Fluoroscopy: basic science, optimal use, and patient/operator protection

Fluoroscopy is an x-ray-based medical imaging technique that is used when viewing a real-time process within the human body is important. Examples of use for fluoroscopy include swallowing studies, upper and lower gastrointestinal imaging, angiography, as well as device placements such as stents, needles, lines, and tubes. Because of its widespread applications, fluoroscopy is found in many areas of modern hospitals. Areas often using fluoroscopy include radiology, gastroenterology, surgery, pain management, cardiology, and others. Today, most modern units deliver x-rays as short pulses instead of continuously, thus lowering the radiation exposure to patients and operators. The source for x-rays in a modern fluoroscope is an x-ray tube. An x-ray tube is a device that permits the energy and number of x-rays produced to be controlled independently. Image receptors in fluoroscopy have recently undergone a revolutionary transformation from largely analog devices to mostly digital devices. Continuous mode fluoroscopy is a mode found on many older models and continues to be provided on some newer models. Variable frame rate fluoroscopy has been of substantial benefit to patents and operators. In this mode, an operator selects the frame rate or frames per second at which images will be collected. Radiation dose in fluoroscopy is directly proportional to the amount of time the x-ray beam is on. Distance is the single most important parameter that can be modified to minimize fluoroscopic operator dose. In adults, it would be advisable to keep the kVp in the range from 80 to 110 kVp for most routine applications to keep patient and operator doses reasonable. Overuse of magnification modes is also a major contributor to high patient and operator doses. Personnel protective apparel when using fluoroscopy as part of your practice is critical to staying safe.