Résumé
Objective:To study the position of computed tomography(CT)slice of marker points of radiotherapy,which was determined by control scan(CS)method,on the application effect of patients with head and neck tumors who received radiotherapy.Methods:Based on Control Scan(CS)method,a calculator program of mark-point slice position was made,which was an enterprise WeChat program that could be used in calculating position and CT position scan of patients with head and neck tumor(slice thickness was 3mm).A total of 60 patients with head and neck tumor were selected,and the patients who underwent CT positioning scan by using CS method were divided into observation group,and patients who underwent CT position scan by using conventional method were divided into control group,with 30 cases in each group.The number of cases with three metal marker points displayed at the same slice,and the number of slices containing the CT images of marker point between the located CT scan were compared.Results:The number of patients in the observation group and the control group who showed three markers at the same level at the same time were respectively 26 cases and 13 cases,and observation group increased by 13 cases(43.4%)than control group,and the difference was significant(x2=12.382,P<0.05).The number of CT images with only 1 slice of observation group and control group were respectively 4 cases and 0 cases,which increased by 4 cases(13.3%)than the control group,and the difference was significant(x2=2.411,P<0.05).Conclusions:The CT localization scan of radiotherapy,which uses CS to assist patients with head and neck tumor,can precisely calculate and obtain the primary position of target of CT localization scan.It can take the images of 3 mental marker points of patient who receives radiotherapy to occur at the same CT slice as soon as possible,which has better application effect.It can effectively improve the convenience and work effectiveness of radiotherapy.
Résumé
Objective To delineate the normal stomach and thoracic stomach structure of patients with thoracic and abdominal tumor automatically using the AccuContour software based on deep learning in order to evaluate and compare the results. Methods Thirty-six patients with choracic and abdominal tumors were chosen for this study, and were divided into two groups. Group A included 18 patients with normal stomach, and group B included the other 18 patients undergoing esophageal carcinoma operation with thoracic stomach. The stomach structures were automatically delineated by the AccuContour software in the simulation CT series. Statistical analysis was carried out to data of the differences in volume, position and shape between the automatic and manual delineations, and data of the two kinds of stomach were compared. Results For group A, the differences in volume (ΔV%) between the automatic and manual delineations was (−1.82 ± 9.65)%, the total position difference (ΔL) was (0.51 ± 0.37) cm, the values of dice similarity coefficient (DSC) was 0.89 ± 0.04. There were significant differences in values of ΔV%、ΔL and DSC (P < 0.05). Conclusion The used version of AccuContour software in this study had a satisfactory result of automatic delineation of the normal stomach structure larger than certain volume, but could not delineate the thoracic stomach structures effectively for patients undergoing esophageal carcinoma operation.
Résumé
Objective To evaluate the constancy of CT numbers of SIEMENS Sensation Open CT-simulator by analyzing the CT numbers of seven materials obtained from quality assurance(QA)tests. Methods QA tests for SIEMENS Sensation Open CT-simulator were performed with the Catphan504 phantom monthly. The CT images were obtained using three scan protocols(HeadSeq,RT_Head,and RT_Abdomen)for the CTP404 module in the phantom. The DoseLab software was used to analyze the 72 CT images acquired from January 2014 to December 2015,and the CT numbers(Y)of seven materials were obtained. Statistical analysis was performed on the Y data. The mean,standard deviation,maximum, minimum,and range values of Y for seven materials were calculated in three scan protocols. Results The standard deviation values of air,polymethylpentene,low-density polyethylene,polystyrene,acrylic acid, polyoxymethylene resin(Delrin),and polytetrafluoroethylene(Teflon)were as follows:(1)HeadSeq:0.54, 0.60,0.82,0.58,0.75,0.66,and 1.83 HU;(2)RT_Head:0.08,0.69,0.86,0.66,0.80,0.89,and 2.49 HU;(3)RT_Abdomen:0.11,0.61,0.76,0.72,0.78,0.96,and 2.56 HU.According to the statistical data, the constancy of CT numbers of the SIEMENS Sensation Open CT-simulator was in good condition in two years. Conclusions The variation of CT numbers of Teflon is the biggest among the seven materials. The relative values of CT numbers between different scan protocols vary with the relative electron density of materials.