A DEXA scan is an imaging test that measures bone density (strength). DEXA scan results can provide helpful details about your risk for osteoporosis (bone loss) and fractures (bone breaks). This test can also measure your body composition, such as body fat and muscle mass.

Diagnostic ultrasound, also called sonography or diagnostic medical sonography, is an imaging method that uses high-frequency sound waves to produce images of structures within your body. The images can provide valuable information for diagnosing and treating a variety of diseases and conditions.

Echocardiography is a diagnostic test which uses ultrasound waves to make images of the heart chambers, valves and surrounding structures. It can measure cardiac output and is a sensitive test for fluid around the heart (pericardial effusion). It can also be used to detect abnormal anatomy or infections of the heart valves.

Fluoroscopy is a study of moving body structures--similar to an X-ray "movie." A continuous X-ray beam is passed through the body part being examined. The beam is transmitted to a TV-like monitor so that the body part and its motion can be seen in detail. Fluoroscopy, as an imaging tool, enables physicians to look at many body systems, including the skeletal, digestive, urinary, respiratory, and reproductive systems.

A 3D mammogram (breast tomosynthesis) is an imaging test that combines multiple breast X-rays to create a three-dimensional picture of the breast. A 3D mammogram is used to look for breast cancer in people who have no signs or symptoms.

You’ve probably heard about the test called magnetic resonance imaging or MRI. In this test, radio waves, a magnetic field, and a computer create a scan of your body parts to look for health problems.

Magnetic resonance angiography–also called a magnetic resonance angiogram or MRA–is a type of MRI that looks specifically at the body’s blood vessels. Unlike a traditional angiogram, which requires inserting a catheter into the body, magnetic resonance angiography is a far less invasive and less painful test.

During magnetic resonance angiography, you lie flat inside the magnetic resonance imaging scanner. This is a large, tunnel-like tube. In some cases, a special dye, known as contrast, may be added to your bloodstream to make your blood vessels easier to see. When needed, the contrast is given with an intravenous (IV) needle.

Ultrasound is a safe and painless procedure that produces images of the inside of the body using sound waves. Ultrasound scanners consist of a console containing a computer and electronics, a video display screen and a transducer that is used to do the scanning. The transducer is a small hand-held device that resembles a microphone, attached to the scanner by a cord. Ultrasound imaging, also called sonography, involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High frequency sound waves are transmitted from the probe through the gel into the body. The transducer collects the sounds that bounce back and a computer then uses those sound waves to create an image. Ultrasound exams do not involve radiation exposure.

Conventional ultrasound displays the images in thin, flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats the sound wave data into 3-D images.
An echocardiogram (echo) is a graphic outline of the heart's movement. During an echo test, ultrasound (high-frequency sound waves) from a hand-held wand placed on your chest provides pictures of the heart's valves and chambers and helps the sonographer evaluate the pumping action of the heart. Echo is often combined with Doppler ultrasound and color Doppler to evaluate blood flow across the heart's valves.

Nuclear medicine is a specialized area of radiology that uses very small amounts of radioactive materials, or radiopharmaceuticals, to examine organ function and structure. Nuclear medicine imaging is a combination of many different disciplines. These include chemistry, physics, mathematics, computer technology, and medicine. This branch of radiology is often used to help diagnose and treat abnormalities very early in the progression of a disease, such as thyroid cancer.

A positron emission tomography (PET) scan is an imaging test that can help reveal the metabolic or biochemical function of your tissues and organs. The PET scan uses a radioactive drug (tracer) to show both normal and abnormal metabolic activity. A PET scan can often detect the abnormal metabolism of the tracer in diseases before the disease shows up on other imaging tests, such as computerized tomography (CT) and magnetic resonance imaging (MRI).