Double-Low Dose Protocol of Computed Tomography Pulmonary Angiography (CTPA) in the Diagnosis of Pulmonary Embolism: A Feasible Approach for Reduction of Both Contrast Medium and Radiation Doses
DOI:
https://doi.org/10.17140/HROJ-4-139Keywords:
Computed tomography pulmonary angiography, Contrast medium, Optimization; Image quality, Pulmonary embolism, Radiation doseAbstract
This article discusses a hot topic on double low-dose protocol of computed tomography pulmonary
angiography (CTPA) in the diagnosis of pulmonary embolism, with a special focus
on a recent paper published in the British Journal of Radiology about the feasibility of this
technique. Three aspects will be discussed in this review: First, both kVp and contrast medium
can be reduced without affecting image quality when compared to the standard CTPA protocol;
second, a low-pitch protocol is comparable to the high-pitch spiral image acquisition with
similar image quality achieved, but at lower radiation dose; and finally, the double low-dose
CTPA protocol can achieve diagnostic images in patients with body mass index up to 35 kg/m2.
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