight to minimize his or her exposure to radiation. The amount of radiation in a typical nuclear imaging procedure is comparable to that received during a diagnostic X-ray.

Nuclear medicine images are not instant pictures like X-rays or computed tomography (CT) scans. The images are built slowly as radioactivity comes out of your child’s body and accumulates over time in a special detector. Imaging can take as little as one minute to as much as two hours depending on the type of study. In many cases, images must be taken at different time intervals (for example, two hours apart, four hours apart or 24 hours apart).

Riley at IU Health offers many different types of nuclear medicine tests to fit your child’s needs and allow doctors to make the best diagnosis possible. Tests offered include:

Single-photon emission computerized tomography (SPECT/CT). Single-photon emission computerized tomography (SPECT/CT) allows doctors to gather information about the look and function of your child’s organs. The unique feature of this scanner is that it is equipped with CT technology that allows mapping of this information to precise areas of the body. This CT scan is only completed if necessary. Once both sets of images are taken, a software program fuses the images together. This allows the doctor to pinpoint the exact location of any functional problems and make more accurate diagnoses.
Gastric emptying study. This test evaluates the emptying of the stomach and also may provide information on the presence of reflux from the stomach to the esophagus.
Hepatobiliary iminodiacetic acid (HIDA) scan. This radiology imaging test helps determine if the gallbladder and hepatobiliary system (ducts that connect the gallbladder to the liver and small intestine) are working properly. A small amount of dye is injected through the vein.

What to Expect

Depending on what type of test your child is undergoing, the radiopharmaceutical will be administered in one of many ways. Many nuclear medicine exams require the use of an IV to inject the radiopharmaceutical into your child’s veins. Other nuclear exams may require that your child eat or drink the radiopharmaceutical. In this case, the radiopharmaceutical is mixed with food (scrambled eggs, milk or baby formula) or given in a pill to be swallowed. There are also exams that require the radiopharmaceutical to be inhaled into the lungs or injected through a bladder catheter.

Some exams require a waiting period between the time the radiopharmaceutical is administered and the time the images are taken. This wait time can range from two to 24 hours depending on the type of exam. In certain cases, the radiologist may use sedation or diagnostic and interventional anesthesia to reduce the possibility that your child will move during longer imaging studies.

Follow the preparation recommendations of your child’s doctor or nurse before the nuclear medicine test. Preparation will vary depending on your child’s specific imaging procedure.

Single-Photon Emission Computerized Tomography (SPECT/CT)

A typical nuclear medicine procedure performed with a SPECT/CT scanner consists of the administration of a radioactive tracer, typically through an IV. After a delay to allow the body to absorb the radiopharmaceutical, your child will lie down on the imaging table while the scanner obtains images. The images do not show anatomic details but instead map out areas of normal or abnormal organ function in the body.

Gastric Emptying Study

It is important that your child not eat or drink anything for up to eight hours before a gastric emptying study to ensure that the stomach will be empty at the time the test begins.

For the liquid-meal version of this test, your child will drink the mixture and lie flat on the table. A special scanner will take pictures of the stomach every minute for approximately 60 minutes. The results will provide information about whether gastroesophageal reflux disease (GERD) is present and the rate of stomach emptying.

For the solid-meal version of the test, your child will eat a meal of egg and toast mixed with the radiopharmaceutical. Your child will have special X-rays taken right after the meal, two hours after the meal and, if needed, four hours after the meal. The results provide information on the rate of stomach emptying.

Hepatobiliary Iminodiacetic Acid (HIDA) Scan

A hepatobiliary iminodiacetic acid (HIDA) scan is performed by a certified nuclear medicine technologist and reviewed by a nuclear medicine radiologist.

Your child must have an empty stomach before the HIDA scan. The doctor will provide specific eating and drinking instructions at the time the exam is scheduled.

You can expect the following during a HIDA scan:

You can stay with your child during the exam. However, additional children may not come into the exam room. They will need to be watched by another adult.
Your child will be asked to lie down on a soft table. He or she will be safely restrained.
The technologist will insert an IV tube into a vein and administer the radiopharmaceutical.
Pictures will be taken for one hour.

Some HIDA scans use cholecystokinin (CCK). CCK is an enzyme made by the body that makes the gallbladder contract. CCK will be given through the IV over a one-hour time period, and a final picture will be taken at the end. Calculations will be done to determine how much the gallbladder empties (ejection fraction).

More pictures may be needed after the radiologist looks at the first set of images. If so, they will be taken three hours later and/or 24 hours later. The technologist will tell you what time to come back. The extra pictures will take about 10 minutes.

Your child may return to his or her normal activities after the exam. The results of the HIDA scan will be sent to your child's doctor.

Locations

In addition to our primary hospital location at the Academic Health Center in Indianapolis, IN, we have convenient locations to better serve our communities throughout the state.