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Humans ; COVID-19 ; SARS-CoV-2 ; Mental Health ; Cohort Studies ; Quality of Life ; China/epidemiology* ; Health Personnel ; Hospitals ; Lung

Objective:To investigate the feasibility and safety of laparoscopic liver tumor resection in children.Methods:The clinical data of 6 children undergoing laparoscopic liver tumor resection from June 2018 to March 2020 in the Affiliated Tumor Hospital, Zhengzhou University were retrospectively analyzed.Results:There were 4 males and 2 females among the 6 cases, with the average age of (7±2)years.All the children were admitted to the hospital with a liver occupying examination due to physical discomfort.Preoperative diagnosis: 3 cases of hepatoblastoma, 1 case of primary liver cancer, 1 case of hepatic adenoma and 1 case of hepatic nodular hyperplasia.All the children successfully completed laparoscopic liver tumor resection without conversion to open surgery.Among them, 3 children obtained left hemihepatectomy, 1 child underwent hepatic left lobectomy, 1 child was given VI hepatectomy, and 1 child accepted hepatic caudate lobectomy.The operation time was(90±9)min, and the average intraoperative blood loss was (83±26) mL.All children had no blood transfusion during or after operation.There were no bleeding, bile leakage, infection and liver failure after operation.All children had no gastric tube before surgery and the fluid diet was given on the first day after operation, and the postoperative median hospital stay was 4(3-5) days.The pathology were consis-tent with the preoperative diagnosis, and the resections were all radical operation resections.The follow-up period was from 2 to 23 months, and all the children recovered well and no recurrence was observed.Conclusions:Laparoscopic liver tumor resection in children is safe and feasible, which can minimize trauma, reduce intraoperative bleeding and shorten the hospital stay without increasing the incidence of postoperative complications.Laparoscopic liver tumor resection in children has certain advantages.

Objective:To compare the clinical outcomes between the new cold-circulation bipolar radiofrequency assisted versus Habib-4X bipolar radiofrequency assisted open hemihepatectomy.Methods:A retrospective study was conducted on 45 patients who underwent bipolar radiofrequency assisted open hemihepatectomy at the Affiliated Tumor Hospital of Zhengzhou University from October 2016 to January 2020. There were 28 males and 17 females, with an average age of 52.2 years. These patients were divided into the experimental group ( n=20) who underwent the new cold-circulation bipolar radiofrequency assisted open liver resection, and the control group ( n=25) who underwent the Habib 4X bipolar radiofrequency assisted open liver resection. The postoperative alanine aminotransferase (ALT), postoperative aspartate aminotransferase (AST), liver coagulative necrosis plane width, speed of liver parenchymal transection, electrode needle carbonization rate, and postoperative complications were compared between groups. Results:In the experimental group, the speed of liver parenchymal transection was (5.0±2.0) cm 2/min, the width of the coagulative necrosis plane was (1.36±0.21) cm, the AST on the first postoperative day was (177.0±79.3) U/L, the ALT on the first postoperative day was (200.2±78.5) U/L, and the electrode needle tip carbonization rate was 20.0% (4/20). These figures were significantly better than the control group with (3.6±1.7) cm 2/min, (1.93±0.16) cm, (233.2±66.6) U/L, (249.2±62.9) U/L, and 56.0% (14/25), respectively (all P<0.05). The postoperative complication rate was 15.0% (3/20) in the experimental group and 24.0% (6/25) in the control group ( P>0.05). Conclusion:Cold-circulation bipolar radiofrequency assisted hemihepatectomy was safe and feasible. It had the advantages of rapid transection of liver parenchyma, a low electrode tip carbonization rate, and a more accurate coagulation range.

