Search results
Results from the WOW.Com Content Network
A CT pulmonary angiogram, in this case showing pulmonary embolism of saddle-type, which becomes more radiolucent than the radiocontrast filled blood surrounding it (but it may be indistinguishable without radiocontrast). Contrast CT, or contrast-enhanced computed tomography (CECT), is X-ray computed tomography (CT) using radiocontrast.
Iodinated contrast may be toxic to the kidneys, especially when given via the arteries prior to studies such as catheter coronary angiography. Nonionic contrast agents, which are almost exclusively used in CT scans, have not been shown to cause CIN when given intravenously at doses needed for CT studies. [27]
Iodinated contrast contains iodine.It is the main type of radiocontrast used for intravenous administration.Iodine has a particular advantage as a contrast agent for radiography because its innermost electron ("k-shell") binding energy is 33.2 keV, similar to the average energy of x-rays used in diagnostic radiography.
It is marketed under the name Ultravist which is produced by Bayer Healthcare. It is a low osmolar, non-ionic contrast agent for intravascular use; i.e., it is injected into blood vessels. [2] It is commonly used in radiographic studies such as intravenous urograms, brain computer tomography (CT) [2] and CT pulmonary angiograms (CTPAs).
The radiation used in CT scans can damage body cells, including DNA molecules, which can lead to radiation-induced cancer. [148] The radiation doses received from CT scans is variable. Compared to the lowest dose X-ray techniques, CT scans can have 100 to 1,000 times higher dose than conventional X-rays. [149]
A contrast agent (or contrast medium) is a substance used to increase the contrast of structures or fluids within the body in medical imaging. [1] Contrast agents absorb or alter external electromagnetism or ultrasound , which is different from radiopharmaceuticals , which emit radiation themselves.
Opting for an alternative type of scan without contrast might result in a 10 to 20 percent reduction in diagnostic accuracy, he said. Other sources of the dye are limited, however.
Computed tomography angiography (also called CT angiography or CTA) is a computed tomography technique used for angiography—the visualization of arteries and veins—throughout the human body. Using contrast injected into the blood vessels, images are created to look for blockages, aneurysms (dilations of walls), dissections (tearing of walls ...