the use of ultrasound inside a blood vessel to visualize the interior of the vessel in order to detect problems.

A new investigational technique where ultrasound crystals are placed on a catheter (during a heart catheterization) to see blood vessels "from the inside". This technique is particularly helpful in cases of complex narrowing (stenoses), as may occur in the aorta (coarctation), or pulmonary arteries.

Intravascular ultrasound (IVUS) is a medical imaging methodology using a specially designed catheter with a miniaturized ultrasound probe attached to the distal end of it. The proximal end of the catheter is attached to computerized ultrasound equipment. It allows the application of ultrasound technology to see from inside blood vessels out through the surrounding blood column, visualizing the endothelium (inner wall) of blood vessels in living individuals.