Description

Contrast dye helps highlight some areas better on CT images. For example, it can highlight and emphasize blood vessels, intestines, and other areas. The dye is given through an intravenous line inserted into a vein of your arm or hand.
Often, images are first taken without contrast, and then again with contrast. However, use of contrast dye isn’t always necessary. It depends on what your doctor is looking for.
Your doctor may direct you not to eat or drink for several hours before the test if you’re going to receive contrast dye. This depends on your particular medical condition. Ask your doctor for specific instructions for your CT scan.