Radiation Dose in Angiography Similar to Other Procedures
Dose varies greatly with site and computed tomography system
09 feb 2009-- The radiation dose associated with cardiac computed tomography angiography (CCTA) is comparable to other diagnostic procedures, but varies depending on site and computed tomography system used, according to research published in the Feb. 4 issue of the Journal of the American Medical Association.
Jorg Hausleiter, M.D., from Klinik an der Technischen Universitat Munchen in Germany, and colleagues estimated the radiation dose associated with CCTA used to assess coronary artery disease in 1,965 patients.
The investigators found that the median dose-length product was 885 mGy x cm. This corresponded to an estimated radiation dose of 12 mSv, the equivalent of 600 chest x-rays, according to the study. Dose-length product varied greatly between the 50 study sites. Radiation dosage was affected by a number of factors, including patient weight, absence of stable sinus rhythm, scan length, 100 kV-tube voltage and sequential scanning, the researchers report. Reducing the dose by methods such as using a 100-kV scan protocol and the sequential scan mode did not affect image quality, they note.
The "study demonstrates that radiation dose of 12 mSv for CCTA is currently comparable with other diagnostic procedures (1.2 x the dose of an abdominal computed tomography study or 600 chest x-rays), but that this dose varies significantly between study sites and computed tomography systems," Hausleiter and colleagues conclude. "Additionally, the study demonstrates that radiation exposure can be reduced substantially by uniformly applying the currently available strategies for dose reduction, but these strategies are used infrequently."
Authors of the study and editorial report financial relationships with medical and pharmaceutical companies.