Cincinnati Researchers Use Doppler Ultrasound To Spot Early Signs Of Blocked Arteries

The method, which relies on Doppler ultrasound, was described in a presentation by physics graduate student Megan Miller Nov. 2 during the annual meeting of the Acoustical Society of America in Columbus. Miller worked with UC faculty members Christy Holland in the department of radiology in the College of Medicine and Peter Disimile in the department of aerospace engineering and engineering mechanics.

The researchers used an experimental model made of transparent polyurethane tubing to simulate various shapes and sizes of blockages in arteries. Fluid was pumped through the tubing to simulate typical blood flow. Doppler ultrasound was used to track the amount of turbulence in the "blood" flow just past the blockage.

Turbulence results from fluid instabilities generated as blood flows past a blockage or "stenosis" in the arteries. The most intense turbulence results from the most severe blockages. Miller, Holland and Disimile used a second technique, laser Doppler anemometry, to verify the results from the Doppler ultrasound.

Those results indicate that the ultrasound technique can accurately predict the turbulence intensity. Quantitative measurements of the pressure drop across a series of stenoses indicate that the ultrasound technique can also detect early signs of atherosclerosis.

Ultrasound would also be safer than current methods which require either exposure to ionizing radiation (angiography) or the insertion of a pressure transducer within the artery itself.

"Doppler ultrasound offers quantitative, noninvasive clinical information," said Holland. "Peak turbulence intensity is a promising indicator of the severity of the stenosis and could aid in early detection of atherosclerosis."

The research has been supported by the Whitaker Foundation and a UC seed grant program in radiology. Holland and Disimile first began collaborating under UC's Biomedical Seed Grant Program which linked researchers in the College of Medicine with researchers in the College of Engineering.

Systemic hypertension is the most prevalent cardiovascular disorder in the United States, affecting over 50 million people. Hypertension leads to atherosclerosis and other forms of vascular disease by damaging blood vessel endothelium. Atherosclerosis -- characterized by the deposition of cholesterol, lipids and cellular debris in the lining of artery walls -- is responsible for the majority of cases of myocardial and cerebral infarction and is a principal cause of death in the U.S. and western Europe.