Objective:To investigate the application value of different surgical approaches in the radical resection of Siewert type Ⅱ adenocarcinoma of esophagogastric junction (AEG).Methods:The retrospective cohort study was conducted. The clinicopathological data of 84 patients with Siewert Ⅱ AEG who were admitted to the Fourth Hospital of Hebei Medical University from March 2018 to March 2019 were collected. There were 65 males and 19 females, aged from 43 to 82 years, with a median age of 66 years. Of 84 patients, 24 cases undergoing radical resection of AEG via abdominal transhiatal approach (TH) were allocated into TH group, 32 cases undergoing radical resection of AEG via left thoracic approach (Sweet) were allocated into Sweet group, 28 cases undergoing radical resection of AEG via right thoracoabdominal approach (RTA) were allocated into RTA group. Observation indicators: (1) surgical and postoperative conditions of Siewert Ⅱ AEG patients in the 3 groups; (2) postoperative complications of Siewert Ⅱ AEG patients in the 3 groups. (3) Follow-up. Follow-up using outpatient examination and telephone interview was conducted to detect postoperative life quality, tumor recurrence and survival of patients up to March 2020. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was analyzed using the ANOVA. Measurement data with skewed distribution were represented as M (range), comparison among multiple groups was analyzed using the Kruskal-Wallis H test, and comparison between two groups was analyzed using the Dunn Bonferroni test. Count data were described as absolute numbers, and comparison between groups was analyzed using the chi-square test. Results:(1) Surgical and postoperative conditions of Siewert Ⅱ AEG patients in the 3 groups: the operation time for Siewert type Ⅱ AEG patients in TH group, Sweet group and RTA group were 216 minutes (range, 190-230 minutes), 174 minutes (range, 152-185 minutes) and 295 minutes (range, 261-337 minutes), respectively, showing a significant difference among the 3 groups ( H=57.977, P<0.05). There were significant differences between the TH group and the Sweet group, between the TH group and the RTA group, respectively ( P<0.05). There was also a significant difference between the Sweet group and the RTA group ( P<0.05). The volume of intraoperative blood loss for Siewert type Ⅱ AEG patients in TH group, Sweet group and RTA group were 150 mL (range, 100-163 mL), 150 mL (range, 150-200 mL) and 200 mL (range, 150-263 mL), respectively, showing a significant difference among the 3 groups ( H=11.097, P<0.05). There was no significant difference between the TH group and the Sweet group ( P>0.05). There were significant differences between the TH group and the RTA group, between the Sweet group and the RTA group, respectively ( P<0.05). The number of lymph node dissected for Siewert type Ⅱ AEG patients in TH group, Sweet group and RTA group were 15 (range, 9-19), 17 (range, 10-21) and 30 (range, 24-40), respectively, showing a significant difference among the 3 groups ( H=29.775, P<0.05). There was no significant difference between the TH group and the Sweet group ( P>0.05). There were significant differences between the TH group and the RTA group, between the Sweet group and the RTA group, respectively ( P<0.05). The number of thoracic lymph node dissected for Siewert type Ⅱ AEG patients in TH group, Sweet group and RTA group were 0, 2 (range, 1-3) and 6 (range, 3-9), respec-tively, showing a significant difference among the 3 groups ( H=48.140, P<0.05). There were significant differences between the TH group and the Sweet group, between the TH group and the RTA group, respectively ( P<0.05). There was also a significant difference between the Sweet group and the RTA group ( P<0.05). The number of abdominal lymph node dissected for Siewert type Ⅱ AEG patients in TH group, Sweet group and RTA group were 15 (range, 9-19), 12 (range, 8-19), and 24 (range, 17-35), respectively, showing a significant difference among the 3 groups ( H=18.149, P<0.05). There was no significant difference between the TH group and the Sweet group ( P>0.05). There were significant differences between the TH group and the RTA group, between the Sweet group and the RTA group, respectively ( P<0.05). The number of positive lymph node for Siewert type Ⅱ AEG patients in TH group, Sweet group and RTA group were 2 (range, 0-3), 0 (range, 0-3), and 5 (range, 1-6), respectively, showing a significant difference among the 3 groups ( H=7.729, P<0.05). There was no significant difference between the TH group and the Sweet group, between the TH group and the RTA group, respectively ( P>0.05). There was a significant difference between the Sweet group and the RTA group ( P<0.05). The time to postoperative first flatus of Siewert type Ⅱ AEG patients in TH group, Sweet group and RTA group were 3 days (range, 3-4 days), 3 days (range, 3-4 days), and 4 days (range, 3-5 days), respectively, showing no significant difference among the 3 groups ( H=3.125, P>0.05). The duration of postoperative hospital stay for Siewert type Ⅱ AEG patients in TH group, Sweet group and RTA group were 16 days (range, 14-17 days), 14 days (range, 12-15 days), and 19 days (range, 18-21 days), respectively, showing a significant difference among the 3 groups ( H=35.244, P<0.05). There was no significant difference between the TH group and the Sweet group ( P>0.05). There were significant differences between the TH group and the RTA group, between the Sweet group and the RTA group, respectively ( P<0.05). (2) Postoperative complications of Siewert Ⅱ AEG patients in the 3 groups: there were 6, 6, 11 Siewert type Ⅱ AEG patients of the TH group, Sweet group and RTA group with cardiopulmonary complication, respectively, 1, 1, 2 patients with anastomotic leakage and 1, 0, 1 patients with AEG-related death, showing no significant difference in the above indicators among the 3 groups ( χ2=3.263, 0.754, 1.595, P>0.05). (3) Follow-up: 78 of 84 Siewert type Ⅱ AEG patients were followed up for 9.0 to 24.0 months, with a median follow-up time of 16.6 months. Cases with reduced respiratory function at postoperative 3 months for the TH group, Sweet group and RTA group were 4, 3, 5, respectively. Cases with gastroesophageal reflux at postoperative 3 months for the 3 groups were 3, 6, 7, respectively. Cases with weight loss at post-operative 3 months for the 3 groups were 3, 2, 4, respectively. There was no significant difference in the above indicators among the 3 groups ( χ2=1.009, 1.107, 1.112, P>0.05). Cases tumor recurrence and metastasis in the TH group, Sweet group and RTA group were 5, 7, 4, cases who survived at postoperative 1 year in the 3 groups were 19, 24, 25, respectively. There was no significant difference in the above indicators among the 3 groups ( χ2=0.897, 1.261, P>0.05). Conclusion:RTA appiled in Siewert type Ⅱ AEG patients has a longer postoperative operation time, increased intra-operative blood loss and longer hospital stay, while has better advantages in lymph node dissection.

