| Objective:To explore the application value of optimal preset and postset percentage of adaptive statistical iterative reconstruction-V(ASIR-V)in low-dose enhanced CT scan of upper abdomen in patients with decompensated cirrhosis.Materials and methodsFrom August 2018 to December 2018,a total 120 patients with decompensated cirrhosis who received dual-phase enhanced CT scan of upper abdomen in our hospital were selected.According to the random number table method,they were divided into A,B and C 3 groups,and the same ASIR-V reconstruction was carried out preset and postset 30%,40%and 50%respectively.Objective evaluation indexes of image quality include contrast-to-noise ratio(CNR)of liver,pancreas,spleen,portal vein and abdominal aorta.The subjective evaluation index of image quality is 5 points.The CT dose volume index(CTDIvol),dose length product(DLP)and effective dose(ED)of single enhancement phase were recorded.The objective evaluation index of image quality was compared with the radiation dose by one-way ANOVA,and the subjective score was compared by Kruskal-Wallis H test.Results1.CNR value:except for the liver parenchyma and portal vein of group C(50%ASIR-V)in portal vein phase were lower than that in other groups(q=2.104-3.398,P<0.05),and CNR values of parenchymal organs and aorta in other groups had little change(P<0.05).2.Image noise:with the increase of the forest ASIR-V ratio,the noise decreases slightly,but there is no obvious difference between groups.3.Radiation dose:compared with group B(40%ASIR-V)and group A(30%ASIR-V),group C(50%ASIR-V)had lower CTDIVol,DLP and ED values(P<0.001).Among them,compared with group A,the ED values of group C decreased by about 1.02(26.38%),while that of group B decreased by about 0.43(10.01%)mGy.4.Subjective evaluation:with the increase of ASIR-V preset percentage,the subjective score of plain scan images has little change,but the scores of arterial phase and portal vein phase have decreased,and the difference between group C and group A was obvious(Z=6.371-11.289,P<0.05).In group C,the contrast of parenchymal organs of portal vein phase images decreased,and wax-like changes appeared.Conclusion1.ASIR-V reconstruction technique was feasible for reducing radiation dose by abdominal contrast-enhanced scanning in patients with decompensated cirrhosis.2.For patients with decompensated cirrhosis,it was recommended to use 40%foreset and postset ASIR-V reconstruction,which can reduce the radiation dose and ensure the image quality.Objective1.To explore the application value of spectral combined with adaptive statistical iterative reconstruction-V(ASIR-V)in contrast-enhanced scanning of upper abdomen in patients with decompensated cirrhosis.2.Using spectral combined with ASIR-V reconstruction technology to select the best single-energy image showing the capability of substantive organs and hepatic vessels of patients with decompensated cirrhosis.Materials and methodsA prospective study was conducted on 100 patients with decompensated cirrhosis who planned to undergo enhanced scanning of upper abdomen from January 2019 to June 2019.They were divided into 120 kVp group and spetral group according to random number method,with 50 cases in each group.In the 120 kVp and spetral groups were both combined with 40%ASIR-V reconstruction scan for arterial and portal vein phases.The iodine content of contrast agent in 120 kVp group was 420mgI/kg,and that in spectral group was 320mgI/kg.At the same time,the monochromatic images of 40 keV,50keV,60keV and 70keVwere reconstructed from 40 to 60 keV in 10 keV intervals,respectively.The CT dose volume index(CTDIvol),dose length product(DLP)and effective dose(ED)of single phase enhancement were recorded and calculated in the 120 kVp group and spetral group.Objective evaluation of image quality including contrast-to-noise ratio(CNR)of liver,pancreas,spleen,portal vein and abdominal aorta.The subjective evaluation index of image quality are 5 points,and the branch of hepatic vessels are 4 points.The objective evaluation and radiation dose of the image were compared by one-way ANOVA,and the subjective scores of images was compared by Kruskal-Wallis H rank sum test.Results1.CT value:the spectral group(40-70keV)gradually decreased with the increase of monochromatic keV,70 keV group was lower than 120 kVp group,40 keV and 50 keV groups were higher than 120 kVp group(q=1.314-4.861,all P<0.05),while 60 keV group was equivalent to group 120 kVp.2.CNR value:in spectral groups,with the increase of keV,other indexes gradually decreased except the CNR value of liver in arterial phase;And 60 keV group was equivalent to that of group 120 kVp group(P<0.05),40 keV and 50 keV groups were higher than those of 120 kVp group,and 70 keV was significantly lower than that of 120 kVp group.The CNR value of abdominal aorta and portal vein,50 keV was equal to that of 120 kVp group.3.Image noise:in same phase(AP/PVP),the noise of spetral group was higher than that of 120 kVp group,and the noise of 40keV to 70keV groups gradually decreases with the increase of keV.The noise of 40 keV group and 50keV group were significantly higher than that of 120 kVp group(q=0.621-5.763,both P<0.05).However,there were no significant difference among 60 keV,70keV and 120 kVp groups.4.In the same phase,the overall image quality and noise score of the spectral group were slightly lower than those of the 120 kVp group,and the image quality subjective score of the spectral group(40-70 keV)increased with the increase of monochromatic keV.The image quality subjective score of 40 keV and 50 keV groups were lower than the other groups,while 50 keV had the same image quality as 120 kVp,and there were significant differences in the display of hepatic artery and portal vein branches among different groups(P<0.001).The 50 keV group showed better ability to display small branches of