Automatic spectral imaging protocol selection combined with iterative reconstruction can enhance image quality and decrease radiation and contrast dosage in abdominal CT angiography.

PURPOSE: To investigate the effect of automatic spectral imaging protocol selection (ASIS) and adaptive statistical iterative reconstruction (ASIR) technology in reducing radiation and contrast dosage. METHODS: Sixty-four patients were randomly divided into two groups for abdominal computed tomography (CT): the experiment group with ASIS plus 50% ASIR and the control with 120 kVp voltage. RESULTS: The CT dose-index volume decreased by 23.68 and 23.57% and the dose-length product dropped by 25.59 and 18.45% in the arterial and portal venous phases, respectively, in the experiment than control group. The contrast dose was reduced by 16.86% in the experiment group. In the 55 keV + 50% ASIR group, the arterial contrast-to-noise ratio and scores were significantly (P < 0.05) higher than in the control group in the arterial phase while the portal contrast-to-noise ratio and scores were not significantly different between the two groups (P > 0.05). CONCLUSION: The ASIS technique plus 50% ASIR can enhance image quality of the abdominal structures while decreasing the radiation and contrast dosage compared with the conventional scan mode.

The optimal monochromatic spectral computed tomographic imaging plus adaptive statistical iterative reconstruction algorithm can improve the superior mesenteric vessel image quality.

OBJECTIVE: To investigate the effect of the optimal monochromatic spectral computed tomography (CT) plus adaptive statistical iterative reconstruction on the improvement of the image quality of the superior mesenteric artery and vein. MATERIALS AND METHODS: The gemstone spectral CT angiographic data of 25 patients were reconstructed in the following three groups: 70KeV, the optimal monochromatic imaging, and the optimal monochromatic plus 40%iterative reconstruction mode. The CT value, image noises (IN), background CT value and noises, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR) and image scores of the vessels and surrounding tissues were analyzed. RESULTS: In the 70KeV, the optimal monochromatic and the optimal monochromatic images plus 40% iterative reconstruction group, the mean scores of image quality were 3.86, 4.24 and 4.25 for the superior mesenteric artery and 3.46, 3.78 and 3.81 for the superior mesenteric vein, respectively. The image quality scores for the optimal monochromatic and the optimal monochromatic plus 40% iterative reconstruction groups were significantly greater than for the 70KeV group (P<0.05). The vascular CT value, image noise, background noise, CNR and SNR were significantly (P<0.001) greater in the optimal monochromatic and the optimal monochromatic images plus 40% iterative reconstruction group than in the 70KeV group. The optimal monochromatic plus 40% iterative reconstruction group had significantly (P<0.05) lower image and background noise but higher CNR and SNR than the other two groups. CONCLUSION: The optimal monochromatic imaging combined with 40% iterative reconstruction using low-contrast agent dosage and low injection rate can significantly improve the image quality of the superior mesenteric artery and vein.

[Retrospective analysis of renal echinococcosis confirmed by surgery and pathology: 3 cases].

A retrospective study was carried out to analyze 3 cases of renal echinococcosis confirmed by surgery and pathology in the hospital during 1999-2008. The patients were examined by 64-CT plain scan and multiple period enhancement scan. Among them, 2 were multi-daughter-cyst hydatid disease, and 1 appeared as solitary one. Two cases were once misdiagnosed as renal cyst and renal hamartoma, and the other was diagnosed correctly before operation. CT sign scanning combined with epidemiological information can make an accurate diagnosis for renal echinococcosis.