Imaging Tools to Aid Diagnosis
At Swedes, our medical imaging professionals use a wide range of technologies to help diagnose health issues.
Here are some of the more common tools we use:
Radiology uses X-rays to create pictures of the human body. X-rays are beams of high-energy, invisible light that pass through the body. Some of the thick body parts, like bones or solid organs, stop more X-rays than other body parts. X-rays are particularly good for getting images of bones, the chest and the abdomen. Sometimes the radiologist or radiographer gives the patient a special dye to outline body parts, showing how they work. Sometimes the radiologist will use a special kind of X-ray to take moving pictures that could be useful for areas such as the stomach or bowel.
Computed Tomography (CT) uses an X-ray machine, a radiation detector that surrounds the patient and a high-speed computer. CT uses a narrow X-Ray beam and a computer to reconstruct the image, so it can produce slices of body parts.
This involves using a small amount of a radioactive substance to better see images from inside the body. A special device called a gamma camera detects the radiation coming out of the patient’s body for doctors to see areas of concern. Although nuclear medicine involves radioactivity, the amount of radiation exposure that a patient receives in nuclear medicine is comparable or often less than that received in radiography or CT. Positron Emission Tomography (PET) is a specialized type of nuclear medicine, often done to evaluate the whole body rather than only a particular organ.
Ultrasound uses sound waves to image the body. Ultrasound is often better at imaging soft tissues and is safe for unborn babies. The technologist that performs ultrasound exams is a sonographer, producing images called ultrasound scans or sonograms. The technologist places a device called a transducer against the patient's skin, using a gel to produce good skin contact. The transducer gives off sound waves, which reflect back and are converted into a picture by the computer.
Although an MRI scanner may look like a CT scanner, it produces images in a very different way. MRI does not use radiation, but a very strong magnet and pulsed radio waves. During an MRI, the body produces radio waves that are turned into pictures by a computer. MRI is very good at seeing differences between soft tissues--especially for the brain, the spine and joints.