Objective:To investigate the features of median arcuate ligament syndrome (MALS) in computed tomography angiography (CTA).Methods:The retrospective and descriptive study was conducted. The clinical and imaging data of 56 patients with MALS who were admitted to Ruijin Hospital, Shanghai JiaoTong University School of Medicine from November 2019 to October 2020 were collected. There were 30 males and 26 females, aged from 19 to 78 years, with a median age of 54 years. All 56 patients underwent CTA. Observation indicators: (1) CTA examination; (2) correlation analysis; (3) surgical situations. Measurement data with normal distribution were represented as Mean± SD. Count data were described as absolute numbers or percentages. Spearman correlation analysis with test level of 0.05 was used to analyze the correlation between celiac trunk stenosis and the distance between the original location of celiac trunk and original location of superior mesenteric artery and the minimum distance of celiac trunk and superior mesenteric artery. Results:(1) CTA examination. ① Celiac trunk stenosis: results of cross sectional examina-tion of CTA showed that of 56 patients, there were 2 cases of celiac trunk occlusion, 10 cases of severe stenosis, 9 cases of moderate stenosis and 35 cases of mild stenosis. Results of sagittal examination of CTA showed that of 56 patients, there were 2 cases of celiac trunk occlusion, 21 cases of severe stenosis, 15 cases of moderate stenosis and 18 cases of mild stenosis. ② Examination of patients with different degree of vascular stenosis: according to the results of sagittal examination of CTA, the 2 cases with celiac trunk occlusion were negative for aneurysms, aortic dissection or vascular variations but positive for compensated varix of the anterior and posterior pancreatico-duodenal arches. Of the 21 cases with celiac trunk severe stenosis, 2 cases were positive for aneurysms, 1 case was positive for aortic dissection, 7 cases were positive for compensated varix of the anterior and posterior pancreaticoduodenal arches, 8 cases were positive for collateral circula-tions of anterior and posterior pancreaticoduodenal archs and 8 cases were positive for vascular variation. Of the 15 cases with celiac trunk moderate stenosis, 2 cases were positive for aneurysms, 3 cases were positive for aortic dissection, 2 cases were positive for compensated varix of the anterior and posterior pancreaticoduodenal arches, 4 cases were positive for collateral circulations of anterior and posterior pancreaticoduodenal archs and 7 cases were positive for vascular variation. Of the 18 cases with celiac trunk mild stenosis, 1 case was positive for aneurysms, 2 cases were positive for aortic dissection, 7 cases were positive for collateral circulations of the anterior and posterior pancreaticoduodenal arches, 6 cases were positive for vascular variation. All 56 patients were negative for ischemia of liver, spleen and stomach. ③ Original location of celiac trunk: of 56 patients, there were 43 cases had celiac trunk originated horizontally from the lower edge of T12 vertebral body, 2 cases had celiac trunk originated from the middle of T12 vertebral body, 1 case had celiac trunk originated from the upper part of T12 vertebral body, 7 cases had celiac trunk originated from the upper part of L1 vertebral body, 1 case had celiac trunk originated from the middle of L1 vertebral body and 2 cases had occluding celiac trunk. (2) Correlation analysis: results of sagittal observation on CTA examination showed the distance between the original location of celiac trunk and original location of superior mesenteric artery of the 56 patients was (6.0±4.0) mm. The distance between the original location of celiac trunk and original location of superior mesenteric artery of patients with celiac trunk mild, moderate or severe stenosis were (6.2±2.8)mm, (8.1±4.4)mm and (5.3±3.2)mm respectively. There were 23 cases of the 56 patients had the distance between the original location of celiac trunk and original location of superior mesenteric artery <5 mm. Results of correlation analysis showed that the degree of celiac trunk stenosis was not related to the distance between the original location of celiac trunk and original location of superior mesenteric artery ( r=?0.205, P>0.05). Results of sagittal observation on CTA examination showed the shortest distance between celiac trunk and superior mesenteric artery of the 56 patients was (3.8±2.4)mm. The shortest distance between celiac trunk and superior mesenteric artery of patients with celiac trunk mild, moderate or severe stenosis were (4.2±2.0)mm, (4.4±3.3)mm and (3.0±1.9)mm, respectively. There were 45 cases of the 56 patients had the shortest distance between celiac trunk and superior mesenteric artery <5 mm. Results of correlation analysis showed that the degree of celiac trunk stenosis was not related to the shortest distance between celiac trunk and superior mesenteric artery ( r=?0.249, P>0.05). (3) Surgical situations: of 56 patients, 2 cases were positive for clinical symptoms of abdominal pain, 54 cases were negative for clinical symptoms, 4 cases under-went surgical treatment and 52 cases not underwent surgical treatment. Of the 4 cases undergoing surgical treatment, 2 cases with abdominal pain were diagnosed as MALS by upper abdominal CTA. Celiac trunk of the 2 cases were severe stenosis and stents implantation under celiac arteriography were performed. Results of postoperative CTA showed celiac trunk was negative for obvious stenosis. The other 2 cases who were negative for clinical symptoms of MALS were planed to pancreaticoduo-denectomy for pancreatic head tumor. Results of preoperative CTA showed severe stenosis of celiac trunk and arterial bypass grafting was performed for the 2 cases during pancreaticoduodenectomy to alleviate liver ischemia caused by gastroduodenal artery ligation which would avoid the incidence of postoperative MALS associated complications. Result of postoperative CTA three-dimensional reconstruction showed the bypass vessel was unobstructed. Conclusion:Based on sagittal result of CTA examination, the stenosis of celiac trunk, the anatomical relationship between celiac trunk and arcuate ligament and the original location of celiac trunk of MALS patients can be evaluated.

Objective:To investigate the clinical value of iodine density map and low keV virtual monoenergetic images (VMI) derived from dual-layer spectral detector CT (DLCT) for the pancreatic neuroendocrine tumors (pNETs) detection.Methods:From January to June 2019, data of 23 pathologically confirmed patients of pNETs were retrospectively analyzed. All of the patients underwent pancreas enhanced DLCT scanning within 1 week before surgery. The conventional polyenergetic images (PI), iodine density map and 40, 50, 60, 70 keV VMI were generated. One resident radiologist with 3 years’ experience and one senior radiologist with over 10 years’ experience interpreted the images for the lesion detection independently using the following image series: PI, VMI (40-70 keV), PI combined with iodine density map. Lesion detection rates were recorded and compared among different image series. The CT value and noise of lesion, normal pancreatic parenchyma, and abdominal subcutaneous fat were measured in PI and VMI in both arterial and portal vein phases. The contrast-to-noise ratio (CNR) of lesion was calculated. The CT value of lesion and normal pancreatic parenchyma, CNR of lesion, and image noise were compared using repeated one-way ANOVA test. Subjective image quality was assessed with a 5-point scale and compared with Friedman test.Results:A total of 26 lesions were confirmed from 23 patients. For resident radiologist and senior radiologist, the detection rates of pNETs lesion using PI were 76.9% (20/26) and 84.6% (22/26) respectively, and both improved to 92.3% (24/26) using image series of 40 and 50 keV VMI. For senior radiologist, the pNETs lesion detection rate was further improved to 96.2% (25/26) using image series of PI with iodine map. The CT value of lesion and normal pancreatic parenchyma, CNR, and image noise had statistical differences among PI and VMI (40-70 keV) in both arterial and portal vein phase ( P<0.001). The mean CT attenuation and CNR of lesion in VMI increased significantly as the energy level decreased.The CNR of lesion in all VMI (40-70 keV) was significantly higher than that in PI. The median of subjective scores of image quality in PI and VMI (40-70 keV) were 3, 3, 4, 4, and 5 respectively, and the difference was statistically significant (χ2=66.393, P<0.001). Conclusions:The low keV VMI derived from DLCT can increase the CT value and CNR of pNETs, and the lesion detection rate can be improved combined with iodine density map. The CNR of pNETs is the highest in 40 keV VMI, and image noise is still lower than that of PI, so 40 keV VMI is recommended for clinical application.

