Computed tomography (CT)
The computed tomography is a special, quick and easy to be performed X-ray method in medical diagnostics and therapy. Through a special X-ray technology non-superimposed tomographic (slices) images are created by sections. Sectioning (slicing) allows for a three-dimensional assessment of the body and organ structures. The CT can be used for representation and evaluation of various pathological changes throughout the whole body.
What is a CT scan?
Computed tomography is a method of examination in diagnostic radiology and an advanced development of the classical X-ray technology. It is a specific method in which sectional images X-rays can produce three-dimensional images. Individual layers of the body are displayed without superimposition (overlapping).
How does a CT scan function?
A CT consists of an X-ray tube (CRT) and an opposite image acquisition system (detector). Both components rotate around the patient during the study (in contrast to the classical X-ray, where only images from one direction are taken). The X-ray tube only supplies a narrow beam which penetrates the body and in the organ to be examined and penetrates it. Then, it is measured how much of the weakened beam still arrives on the other side at a high-sensitive sensor. Since detector and the tube uniformly rotate around the patient (usually spirally) different weakened rays or signals coming from different directions. This usually happens simultaneously, so that today we speak of the so-called multisclice technology. This method allows for a significantly shorter examination time (just a few minute) in comparison of the examination time of previous generations of devices. Through targeted control set in accordance with the relevant medical issue, the radiation exposure can be greatly reduced. The attenuated signals are processed electronically and processed by a special computer program. The computer creates from the individual signals images called tomograms. Since the various organs and tissues (bone, muscle, fat) attenuate the X-rays in different ways, they can easily be distinguished in the CT image.
For what problems or diseases is this method suitable?
In principle, the whole body can be examined:
- Facial skull (e.g. ENT medical issues in the sinus area, but also temporal bone, middle and inner ear)
- Lung / chest
- Internal organs of the abdominal and pelvic cavity, such as also in oncology or in cancer in the follow-up;
- Bony structures, for example with conventional radiographs or only insufficient to be assessed bone injuries
- Osteo CT / Bone Densitometry
The CT scan is perceived by many patients as less stressful than the MRI scan, since the device is less restrictive and does not take so long for examinations. Additionally, there are no problems with pacemakers. We have a modern multi-slice computed tomography of the manufacturer Siemens. The device consists of a table unit on which the patients rest during the examination and the actual computer tomography - simplified described a large ring, which can be tilted corresponding to the required examination.
How is the examination performed?
After appropriate preparation, the patient is positioned on the examination table by the technologist (specially trained assistant). The medical examination is carried out with as little radiation as possible. Here, the table moves during the measuring through the wide opening in the actual device. Depending on the health problem, the patient receives breathing commands through a speaker system. In studies of the abdominal region, the patient has to prepare for the examination by having him or slowly drink a heavily diluted contrast agent over a period of about one hour.
Sometimes it is necessary to administer an additional contrast agent via a thin indwelling cannula into a vein in the arm of the patient. There may be a harmless effect such as the feeling of warmth and a slightly metallic chemical taste in the mouth. These contrast agents leave the body in a natural way. Allergic reactions are rare due to improved contrast substances; however, our team is well prepared for such an eventuality. With significantly reduced renal function, known intolerance to iodinated contrast substance and hyperthyroidism a contrast substance might have to be dispensed with. All this will be discussed with you prior to the examination. After the examination, the physician will discuss the results with you.
In studies with contrast substances, patients should fast three hours prior to the examination. However, necessary medication can be taken.
Who cannot be examined (contraindications)?
As with all X-ray examinations, pregnant women should be examined only if necessary.
Who pays for the examination?
Computed tomography is a standard benefit of all statutory and private health insurance.