Reduced Tube Voltage Linked to Less Radiation Exposure
In coronary CT angiography, lower tube voltage also preserves image quality in non-obese patients
THURSDAY, April 9 (HealthDay News) -- Lower tube voltage was linked to reduced radiation exposure in patients undergoing coronary dual-source computed tomography (CT) angiography, according to research published in the April issue of the American Journal of Roentgenology.
Tobias Pflederer, M.D., of the University of Erlangen in Germany, and colleagues analyzed data from 100 patients who underwent coronary dual-source CT angiography with either the traditional 120 kV or 100 kV. All patients had a body weight of 85 kilograms or less.
Patients in the 100-kV group had significantly lower mean radiation exposure (7.8 mSv and volume CT dose index 28.6 mGy) compared to the 120-kV group (12.7 mSv and volume CT dose index 47.8 mGy), the investigators found. Image quality was comparable in both groups (mean image quality scores 2.6 versus 2.7, respectively). Vessel-based scores were also similar, the authors note.
"In conclusion, the use of a coronary CT angiography protocol with reduced tube voltage leads to a significant reduction of radiation exposure while image quality is preserved in non-obese patients. Other mechanisms, such as the use of prospectively instead of retrospectively gated MDCT and a further reduction of tube current during ECG dose modulation might lead to additional reductions in radiation dose. These mechanisms should be further investigated to minimize radiation exposure while preserving an adequate and diagnostic image quality in coronary CT angiography," Pflederer and colleagues write.