Kevin Johnson, Ph.D., a University of Florida College of Medicine-Jacksonville assistant professor of radiology, was awarded a $375,000 New Investigator Research Grant from the Florida Department of Health and the James and Esther King Biomedical Research Program.
The three-year grant is designed to support new researchers in the areas of prevention, diagnosis, treatment and cure of tobacco-related diseases. Smoking and other tobacco use are significant risk factors for heart and cardiovascular disease. Johnson’s investigation is based on the use of new dual energy CT technology at Shands Jacksonville.
The basis for his study includes a series of assessments. Calcium scoring is a simple, non-invasive screening procedure that takes CT images of the heart and identifies plaques in the blood vessel made of calcium. If a patient has a large amount of calcified plaque – a high “calcium score”- that individual is considered to be at higher risk for other, more dangerous areas of disease in the coronary arteries that may lead to blockages and heart attacks. In this situation, a CT coronary angiography scan may be performed.
Angiography scans use a contrast agent injected into a blood vessel in the patient’s arm so that the coronary arteries can be seen in the CT images. These scans will show if an artery is narrowed or blocked by plaque.
Perfused blood volume imaging provides even more information by looking at the amount of blood inside the muscle tissue. Even if an artery is blocked or narrowed, the muscle tissue of the heart around that artery may still be getting enough blood and oxygen from a nearby artery. Conversely, a patient could have small vessel disease that may not be visible in an angiography scan but still limits the blood flow. Perfused blood volume imaging can now be done on Shands Jacksonville’s new dual energy CT scanner.
Because the angiography and perfused blood volume scans both use contrast agent while the calcium scoring does not, these have been done as two or three separate scans. The proposed research in the awarded grant is to perform the calcium scoring scan with contrast agent using techniques that are unique to the new dual energy CT scanner and isolate the calcium signal in the images. This would reduce the total number of scans and decrease the amount of X-ray radiation the patient receives from the studies.