"Most equipment manufacturers recommend a sequential MDCT examination for the detection of coronary artery calcification, and we wanted to assess the reproducibility of these examinations," said Sandra S. Halliburton, PhD, a cardiac imaging scientist at Cleveland Clinic Foundation. Fifty-six patients were scanned twice using sequential MDCT, Dr. Halliburton said. The patients had no symptoms of coronary artery disease. "We compared the results of one scan to the other, and in most cases the results of the scans were similar enough that the patient would have been categorized with the same level of risk of developing coronary artery disease regardless of which scan was viewed," Dr. Halliburton said.
However, in seven patients, the results varied from one scan to the other and the patients would have been categorized as having different levels of risk depending on which scan was reviewed, she said. Most of these patients had a very small amount of calcium build-up and the differences in categorization likely would not have affected the Patients' treatment, Dr. Halliburton added.
This study indicates that sequential MDCT is "sufficient" for measuring coronary artery calcification. However, she added, more research needs to be done to see if there are even better techniques. Dr. Halliburton cautions that radiation dose needs to be considered; a technique that uses more radiation might mean more reproducible images, but the risk from the increased radiation exposure might outweigh the benefit, she said.
The study was done using 4-slice MDCT scanners; newer scanners are now being used in many places, Dr. Halliburton said.
The study was published in the February 2005 issue of the American Journal of Roentgenology.
A PDF of the full study is available upon request to reporters.
Journal
American Journal of Roentgenology