This is because the uses state
The-art technology, capable of capturing several radiographs at once to offer a broad view of the studied area. When performed without contrast , the test is faster and offers reduced risk to the patient . I explain more about the indications, types and differences between CT with and without contrast throughout the article. At the end, I present tips to optimize the issuance of the tomography report through . What is non-contrast tomography? Non-contrast tomography is a test that uses ionizing radiation and a rotating tube to form images of the inside of the body. The absence of contrast occurs when it is not necessary to show certain low-density structures , such as organs and blood vessels.
In this scenario, the exam is requested
Using only the computed tomography technique , which captures records from the emission of X-ray beams. Once the radiation crosses the studied region, part of it is absorbed, while the remaining rays reach a detector inserted in the table of the CT scanner . This leftover signal is transformed into pixels , which are the smallest dots in a digital image. What is the difference between contrast and non-contrast tomography? The dynamics for performing the exam is the same, whether with or without contrast. With the difference that the inclusion of contrast requires a different preparation , with fasting and a step for administering the iodinated contrast medium.
Generally it is injected intravenously
A few minutes before the acquisition of tomographic images, so that it is in the desired location when the records are taken. The use of contrast emphasizes structures that rarely appear in detail on CT results. I’m talking about the soft parts, which absorb little ionizing radiation due to their low density. While bones and other hard tissues let few rays pass through, being portrayed clearly in the images, soft tissues allow most of the radiation to pass through them. As a result, they appear in shades of dark gray on tomography, preventing a detailed assessment. The use of contrast is a solution for these areas to be highlighted in the records.