Radiologic Technology

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Radiologic technology


Radiologic technology is a general term applied to the allied health profession that encompasses the use of ionizing radiation (x-ray), sound or radio waves, radioactive substances to produce an image, and magnetic imaging. These resultant images are used by the radiologist to help in making a diagnosis.


Radiologic technology is a broad-based category that includes general x-ray, ultrasound, mammography , nuclear medicine, computerized axial tomography (CAT scan), radiation therapy, and magnetic resonance imaging (MRI). General x-ray technology is a primary link between the physician and the diagnosis. X rays are often required so that the physician can diagnose and treat the patient based on the patients' complaints or conditions.

The x-ray image is created by the controlled and careful use of radiation through the body part being examined. The image is captured on a film, which is placed under the patient. The x-ray beam passes through the body part being examined, and creates a latent image on the film. The latent image is processed, and then is evaluated by the radiologist, with the written and/or verbal report given to the referring physician. Some examples of subspecialties of medical radiography are contrast studies, pediatrics, trauma, surgery, and special procedures (e.g., angiography or other interventional procedures).

Mammography is another name for breast imaging and evaluation of breast disease. Mammographers are radiographers who are proficient in screening and diagnostic imaging, as well as such interventional procedures as needle localizations (pre-biopsy), core biopsies, and breast ultrasound.

Ultrasonography is the imaging of anatomy using high-frequency sound waves. The sonographer obtains diagnostic images or patterns that the physician evaluates in the diagnosis of disease. A scan is created by using gel and a transducer, or probe, moving it over the surface of the relevant anatomy. The transducer bounces sound into and back from the anatomic area, and an image is then created on the monitor attached to the machine. This specialty has several distinct areas: abdominal ultrasound , adult and pediatric echocardiography , obstetrical-gynecological ultrasound, and vascular ultrasound.

Nuclear medicine is very different from medical radiography, because in radiography the x-ray beam from the machine is the source of radiation. It is instantaneous, and is controlled by the technical factors selected by the radiographer. In nuclear medicine, the patient becomes the source of radiation, and the radiation itself is constantly emitted. The patient orally ingests or is intravenously injected with a radioactive substance, or radioisotope. The images are 'collected' via the nuclear medicine camera sorting radioactive signals from the patient. The radioactivity levels are different for the body part or organs being imaged. The nuclear medicine technologist has protocols that are followed for selecting the type of radioisotope to inject, based on the exams ordered.

Computerized axial tomography, or CAT scans, are studies that image the body using multiple projections of the x-ray beam to created sectional images of an organ or anatomic region. These axial sections are selected and manipulated by the technologist, using computer programs that direct the protocols for these exams.

The radiation therapy technologist applies therapeutic radiation doses in strictly controlled circumstances to cure

or arrest disease. In daily or weekly contact with the cancer patient, and working directly with the physician, the technologist assists in the calculation of radiation dosage, and operates a variety of sophisticated radiation treatment equipment and instruments, including computers.

MRI (magnetic resonance imaging) uses radio waves and a strong magnetic field rather than ionizing radiation to provide three-dimensional images of the organs or body structures being examined. The technique has proven critical in diagnosing a variety of conditions throughout the body, including cancer, cardiovascular disease, stroke, and bone and joint disorders. MRI requires specialized equipment and expertise; and allows evaluation of some body structures that may not be as visible with more conventional imaging methods. MRI is highly accurate in showing soft tissue structures near and around bones, the cardiovascular system , as well as major organs. Additionally, because it is a non-ionizing

modality, it is gaining increasing popularity in imaging the reproductive system.

Work settings

The majority of radiology technologists work in a hospital setting. Others are employed in government, health industries, public health , mental health, education, private offices and clinics. Those professionals with advanced degrees might also pursue careers in the areas of management, quality control, equipment maintenance, or application specialties.

Education and training

The radiologic technologist must first complete a two-year accredited radiology technology program. This consists of both classroom and clinical training. Typically, student radiographers will demonstrate their ongoing training in the classroom, and will rotate through each segment of the radiology department. The students will work with the registered technologist, and must show clinical competency prior to working independently. The students will pass clinical tests in order to progress through the training process. Upon completion of the program, the students will be required to take the national registry exam given by the American Registry of Radiologic Technology (ARRT). This is a national registry for technologists who pass and maintain the standards set forth by this organization.

Advanced education and training

For those radiographers that choose to specialize in the previously mentioned areas, further study is mandated. In some cases, both clinical and didactic requirements exist. Some disciplines will require approximately one year beyond the requisite radiography coursework, such as sonography, CAT scan, MRI, and mammography. For a nuclear medicine technologist, it is the standard to obtain a four-year university degree. In each case, the technologist needs recorded hours of clinical experience in the core discipline. The registered technologist (RT) must also document 24 hours of continuing education credits every two years in order to maintain certification and compliance with the ARRT as well as with state and federal agencies that regulate certain areas such as mammography.

Future outlook

Employment opportunities for radiologic technologists continue to expand. These professionals are expected to be increasingly in demand due to technological expansions, and the increased need for faster, more detailed diagnoses. As technology refines, so must the varying disciplines of radiologic technology. With the introduction of digital imaging, and better quality equipment and contrast media, changes continue at breakneck speed. In addition, access to higher technology has become more widespread as these newer modalities become the gold standard in some cases. Although this is positive for the profession, there continues to be a shortage of primary x-ray technologists, as those new graduates pursue specialties and bigger salaries. This specialization, while important, has caused serious hardship in many radiology departments, working with staffing shortages and creating tech fatigue, while the demand remains high. This is a challenge that is being addressed industry-wide.


Contrast —A substance used by injection or ingestion to demonstrate certain organs or anatomy.

Latent image —The x-ray image created on film, prior to development.

Processing —Film development.

Radioactive —Giving off radiation.

Radioisotope —A chemical element used in injections for nuclear medicine that can be detected in the body by the emission of radiation.

Radiologist —The physician who interprets the films and makes a diagnosis.



Brant, William E., and Clyde A. Helms, eds. Fundamentals of Diagnostic Radiology. Lippincott, Williams & Wilkins

Publishing, 1999.


Cruise, Kristi R. L. and James Robert Cruise. "Radiology Administrators' Opinions of Education." Journal of the American Society of Radiologic Technologists 72 (March-April, 2001), 314-319.


American Society of Radiologic Technologists (ASRT). 15000 Central Ave. SE, Albuquerque, NM 87123-3917. (800) 444-2778 or (505) 298-4500. Fax: (505) 298-5063. <>.

Radiological Society of North America (RSNA). 820 Jorie Boulevard, Oak Brook, IL 60523-2251. <>.

Debra Novograd, B.S., R.T.(R)(M)