It is unlikely that contrast would be injected into an artery for a CT. When the intravenous line is inserted, it is usually obvious the line is in an artery by accident; these clues include a bright-red flash of blood in the cannula, pulsatile movement of blood in the line, and/or intense pain or burning at the site of injection. If this occurred, the line would be removed and pressure would be applied for an extended period of time, then a new line would be placed into the vein.
When a CT is performed, the intravenous contrast is always injected into the vein. What is adjusted is how much time the machine waits after injection to obtain images. The protocol selected depends upon the clinical indication. In most cases for body CT, the images are obtained during the venous phase. However, there are some exceptions, with representative scenarios as follows: If the study indication is to rule out aortic aneurysm or dissection, the images will be obtained when the most contrast is in the aorta/arteries. If the study indication is to rule out pulmonary embolism, the images will be obtained when the most contrast is in the pulmonary artery. If the study indication is to characterize a liver mass, the images will be obtained in precontrast, postcontrast arterial, postcontrast venous, and sometime postcontrast delayed phases.
Let me start by saying that it happens very rarely. It happens sometimes when the patient has a uncommon variation in vascular anatomy.
if contrast is injected through an artery, it probably means that the CT scan has to be repeated.
Did you have a second CT scan?