Preparation of the CT thorax
Before performing a CT thorax to visualize the lungs, there is always a consultation with a doctor. This preliminary talk serves to explain the benefits and risks of the examination. The patient should be informed about the radiation exposure during imaging. If a contrast medium is planned to be administered, the physician must be informed about the intake of medication, known intolerances and allergies as well as existing previous illnesses (e.g. liver and kidney diseases). In most practices and clinics, the patient should be fasting for 6 hours in order to ensure better quality of the images.
Procedure of the CT Thorax
During imaging, the patient is placed on a kind of table, which is increasingly moved into the CT device during the examination. During the examination, the X-ray tube and the opposite detector system rotate around the patient, allowing the individual layers of the body to be recorded. Compared to an MRI machine, the CT tube is so short that the patient can look out of the tube during the entire examination and there is usually no need to fear claustrophobia.
Nevertheless, a sedative can be administered before the examination. No other person is in the room during the imaging in the CT unit. The patient can call the staff at any time via an intercom system. To examine the lungs, the patient must hold their breath for about 10 to 20 seconds at regular intervals to ensure good quality of the images taken and to show the lungs in their unfolded state. Depending on the question, the patient is administered a contrast medium approximately 1 hour before the examination.
Do you always need contrast medium?
The administration of an iodine-containing contrast medium depends on the problem under investigation. The contrast medium is used to improve the imaging of structures with blood circulation. Inflammations and tumours in particular turn a strong white colour after administration of the contrast medium and can be distinguished from their surroundings.
In addition, the contrast medium is also suitable for imaging a pulmonary embolism, as the colour of the blood differs significantly from that of the thrombus. Various side effects can occur when a contrast medium is administered. In a preliminary consultation, the doctor should be informed about known intolerances, allergies and previous illnesses.
Findings of a CT thorax
The images taken during the examination are normally viewed directly afterwards by a doctor. The doctor can usually report the first results immediately. However, since up to 100 images can be taken in total during a CT imaging, the doctor only prepares a written report after detailed evaluation. This report is usually forwarded to the doctor in charge within a few days.
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