Clinical Study For Parameters Optimized Low-dose CT Scanning Based On Site Specificity

In recent years, optimization of exposure parameters for low-dose CT scanninghas been attracting more and more attention from researchers and clinicians which hasbeen explored from the perspectives of reconstruction algorithm to design andoptimization of scan protocols to achieve the goal of lowering down patient’sradiation dose while assuring the quality of images for diagnosis. The purpose of thisresearch is to obtain optimized parameters of X-ray exposure for different sites withlow-dose CT scans based on body morphological features through a clinicalinvestigation.In this study, patient’s body thickness and circumference were used in theoptimization study. CT scan parameters were set up according to the two parametersof patients to be imaged to lower down the radiation dose. The image quality andradiation dose were used in the comparison between the low-dose scans andconventional scans to get the optimized exposure parameters for clinical applications.Phantom study was first conducted with different kV and mAs setups. Spatialresolution, contrast resolution, image homogeneity and noise were used in the imagequality evaluation and analysis according to the JJG1026一2007guideline. A clinicalstudy with270patients was followed. Head, thoracic and abdominal scans wereperformed respectively and optimized scan parameters for low-dose scans wereobtained. And then the optimized scan parameters were used for the experimentalgroup of60patients to further investigate the feasibility for routine clinical studies.The results have shown that radiation dose from CT scans can be reduced basedon patients’ body morphology without degrading the image quality. The dosereduction rates for head, thoracic and abdominal scans are28%,39%and27%,respectively. Clinical application of the new protocols will benefit patients and makecontributions to public health in general.