Sonographers, also called ultrasound technicians and diagnostic medical sonographers, use ultrasound high frequency sound waves to produce images of internal body tissues. This helps doctors diagnose and monitor a variety of conditions such as heart disease, pregnancy and cancer.

MRI technologists run the magnetic resonance imaging scanner to create a diagnostic image for the physician. They maintain imaging equipment and ensure that their patients are protected and in an optimal position for imaging. ... An associate degree is generally the minimum education required for this position.

Using devices such as computer tomography (CT) scanners and magnetic resonance imaging (MRI) machines. Performing or directing radiology staff to carry out image-guided, diagnostic procedures. ... Interpreting the results from diagnostic imaging procedures to determine diagnoses

A PET technologist usually begins each procedure by explaining the process to the patient, emphasizing the minimal quantities of radiation involved and the large safety margin built into the procedure. The patient reclines on a table during the test and is passed through a doughnut-shaped scanner that detects positron emissions from the radioactive drugs. The machine creates an image that shows a "map" of the body's tissues, with the areas of heavier and lighter radioactivity marked in different colors. Superimposing the PET image over a CT or MRI image makes it even more useful, combining information on the tissues' appearance and function in a single image. Most modern machines combine PET and CT scanning.