Coronary CT angiography by modifying tube voltage and contrast medium concentration: Evaluation of image quality and radiation dose

Abstract

Background Currently, there is an increasing interest in noninvasive imaging of cardiovascular system such as computed tomography coronary angiography (CCTA). The risks of radiation‐induced cancer and contrast‐induced nephropathy (CIN) have always been regarded as concerns which increased demand for CCTA using reduced radiation dose and iodine intake. We aimed to evaluate the image quality and radiation dose of CCTA by modifying tube voltage and concentration of contrast media. Methods The present study includes 105 patients who underwent CCTA for clinical indications. Specific inclusion and exclusion criteria in terms of patient's weight, body mass index, calcium score, and stenting were used. First group of patients scanned by 120 kV and 370 mg I/mL contrast medium, compared with second and third groups for which scanning was performed using 100 kV and 370 mg I/mL and 100 kV and 300 mg I/mL, respectively. Image quality was evaluated both subjectively and objectively. The effective dose and iodine intake were also measured. Results Using low kV protocols led to radiation dose reduction up to 38% and applying low contrast medium concentration with consequent reduced iodine intake up to 21%. Moreover, there were significant differences in image quality of new scanning protocols. Conclusion Reduction in tube voltage with lowering of contrast medium concentration can reduce radiation dose and iodine intake with acceptable image quality.

Japanese Survey of Radiation Dose Associated With Coronary Computed Tomography Angiography ― 2013 Data From a Multicenter Registry in Daily Practice ―

“…A low tube voltage ≤100 kVp has been available in clinical practice along with the recently improved detector, image reconstruction technique, and tube designs with the capacity to generate high tube current at low tube voltage, resulting in radiation dose reduction with acceptable image quality. 24 The Society of Cardiovascular CT (SCCT) guidelines also recommend low tube voltage scanning, especially in non-obese patients (e.g., body weight ≤100 kg, BMI ≤30 kg/m 2 ) and in children. 7 In the present study, a low tube voltage ≤100 kVp was used in only 13% of eligible patients with BMI ≤30 kg/m 2 .…”

Artificial Intelligence Algorithm‐Based Computed Tomography Image in Assessment of Acute Renal Insufficiency of Patients Undergoing Percutaneous Coronary Intervention

“…Shear wave transform [ 18 ] is a new type of multiscale geometric analysis method, which is constructed by affine transformations such as scaling, shearing, and translation of the basic function, which embodies the geometric and mathematical characteristics of the function. In this study, the discrete nonseparable shear wave transform (DNST) was introduced as the core algorithm, and the inseparable shear wave generator can be expressed as follows: …”

“…e contrast agent iohexol was injected from the cubital vein at a flow rate of 2.5 mL/s, the scanning time of the arterial phase was 30 seconds, the scanning time of the parenchymal phase was 50 seconds, the scanning time of the delayed phase was 100 seconds, the reconstruction layer thickness was 1.5 mm, and the layer spacing was 1.5 mm. [18] is a new type of multiscale geometric analysis method, which is constructed by affine transformations such as scaling, shearing, and translation of the basic function, which embodies the geometric and mathematical characteristics of the function. In this study, the discrete nonseparable shear wave transform (DNST) was introduced as the core algorithm, and the inseparable shear wave generator can be expressed as follows:…”

Comparison of image quality and radiation dose using different pre-ASiR-V and post-ASiR-V levels in coronary computed tomography angiography

“…Because the radiation dose used in the CT examination is associated with the risk of cancer [1] , it is important to reduce the patient's radiation dose while retaining the image quality and diagnostic accuracy [2][3][4][5] . Traditional methods to reduce the radiation dose of CCTA include lowering the tube voltage and the use of tube current automatic modulation technology [6][7][8] . However, the reduction of tube voltage and tube current not only reduces the radiation dose, but it also increases the image noise and has a negative impact on image quality [9,10] .…”