Double-Low technique: The optimal protocol for Chest CT, Abdomen CT, CT Coronary Angiography and CT Pulmonary Angiography

Kalliopi Mandourari, Ioanna Karachristou


The main goal in radiology is to obtain high quality images with the least radiation dose to the patient. In order to be achieved diagnostically acceptable Computed Tomography (CT) images with a minimum dose of radiation and contrast media (CM) many approaches have been developed. “Double-Low” technique is an encouraging approach which refers to the combination of low tube voltage and low CM load using an iterative reconstruction algorithm (IR). The purpose of this study is to compare the most recently proposed approaches on “double-low” technique to the standard protocols and determine the optimum protocol for each anatomical region. Regarding the abdominal CT a reduction in the CTDIvol and CM load of up to 20-30% and 22.9-40% respectively was reported. While, as for the chest CT a reduction in the effective and CM dose of up to 25-32% and 23-30% respectively was revealed. Moreover, in the CT Coronary Angiography (CTCA) the results showed a reduction of the effective and CM dose of up to 13.5-94.8% and 20-60.7% respectively. Finally, with respect to the CT Pulmonary Angiography (CTPA) a reduction of the effective and CM dose of up to 27-63.6% and 22.9-58.3% respectively was mentioned.


radiation; contrast medium; computed tomography

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