Fluoroscopy represents a special examination method. In technical language, it is also called fluoroscopy. It is an examination method based on X-rays.
What is fluoroscopy?
Fluoroscopy represents an examination method in which X-rays are used to trace and image processes and motion sequences. In contrast to simple X-rays, fluoroscopy involves continuous observation. A kind of image series is generated. This image series makes it possible to visualize dynamic processes in the human or animal body and observe them in real time.
Function, effect and goals
Fluoroscopy or X-ray fluoroscopy represents a special X-ray procedure. Therefore, like normal X-ray, the image or images are obtained using X-rays. For the duration of fluoroscopy, low-dose X-rays are continuously directed at the patient’s body or the appropriate part of the body to be imaged. A special detector then intercepts the X-rays. From here, they are directed to a so-called image converter, which displays the process to be observed in the body on a monitor. The images produced in this way are two-dimensional. Fluoroscopy is mainly used for diagnostic purposes. Thus, the method of fluoroscopy has proven itself when it comes to imaging the processes in the esophagus, stomach, diaphragm, duodenum or the entire intestine. A frequent application is the examination of dysphagia, for which altered esophageal motility may be responsible. In addition, fluoroscopy is also suitable for visualizing venous vessels and for examining the lungs. For example, pulmonary nodules, certain types of shadowing of the lungs, can be localized and imaged. More rarely, the fluoroscopy method is also used in the area of the joints in order to be able to understand the course of joint movement. Furthermore, fluoroscopy is used in the examination of the kidneys and the urinary tract. A particular advantage of this examination method is the very precise possibility of localizing organs, specific tissues or problem areas in organs. This is due to the fact that the imaging geometry of fluoroscopy is cone-shaped. For this reason, it is sometimes referred to as cone beam CT or cone beam tomography. However, fluoroscopy is not only used for diagnostic purposes. It also plays a major role in surgical procedures. Here it is used above all to check the position of bones, implants and pacemakers. In the same way, fluoroscopy is used for orientation when positioning stents or catheters. Some applications of fluoroscopy require the prior administration of a contrast agent. Depending on the organ or joint to be examined, the contrast agent is either swallowed or administered intravenously. Various types of contrast media are used in connection with fluoroscopy. These contrast media are special preparations developed for X-ray procedures. The X-ray contrast media are based on either iodine or barium. Most often, contrast agents are used when imaging organ movement, such as in the gastrointestinal tract. If a contrast agent must be administered for the intended examination, the patient must either drink it beforehand or receive it intravenously. During the examination, the patient lies either on or in front of a tilting examination table. In some cases, the patient also stands in front of the tilting examination table. This depends on where the organ or joint to be examined is located in the body. Some procedures can also be observed only when the patient changes position during the examination.
Risks, side effects, and hazards
As with any ordinary X-ray examination, X-rays are inevitably used. These are weak X-rays. Nevertheless, the examination is accompanied by radiation exposure, so that fluoroscopy, for example, may not be performed – at least not without further ado – on pregnant patients. The intensity of the radiation exposure depends on the purpose for which the fluoroscopy is performed.In general, radiation exposure lasts longer with fluoroscopy than with a normal X-ray image. However, this does not mean that the radiation exposure must therefore necessarily be higher. In the past, this was the case because the imaging technology was not yet so advanced. Today, the technique of so-called pulsed fluoroscopy is used. This makes it possible to work with a much lower radiation intensity. If it is only a question of checking the position in the context of an operation or in the run-up to another examination, very low radiation is required nowadays. In these cases, fluoroscopy actually has a lower radiation exposure than a classic overview image obtained by normal X-ray. However, complications can arise if the patient has to take a contrast medium and cannot tolerate it. It happens again and again that patients react allergically to contrast media. Therefore, special caution is required, especially for patients who are generally prone to allergies. It is therefore advisable for patients who have a known allergy to inform the physician or medical-technical assistant of the allergy in good time. It is then often possible to switch to a contrast medium with a different active ingredient. In some cases, the contrast media can also cause nausea and sensitivity to light following the examination. Depending on the contrast agent used, it may therefore be necessary to avoid direct sunlight for approximately 24 hours to prevent the development of pigment spots.
