High resolution chest computed tomography
Unlike the simple one in which a single radiological image is obtained; the tomography axial allows to obtain several radiological images in different planes of the anatomical area under study which will later be sent and processed on a computer to form a defined image that will be printed on a radiographic plate, on a CD or on the computer's hard disk. Depending on the anatomical area to be studied, the tomography It can have different names, the most common are:
- Skull Tomography
- Paranasal sinus tomography
- Thorax tomography
- Tomography of the abdomen
- Pelvic tomography
- Spinal tomography
High-resolution axial tomography is performed with more complex equipment than conventional axial tomography and allows a greater number of tomographic images to be obtained. It is used in very specific studies in which it is necessary to have a high definition in order to reach a diagnosis.
How is the CT study done?
The tomographic study is performed in the radiology room of the medical center or hospital by a radiology technician. The patient must undress the anatomical area under study; In some cases, you will be provided with a gown to cover yourself; at the same time you should remove your personal items, especially jewelry and metal objects that can interfere with radiological images. The patient will lie on a table that will slowly move into the scanner (in the form of a tube), once inside the scanner the patient must remain immobile until the end of the study. Inside the scanner, radiological images of the anatomical area to be studied will be obtained and they will be sent to a computer for their definition and subsequent study.
In some studies it is necessary to use a contrast that is introduced orally, rectally or intravenously (depending on the type of study) for a better definition of the images and a better diagnosis. The duration of the exam will depend on the area anatomy to be studied and the amount of images necessary to complete the study, generally it is about 30 minutes.
Preparation for the study.
The patient must undress the anatomical area under study and remove their personal items, especially jewelry and metal objects. The Tomographic study without contrast does not require prior preparation by the patient. The tomographic study with contrast requires avoiding the intake of liquids and solids between 4-8 hours before of the study. Some studies may require some prior preparation, in these cases the doctor or radiology technician must inform the patient of these conditions. The signing of an informed consent by the patient will be requested.
What does it feel like during and after the study?
The tomographic study without contrast is painless for the patient. The tomographic study with contrast it is painless for the patient Except for the discomfort of the administration of the contrast (body heat, bad taste in the mouth, nausea ...). The patient may have an allergy to the local anesthetic and / or the contrast used during the study. In the case of presenting skin rash, itching, or shortness of breath During the study, you must indicate this to the radiology technician immediately. It may be uncomfortable for the patient to have to remain immobile while the study is being carried out; in some studies you will be asked to take a deep breath and / or hold your breath for better image definition.
Radiology rooms must be kept at a certain temperature, generally below the temperature of other rooms. Some centers offer open scanners for people who are claustrophobic or obese.
Study risks.
The tomographic study without contrast, in general, does not imply a risk important to the patient's health. The tomographic study with contrast, in general, does not imply a significant health risk except those inherent to the use of contrast such as intolerance and / or allergy that can be treated at the moment (severe anaphylactic reaction is exceptional). In both studies, the type of radiation as well as the dose used follows strict safety controls and in general the benefit obtained outweighs the minimal risks of the radiation itself.
The risk of radiation is cumulative dose (higher risk at higher dose) so they must avoid the indication of unnecessary studies or repetition of them as far as possible. The embryo, fetus, and children are more susceptible to radiation, so in these cases unnecessary studies should be avoided. The pregnant or suspected pregnant woman (including those with an IUD) should avoid the study as much as possible and should tell the radiology technician that they are pregnant before having a CT scan.
Contraindications to the study
The patient should consult with his doctor before carrying out the study in case of:
- Pregnancy and breastfeeding.
- Contrast allergy in contrast studies.
- Renal failure in contrast studies
- Perform some type of treatment
What is a CT scan done for?
Non-contrast and contrast-enhanced tomography is a relatively simple and safe test, widely used in the field of Medicine since it provides very valuable information for the doctor about the internal organs. Allows the diagnosis and monitoring of multiple pathologies such as cysts, herniated discs, among others; at the same time it serves as a screening test or diagnostic suspicion of multiple local or systemic processes such as infectious, inflammatory and / or tumor processes that must be confirmed later with specific studies. It is used for staging of tumor diseases. It is a basic study for certain surgeries since it allows to establish the exact size and location of the lesions susceptible to surgical treatment.
High-resolution chest axial tomography is performed mainly to study different pulmonary processes (inflammation, infection, tumor processes ...) that have not been identified with other simpler diagnostic techniques and in the course of which, the patient remains symptomatic.
(Updated at Apr 14 / 2024)