Computed Tomography (CT)
When is this exam indicated?
This imaging technique has detailed spatial resolution with very high temporal resolution. It can be used to depict cardiac and vascular disease, define size and location of tumors, characterize tumors and monitor response to treatment. CT imaging is used in emergency situations or to guide biospies or interventional techniques. CTs can be acquired with or without contrast agent. Coronary CT angiography is currently used to exclude coronary artery disease. In our Hospital a program of Low-Dose CT for Lung Cancer Screening is also available.
How is it performed?
The patient is placed on a bed that moves inside a circular device (gantry) in which the X-ray source and the signal detection devices (detectors) are located. The signal obtained is then processed by a computer that provides images of the district examined. Staff will operate the CT scan from the next room with whom you can talk during the exam. You may be asked to breathe in, breathe out or hold your breath at certain points. The length of the exam depends on the district under study. In most cases, an intravenous constrast agent injection is required during the CT acquisition.
If a contrast agent is administered and you are known to have allegries, you will need to tell staff when you book your exam as they will need to prepare you for the exam. You must refrain from eating for at least 12 hours prior to the exam and can intake liquids, unless otheriwise indicated.
Several examinations use x -rays that produce radiation called "ionizing" radiation, that can induce damage to biological tissues. CT uses a small amount of radiation to obtain diagnostic images . In some cases, the amount is even lower than the amount of radiation normally received from sunlight. The risk of tissue damage resulting from this exposure is therefore also extremely low and the risk associated with not performing the examination is generally greater than the risk of dmaging ioniziang radiation. In order to minimize this risk as much as possible, for each examination with radiation we check whether it is really necessary (principle of justification) and, if so, we use the lowest possible radiation dose that allows us to obtain the best result (principle of optimization). The maximum optimization of our equipment is ensured by the constant control of a Specialist in Medical Physics that guarantees the maintenance of maximum efficiency. Women of childbearing age must exclude pregnancies in progress. In case of pregnancy, even if only suspected, it is essential to notify the physician, who will assess the advisability of the examination and, if the assessment of the risk-benefit ratio proposes its execution, will need to require an additional appropriate consent and notify the staff for the necessary precautions.