CT Angiography of Pulmonary Arteries to Detect Pulmonary Embolism: Improvement of Vascular Enhancement with Low Kilovoltage Settings

Abstract

At reduced radiation exposure, low kilovoltage scanning increases the percentage of central and peripheral pulmonary arteries that can be evaluated with CT angiography without a substantial decrease in image quality.

An education and training programme for radiological institutes: impact on the reduction of the CT radiation dose

“…-cerebral CT angiography [30,31] -pulmonary CT angiography [32][33][34] -aorto-iliac CT angiography [8,35,36] • Lowering of the tube voltage and/or tube current for non-contrast CT [37] • Reduction of the total number of imaging phases (e.g. split-bolus technique) [38,39] • Adjustment of image quality reference values of the automatic tube current modulation for oversized patients [40] • Reduction of the tube voltage and/or tube current for survey CT [41,42] • Positioning of the X-ray tube below the table for the survey CT (e.g.…”

Clinical value of dual-energy spectral imaging with adaptive statistical iterative reconstruction for reducing contrast medium dose in CT portal venography: in comparison with standard 120-kVp imaging protocol

“…Low-tube-voltage scanning has been used to reduce contrast medium dose in CTPA. 4,7 However, there is an inherent limitation with this technique, particularly when imaging the abdominal area where there is more attenuation or when attempting to evaluate non-vascular structures in patients with a higher BMI. 7 The recently introduced dual-energy spectral CT imaging mode has also been applied in clinical practice for either reducing contrast dose in CTPA 2 or improving image quality at the standard contrast dose level in CTPV.…”

“…4,7 However, there is an inherent limitation with this technique, particularly when imaging the abdominal area where there is more attenuation or when attempting to evaluate non-vascular structures in patients with a higher BMI. 7 The recently introduced dual-energy spectral CT imaging mode has also been applied in clinical practice for either reducing contrast dose in CTPA 2 or improving image quality at the standard contrast dose level in CTPV. 5 Using a single-source dualenergy system with rapid tube-voltage switching between 80 and 140 kVp, the dual-energy spectral CT imaging mode allows the acquisition of high-and low-kilovoltage peak projections simultaneously and produces 101 sets of virtual monochromatic images with photon energy levels from 40 keV to 140 keV.…”

CTPA for the diagnosis of acute pulmonary embolism during pregnancy

“…Whether this translates into a measurable increase in breast cancer risk is not yet known. Radiation dose with CTA, however, is strongly dependent on the chosen examination parameters: by optimizing scanning technique, for example by using low kVp settings [14], radiation dose can be reduced and vascular contrast can be increased.…”

“…In fact, this effect is so pronounced that reducing the tube voltage can more than compensate for the reduction of enhancement found in the present studies. Reducing the voltage from 140 kVp to 100 kVp was shown to increase average main pulmonary artery enhancement by 40% and increase enhancement for small arteries even more [14]. Most studies have used this increased enhancement to reduce radiation dose without affecting signal to noise, but in pregnant women the use of 80-100 kVpdepending on patient size-may help counteract the reduction of contrast enhancement seen in pregnancy.…”