Phantom study on the influence of spectral CT monochromatic image based on deep learning image reconstruction algorithm
Objective To explore the effects of image reconstruction algorithm based on deep learning on the image quality of spectral CT monochromatic image.Methods Nine polypropylene test tubes with different diameters and concentrations of iodine contrast media and water and calcium solutions were placed in a cylindrical plastic phantom(QSP)with a diameter of 20 cm.Spectral CT ima-ging was performed on the phantom,and the 40～140 keV monochromatic image and energy spectrum curve were reconstructed using the energy spectrum analysis software.Three test tubes with concentrations of 3.75 mgI/mL(which simulated delayed phase or parenchymal organ enhancement),15 mgI/mL(which simulated abdominal aorta in arterial phase)and water(which simulated non enhancement substances used for image background such as plain scanning phase,cyst and muscle)were selected for the data measurement.CT values of monochromatic images(40 keV,70 keV and 100 keV)and image noise were measured in five groups of images,namely FBP,40％ASIR-V(routine clinical examination parameters)and True Fidelity(low,medium and high level),the signal-to-noise ratio(SNR)of each image was calculated,and the differences in the quality of the five groups of images were compared.Results There was no sig-nificant difference in CT values of 40 keV,70 keV,100 keV in low-concentration contrast agent(3.75 mgI/mL),high-concentration contrast agent(15.00 mg/mL)and water among five groups of images(P＞0.05).There was significant difference in image noise and SNR of single energy images(40 keV,70 keV and 100 keV)(P＜0.05).Compared with FBP and 40％ASIR-V,the image noise of True Fidelity™ was lower than that of FBP and 40％ASIR-V,and the image signal-to-noise ratio is improved(P＜0.05).True Fidelity™-DLIR-H had the lowest noise and the highest signal-to-noise ratio.Conclusion In spectral CT imaging,True Fidelity™has lower noise and higher signal-to-noise ratio than FBP and 40％ASIR-V in single-energy image.
万方数据
维普
