| Background and Purpose Computed tomographic (CT) angiography has become an important imaging technique in the evaluation of vascular lesion. In fact, CT angiography has demonstrated diagnostic superiority over conventional arteriography in several applications. CT angiographic examination is less invasive, less expensive, and capable of depicting important nonvascular abnormalities that otherwise would be missed with conventional angiography.With the recent introduction of multislice spiral CT scanners, multislice spiral CT angiography can be performed more efficiently (more quickly and with higher longitudinal spatial resolution) than was possible with single detector-row CT scanners. Currently, multislice spiral four-channel CT scanners acquire up to four channels of data simultaneously from interweaving helices. A single x-ray fan beam is used, and the length of the individual detector elements determines the section thickness. Table speeds of up to six times the nominal section thickness per gantry rotation (pitch, 6.0) are substantially faster than those of single-channel CT with a pitch of 2.0.To obtain the optimal reconstruction parameters of multislice spiral CT angiography (MSCTA) for celiac artery and its branches bycomparing the quality of the images obtained with three section overlaps.and assess its clinical applications in celiac artery. portal venous and living related liver transplantation(LRLT) donors. Materials and Methods (1) Forty-five patients recommended to abdominal reinforcement scan were randomly selected in this investigation. Images were obtained with 3.0mm x 2.5mm scan project, and the raw data was reconstructed with 3.0mm thick section and using 0%,50%and75% section overlap. Respectively, maximum intensity projection(MIP) and volume rendering(VR) were used for image reconstruction. Based on the marginal sharpness and the branch levels of the displayed vessels , a general evaluation of the image quality of the celiac artery and its branches was done by two experienced radiologists with double-blind method. A comparison of the image quality among three groups was made with statistic software of SPSS; (2) Forty-five patients recommended to abdominal reinforcement scan were randomly selected in this investigation. Images were obtained with 3.0mm x 2.5mm scan project, and the raw data was reconstructed with 3.0mm thick section and using 0%,50%and75% section overlap. Respectively, maximum intensity projection(MIP) and volume rendering(VR) were used for image reconstruction; (3) one hundred and ten patients recommended to abdominal enhancement scan were selected in this investigation. Images were obtained with 5.0 x 2.5mm scan project, theraw data was reconstructed with 3.0mm slice width and 1.5mm interval in the port vein phase. All patients were reconstructed in the mode of maxium intensity projection (MIP) and volume rendering (VR) ,curved planar reformation(CPR) was added in part cases; (4) 14 LRLT donors were evaluated with MSCT angiograms of hepatic blood vessel were generated by volume rendering(VR) and maximum intensity projection(MIP), curved planar reformation(CPR) was added in 3 patients.Results (1) By comparing the quality of the images obtained with 0%,50%,75% section overlap, images using 75% and 50% section overlap showed the same best quality (P>0.05), and better quality than that using 0% section overlap(P<0.05); (2) 36 cases were common celiac arteriography ; 6 cases were variant celiac arteriography; 22 cases were pathological celiac arteriography. The displaying rate of common hepatic artery, proper hepatic artery and its right and left branches,splenic artery, left gastric artery and superior gastroduodenal artery with VR and MIP was 100%(65/65), 100%(65/65), 80%(52/65), 76.9%(50/65), 100% (65/65), 73.9%(48/65), 96.9%(63/65), respectively; (3) MSCTP image could directly demonstrate the location and width of the portal and hepatic veins, detect the invasion and tumor thrombosis of portal vein, and show the range of collateral circulation and estimate its degree in p...
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