blood vessels,while 60 keV group was equivalent to 120 kVp group.5.Compared with the 120 kVp group,the CTDIvol,DLP and ED values of the spectral group were slightly higher,but there was no significant difference between the two groups.Compared with 120 kVp group(420 mgl/kg),the iodine content of contrast agent in spectral group(320 mgl/kg)decreased by about 24%(t=1.202,P<0.05),and the dose of contrast agent was reduced by about 20.39mL(23.67%).Conclusion1.The spectral combined with adaptive statistical iterative reconstruction-V(ASIR-V)can reduce the dose of contrast in patients with decompensated cirrhosis on the premise of ensuring the image quality.2.Upper abdominal contrast-enhanced scanning in patients with decompensated cirrhosis:60 keV monochromatic images have the same quality as 120 kVp image,and 50 keV monochromatic image have better ability to display hepatic vascular branches.Objective1.To compare the differences of clinical manifestations,laboratory examination and spectral CT imaging features of patients with decompensated cirrhosis with different survival and death outcomes.2.Based on the different clinical and imaging features between different survival and death outcome groups,the value of predictive spectral CT in predicting and evaluating the survival of patients with decompensated cirrhosis was predicted by single factor K-M survival analysis and multivariate COX survival analysis.Materials and methodsThe 118 patients with decompensatory cirrhosis underwent abdomen enhanced scanning were prospectively collected in our hospital from July 2019 to December 2019.All patients were performed three enhanced scans(arterial phase,portal phase and delayed phase)combined with 40%ASIR-V reconstruction.Non-ionic contrast agent with iodine content of 320 mgl/kg was adopted.The general situation,clinical manifestations and related laboratory test results of patients were recorded.The 50 keV monochromatic images of portal vein phase,60 keV monochromatic images of three-phase enhanced scanning and iodine-water image were obtained by post-processing workstation,respectively.Refer to the three-phase contrast-enhanced monochromatic images,record the amount of ascites and the presence or absence of esophageal and gastric varices and splenic shunt.At rest,the diameters of portal vein,splenic vein,esophageal vein and left gastric vein were measured by 50 keV monochromatic images.On the iodine-water image,the iodine concentration in ROI of right anterior lobe,right posterior lobe,left inner lobe and left outer lobe of liver were measured at the first level of hilum,and the iodine concentration in ROI of aorta was measured at the initial level of abdominal trunk of abdominal aorta.The standardized iodine concentration(NIC)of liver parenchyma and abdominal aorta were calculated in three phases.In addition,the extracellular volume fraction(fECV)was calculated by the delayed normalized iodine concentration of liver parenchyma.By the end of follow-up,the survival and death of all patients were counted,and the survival time without liver transplantation was recorded.The differences of clinical and imaging features between patients’s death and survival groups were compared.The diagnostic efficacy of the indicators with significant statistically differences in survival and death outcomes was evaluated by using the receiver working curve(ROC)and the area under the curve(AUC),and the continuous variables were classified by taking the point corresponding to the ROC curve closest to Youden’s index as the optimal diagnostic threshold.Finally,through univariate K-M survival analysis and multivariate COX survival analysis,the relevant indexes with clinical significance and statistical significance were analyzed to predict the risk factors of death risk in patients with decompensated cirrhosis.Results1.At the end of the follow-up,27 cases were died,91 cases were survived,and 3 cases of hepatocellular carcinoma were newly diagnosed.2.Child-Pugh C,hepatitis B and hepatitis C virus infection are the main types of patients with decompensated cirrhosis.Laboratory examination:There were significant differences in ALT,AST,albumin,total bilirubin,hematocrit,prothrombin time,Child-Pugh score and grade,MELD score between death and survival groups,and there were also significant differences in the types and composition ratios of complications(P<0.001).3.Comparison of imaging indexes between the two groups:the diameter of esophageal vein in the dead group was larger than that the surviving group;In the death group,ICLPVP and NICLPVP were lower than survival group,while ICLDP,NICLDP and fECV were higher than those in the survival group(all P<0.05).4.Univariate K-M survival analysis showed that there were significant differences in survival among different grades of Child-Pugh(P<0.001);When MELD score was≥18.5,total bilirubin was≥ 36.12 mmol/L,prothrombin time was≥15.45 s and albumin was<29.15 g/L,the survival rate of each group were lower than that of the corresponding group(all P<0.001).The survival rate of the group with lower NICLPVP and higher fECV value were lower than that of the corresponding groups(P=0.027 and 0.000).There were more than two types of complications in patients with decompensated cirrhosis,and the survival rate was low.5.Multivariate COX survival analysis showed that MELD score,two or more complications,albumin and fECV were independent risk factors for the death of decompensated cirrhosis.Conclusion1.MELD score,complications,albumin and fECV in patients with decompensated cirrhosis have significant differences among different outcomes,which can be used to evaluate the death risk of patients with decompensated cirrhosis.2.fECV calculated by spectral CT NICLDP was expected to be a noninvasive index to evaluate the survival and prognosis of patients with decompensated cirrhosis. |
PDF Full Text Request