Objective:To explore the image quality of 40 keV virtual monoenergetic images (VMI) derived from dual-layer spectral detector CT （DLCT） pancreas dynamic enhanced scanning and its optimal window setting.Methods:From January to July 2019, 28 patients who underwent pancreas enhanced DLCT scan within one week before surgery and pathologically confirmed of pancreatic neuroendocrine tumors (pNETs) were retrospectively enrolled. Conventional polyenergetic images (PI) and 40 keV virtual monoenergetic images （VMI 40 keV） were generated after scanning.CT value of normal pancreatic parenchyma, lesion, abdominal subcutaneous fat, abdominal aorta and portal vein were measured in PI and VMI 40 keV. The contrast-to-noise ratio (CNR) of the pNETs lesion was calculated. All these objective results were compared between VMI 40 keV and PI using paired ttest. Individual window settings （W-Ind, including window width and window level） of VMI 40 keVwere recorded. Calculated window settings （W-Calc） were mathematically calculated via regression analysis and optimized window settings （W-Opt） were obtained.Subjective image quality was assessed with a 5-point scale and compared among VMI 40 keV with different window settings (W-Std, W-Ind, W-Calc and W-Opt) using Friedman test, and compared PI with standard abdominal window setting (W-Std) and VMI 40keV with W-Opt settings using Wilcoxon test.The maximum diameter of lesion was measured and compared with one-way ANOVA analysis among PI and VMI 40 keV with different windows settings. Results:For VMI 40 keV in both arterial phase and portal vein phase, the CT attenuation [(464.0±136.7), (375.4±79.2) HU] of pNETs lesion were statistically significantly higher than those in PI [（168.8±38.0), (140.5±23.5) HU] （ t=-16.107,-22.225, P<0.001）, CNR （16.5±11.1, 10.9±6.1） were also statistically significantly higher than those in PI （4.5±2.9, 3.0±1.9） （ t=-7.838, -9.781， P<0.001）,while with lower image noise in VMI 40 keV[（11.8±1.5),(11.8±1.4) HU] than PI （13.1±1.5,12.9±1.3 HU）（ t=6.356,3.891， P<0.001）. The subjective score for PI with W-Std and VMI 40 keV with W-Std, W-Ind, W-Calc, W-Opt in arterial phase were 4（1）, 1（0）, 5（0）, 5（0.75）, 5（1）, and which in portal vein phase were 3.5（1）, 1（0）, 5（0）, 5（0）, 5（1）.The subjective score of VMI 40 keV with different window settings had statistical differences （χ 2=76.143,76.000， P<0.001）. Compared to the image quality of PI with W-Std settings, VMI 40 keV with W-Opt settings have higher objective score （ Z=4.685, 4.235， P<0.001）. The maximum diameter of lesion has no statistical difference among PI and VMI 40 keV with different window settings （ F=0.008, 0.004， P>0.999） in both arterial phase and portal vein phase. Conclusions:The VMI 40 keV in pancreas dynamic enhancement scanning derived from dual-layer spectral detector CT have higher image quality than PI. Due to changes of CT value of tissue in VMI 40 keV, it is recommended to optimize window settings （window width/window level， 880/230 HU for arterial phase and 840/260 HU for portal vein phase） to obtain the best image quality.

Hepatocellular carcinoma (HCC) is mostly treated by surgery combined with interventional therapy, chemotherapy, radiotherapy and local treatment. However, it often relapses after the operation. And the prognosis of advanced patients is poor, and the effective rate of chemotherapy and molecular targeted therapy is low. Recent studies indicated that the occurrence and progress of HCC are closely related to the immune function of the body. Immunotherapy, as a new type of tumor therapy, has drawn much attention. By improving the immunogenicity of tumor cells and the killing sensitivity of effector cells, it stimulates the immune function of the body, prolongs the progression-free survival time and the overall survival time of patients, and becomes an integral part of the comprehensive treatment of liver cancer. This article reviewd the progress in immunotherapy of HCC in the recent years.

