Does ultrasound require injection of dye?

i'm considering ultrasound screening for carotid artery blockage and for aortic aneurysm....but I'm allergic to many of the dyes used in radiology....do these tests require injection of dye, or is it like the ultrasound they do when you're pregnant, where they just run the wand over your skin?

An ultrasound of any vessel does not require a contrast media. The contrast agents used in radiology would have no use in u/s because u/s does not use radiation. But, U/s visualizes movement of blood within a vessel, and one can see that without any type of contrast media. Most MRIs of vessels do not require a contrast agent, but if contrast is used, it is totally different than x-ray contrast....MRI also does not use radiation to gather images.

The actual procedure is a lot like when you are having an OB u/s. You lay on a table, a gel is applied to the area of interest (neck or abdomen in your case), and the technologist moves a transducer (wand) over your skin. Painless, fairly quick, non-invasive and pretty easy!

There is at least one clinic in my town that specializes in ultrasound exams for heart and artery condition. They do not do any injection whatsoever, and nothing orally given either.

I can't say if it's the same equipment or testing that you are considering though.

You will be asked to lie down on an examination table. The technician (or physician) will place a clear gel on the area of the neck where the carotid artery is located, this gel allows the transducer to slide easily on the area.
When the transducer is placed against the skin, an image of the artery is shown on a video screen. To view the arteries from many different angles, your doctor will re-position the transducer several times. Because blood is flowing through the artery, a sound similar to your heartbeat will be heard.

The procedure is repeated for the carotid artery on the other side of the neck. A carotid ultrasound usually only takes 15 to 30 minutes to complete and the results are immediately known by your doctor.

nope, ultrasounds are just the same as when your pregnant, no dyes at all :]