Objective:To study the safety and efficacy of liquid isolation assisted technology in ultrasound-guided percutaneous radiofrequency ablation for hepatocellular carcinoma adjacent to liver surfaces.Methods:A retrospective study was conducted on 246 patients with hepatocellular carcinoma near liver surfaces treated by radiofrequency ablation from November 2016 to November 2019 at the Department of Hepatobiliary and Pancreatic Surgery, Affiliated Tumor Hospital of Zhengzhou University. There were 182 males and 64 females, aged (56.7±9.2) years. The patients were divided into the liquid isolation group with liquid isolation assisted technology for radiofrequency ablation ( n=131) and the conventional treatment group with conventional radiofrequency ablation ( n=115). The complication, one-time complete ablation and progression-free survival rates were compared between the two groups. Results:The incidence of intraoperative complications in the liquid isolation group was 21.4% (28/131), versus 20.9% (24/115) in the conventional treatment group. There was no significant difference between the two groups ( P>0.05). The incidence of postoperative complications in the liquid isolation group was 20.6% (27/131), which was significantly lower than that in the conventional treatment group 33.9% (39/115) ( P<0.05). The incidence of postoperative pain in the liquid isolation group was 6.1% (8/131), which was significantly lower than that in the conventional treatment group 15.7% (18/115) ( P<0.05). For the 131 patients in the liquid isolation group, there were 183 tumors near to liver surfaces. For the 115 patients in the conventional treatment group, there were 142 lesions near to liver surfaces. The one-time complete ablation rate in the liquid isolation group was 94.0% (172/183), which was significantly higher than the 75.4% (107/142) in the conventional treatment group ( P<0.05). The progression-free survival rate in the liquid isolation group was significantly better than that in the conventional treatment group ( P<0.05). Conclusion:The liquid isolation technique increased the one-time complete ablation rate of liver cancer adjacent to liver surfaces, reduced the incidence of postoperative complications and improved prognosis.

Objective To explore the feasibility of the virtual non-contrast images derived from dual-layer spectral detector CT (SDCT) substitute for true non-contrast images.Methods From July 2017 to September 2017,40 patients under-went pre-and arterial-venous dual-phase post-contrast abdominal imagining on a SDCT in Shanghai Jiaotong University School of Medicine Affiliated Ruijin Hospital.The images were retrospectively analyzed.The arterial VNC images (VNC-a) and venous VNC images (VNC-v)were derived from spectral based image (SBI) datasets of arterial and portal venous phase using a dedicated software respectively.Then mean CT attenuation,mean image noise,signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were compared with one-way ANOVA analysis among TNC,VNC-a,VNC-v images in liver,spleen,pancreas,abdominal aorta,inferior vena cava,psoas muscle,L4 vertebra and perirenal fat.And Bland-Altman plots was used to analyze the CT attenuation equivalence between TNC and VNC.Subjective image quality was assessed with a 5-point scale and compared with Friedman H test.The dose length product (DLP) of pre-and post-contrast scans were recorded.Results The CT attenuation of abdominal aorta,perirenal fat,L4.vertebra among three kinds of images had significant differences (P＜0.05)which overestimated the CT attenuation of perirenal fat and underestimated CT attenuation of abdominal aorta and vertebra compared to TNC,VNC.Except for pancreas,the image noise of all other tissues among three kinds of images had significant differences,images noise of VNC images were lower than TNC images (P＜0.05).The SNR of liver,spleen,psoas muscle and inferior vena cava and CNR of pancreas,abdominal aorta,inferior vena cava,L4 vertebra and perirenal fat were statistically significant among the three images (P＜0.05).Except for vertebra and perirenal fat,good equivalence between VNC and TNC images were observed in all relevant tissues with Bland-Altman analysis.Image quality subjective scoring of TNC,VNC-a,and VNC-v were 5.00(1.00),5.00(0.75),5.00(1.00) respectively which had no significant differences (P=0.20).The DLP of TNC,arterial and venous phase scan were (255.2±62.0),(258.9±62.9),(252.0±61.2)mGy·cm,and the total DLP of dual-phase contrast enhanced scan was (766.2± 185.3) mGy· cm.The DLP of TNC accounted for 33.3％(255.2/766.2) of the total DLP,and effective dose of TNC was (3.83±0.90)mSv.Conclusions CT attenuation in VNC image which exhibited lower image noise was identical to TNC images in the majority of abdomen tissues except for vertebra and perirenal fat.and the VNC image.The VNC image which reduces radiation dosage derives from SDCT enhanced image might be used as a substitute for the TNC image.